WSR 18-07-098

PERMANENT RULES

DEPARTMENT OF

LABOR AND INDUSTRIES

[Filed March 20, 2018, 2:24 p.m., effective April 23, 2018]

Effective Date of Rule: April 23, 2018.

Purpose: This rule making is in response to the Occupational Safety and Health Administration's (OSHA) final rule for respirable crystalline silica in 29 C.F.R. 1926.1153 (Construction) and 29 C.F.R. 1910.1053 (General Industry/Maritime) which became effective on June 23, 2016. The department is required to update their rules to be at-least-as-effective-as OSHA.

The department's respirable crystalline silica rule covers construction and general industry in one rule (chapter 296-840 WAC), whereas OSHA has separate rules for each. The new silica chapter addresses and limits worker exposure to respirable crystalline silica in workplaces, with the intent of curbing lung cancer incidents, silicosis, chronic obstructive pulmonary disease and kidney disease in Washington workers. Furthermore, the following sections under WAC 296-841-20025 and 296-307-62625 were updated to reference the respirable crystalline silica rule.

The effective date of the rule is April 23, 2018, and the compliance dates are as follows:

•	For occupational exposures to respirable crystalline silica in construction work, employers must comply with all obligations of the rule by October 1, 2018.
•	For all occupational exposures to respirable crystalline silica other than construction work, employers must comply with all obligations of the rule by July 1, 2019, except:

º	Employers must comply with the medical surveillance requirements for employees exposed above the permissible exposure limit (PEL) for thirty or more days per year beginning on July 1, 2019.
º	Employers must comply with the medical surveillance requirements for employees exposed above the action level (AL) for thirty or more days per year beginning on June 23, 2020.
º	For hydraulic and fracturing operations in the oil and gas industry, employers must comply with the engineering control requirements beginning on July 1, 2022.

Amended Sections

WAC 296-841-20025 Permissible exposure limits (PELs) and 296-307-62625 Permissible exposure limits of air contaminants.

•	Updated PEL table to indicate that the tables apply only to exposures not covered by the new requirements in chapter 296-840 WAC

New Sections

WAC 296-840-095 Definitions.

•	Added definitions for the following: AL, competent person, construction work, director, DOSH, employee exposure, high-efficiency particulate air filter, objective data, PEL, physician or other licensed health care professional, regulated area, respirable crystalline silica, specialist.

WAC 296-840-100 Scope and application.

•	Added this section to explain that this chapter covers occupational exposures to respirable crystalline silica.
•	This section also provides exemptions to this proposed rule.

WAC 296-840-105 Exposure assessment.

•	Added this section to address the following areas that relate to occupational exposures to respirable crystalline silica:

-	PEL.
-	Exposure assessment.
-	Reassessment of exposures.
-	Methods of sample analysis.
-	Employee notification of assessment results.
-	Observation of monitoring.

WAC 296-840-110 Specified exposure control methods.

•	Added this section relating to construction work and other occupational exposures where the task performed is indistinguishable from a construction task identified in Table 1 of this proposed rule.
•	Added language to this section relating to implementing control measures.
•	Added language to this section relating to when respiratory protection is required.
•	Added Table 1 to this section relating to specified exposure control methods when working with materials containing crystalline silica.

WAC 296-840-115 Regulated areas.

•	Added this section for general industry/maritime, required to be established in areas where exposures exceed PEL and to limit access to the area.

WAC 296-840-120 Methods of compliance.

•	Added methods of compliance where tasks listed in Table 1 do not apply, including engineering and work practice controls, as well as abrasive blasting.

WAC 296-840-125 Respiratory protection.

•	Added this section that highlights requirements for respiratory protection.

WAC 296-840-130 Respiratory protection program.

•	Added respiratory protection program in accordance with chapter 296-842 WAC, Respirators.
•	Added respirator use in accordance with Table 1.

WAC 296-840-135 Housekeeping.

•	Added this section that addresses how a contaminated space can be cleaned.

WAC 296-840-140 Written exposure control plan.

•	Added requirements that apply to both general industry/maritime and construction industries.
•	Added a written plan with a description of tasks that involve exposure to silica, engineering control work practices and respiratory protection.
•	Added language that indicates employers should have [a] written plan available to each employee.
•	Added language for construction that requires procedures used to restrict access to work areas.
•	Added requirement language relating to a competent person.

WAC 296-840-145 Medical surveillance.

•	Added this section that requires medical surveillance to be available. Medical surveillance includes an initial examination, periodic examinations, and where needed examinations by a specialist.
•	Added tuberculosis form to help ensure tuberculosis assessment is thorough.

WAC 296-840-150 Communication of respirable crystalline silica hazards to employees.

•	Added this section that requires employers to comply with chapter 296-901 WAC, Globally harmonized system for hazard communication.
•	Added language that specifies what to include in posted signs.
•	Added language indicating that employees must understand health hazards associated with silica, tasks that could result in exposure, and measures to protect workers from exposure.

WAC 296-840-155 Recordkeeping.

•	Added this section indicating employers must maintain records of exposure and objective data that describes employee exposure, and medical surveillance methods.

WAC 296-840-160 Effective dates.

•	Added language indicating when this proposed rule becomes effective for construction and general/maritime industry.

WAC 296-840-165 Appendix A—Methods of sample analysis—Mandatory.

•	Added this section that explains the process employers are required to use when analyzing air samples and quality control procedures for respirable crystalline silica.

Citation of Rules Affected by this Order: New WAC 296-840-095, 296-840-100, 296-840-105, 296-840-110, 296-840-115, 296-840-120, 296-840-125, 296-840-130, 296-840-135, 296-840-140, 296-840-145, 296-840-150, 296-840-155, 296-840-160 and 296-840-165; and amending WAC 296-841-20025 and 296-307-62625.

Statutory Authority for Adoption: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060.

Other Authority: Chapter 49.17 RCW.

Adopted under notice filed as WSR 17-22-111 on October 31, 2017.

Changes Other than Editing from Proposed to Adopted Version:

•	WAC 296-841-20025, deleted changes to the permissible exposure limits and short-term exposure limit (STEL) related to beryllium. Changes related to beryllium are being addressed in a separate rule making specific to beryllium.
•	WAC 296-307-62625, deleted changes to the permissible exposure limits and STEL related to beryllium. Changes related to beryllium are being addressed in a separate rule making specific to beryllium.
•	WAC 296-840-095, omitted language regarding the application of the existing silica STELs under WAC 296-841-20025 and 296-307-62625 to exposures covered by the new rule under chapter 296-840 WAC.
•	WAC 296-840-100, omitted language regarding the application of the existing silica STELs under WAC 296-841-20025 and 296-307-62625 to exposures covered by the new rule under chapter 296-840 WAC.
•	WAC 296-840-105, omitted language regarding the application of the existing silica STELs under WAC 296-841-20025 and 296-307-62625 to exposures covered by the new rule under chapter 296-840 WAC.
•	WAC 296-840-145, added the wording "except for subsection (3)(e) of this section" to subsection (4) to be consistent with OSHA's language.
•	WAC 296-840-145, omitted language regarding the application of the existing silica STELs under WAC 296-841-20025 and 296-307-62625 to exposures covered by the new rule under chapter 296-840 WAC.
•	WAC 296-840-160, omitted language regarding the application of the existing silica STELs under WAC 296-841-20025 and 296-307-62625 to exposures covered by the new rule under chapter 296-840 WAC.
•	WAC 296-840-165, added the word "mandatory" to title of Appendix A.

Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 15, Amended 2, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.

Number of Sections Adopted at the Request of a Nongovernmental Entity: New 0, Amended 0, Repealed 0.

Number of Sections Adopted on the Agency's own Initiative: New 0, Amended 0, Repealed 0.

Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 15, Amended 2, Repealed 0.

Number of Sections Adopted using Negotiated Rule Making: New 0, Amended 0, Repealed 0; Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.

Date Adopted: March 20, 2018.

Joel Sacks

Director

AMENDATORY SECTION (Amending WSR 06-08-087, filed 4/4/06, effective 9/1/06)

WAC 296-307-62625 Permissible exposure limits of air contaminants.

IMPORTANT:

The following information applies to Table 3, Permissible Exposure Limits for Air Contaminants.

• Exposure needs to be determined from personal air samples taken in the breathing zone or from monitoring representative of the employee's breathing zone.

• Ppm refers to parts of vapor or gas per million parts of air by volume, at 25 degrees C and 760 mm Hg pressure.

• Mg/m3 refers to milligrams of substance per cubic meter of air.

• For a metal that is measured as the metal itself, only the CAS number for the metal is given. The CAS numbers for individual compounds of the metal are not provided. For more information about CAS registry numbers see the web site: http://www.cas.org.

• Time weighted averages (TWA8) represent the maximum allowed average exposure for any 8-hour time period. For work periods longer than 8 hours the TWA8 needs to be determined using the 8 continuous hours with the highest average concentration.

• Short-term exposure limits (STEL) represent maximum allowed average exposure for any fifteen-minute period, unless another time period is noted in Table 3.

• The ceiling represents the maximum allowed exposure for the shortest time period that can feasibly be measured.

• An "X" in the "skin" column indicates the substance can be absorbed through the skin, either by airborne or direct contact.

• Requirements for the use of gloves, coveralls, goggles, and other personal protective equipment can be found in WAC 296-307-100.

• The respirable fraction of particulate is measured by sampling with a size-selector having the following characteristics:


Mean aerodynamic diameter in micrometers	Percent passing the selector
1	97
2	91
3	74
4	50
5	30
6	17
7	9
8	5
10	1

Table 3 "Permissible Exposure Limits for Air Contaminants"


Substance	CAS	TWA8	STEL	Ceiling	Skin
Abate (Temephos)	3383-96-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Acetaldehyde	75-07-0	100 ppm	150 ppm	——	——
Acetic acid	64-19-7	10 ppm	20 ppm	——	——
Acetic anhydride	108-24-7	——	——	5 ppm	——
Acetone	67-64-1	750 ppm	1,000 ppm	——	——
Acetonitrile	75-05-8	40 ppm	60 ppm	——	——
2-Acetylaminofluorene	53-96-3	——	——	——	——
Acetylene	74-86-2	Simple asphyxiant	——	——	——
Acetylene dichloride (1,2-Dichloroethylene)	540-59-0	200 ppm	250 ppm	——	——
Acetylene tetrabromide	79-27-6	1 ppm	3 ppm	——	——
Acetylsalicylic acid (Aspirin)	50-78-2	5 mg/m3	10 mg/m3	——	——
Acrolein	107-02-8	0.1 ppm	0.3 ppm	——	——
Acrylamide	79-06-1	0.03 mg/m3	0.09 mg/m3	——	X
Acrylic acid	79-10-7	10 ppm	20 ppm	——	X
Acrylonitrile (Vinyl cyanide)	107-13-1	2 ppm	10 ppm	——	——
Aldrin	309-00-2	0.25 mg/m3	0.75 mg/m3	——	X
Allyl alcohol	107-18-6	2 ppm	4 ppm	——	X
Allyl chloride	107-05-1	1 ppm	2 ppm	——	——
Allyl glycidyl ether (AGE)	106-92-3	5 ppm	10 ppm	——	——
Allyl propyl disulfide	2179-59-1	2 ppm	3 ppm	——	——
alpha-Alumina (Aluminum oxide)	1344-28-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Aluminum (as Al)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pyro powders	——	5 mg/m3	10 mg/m3	——	——
Welding fumes	——	5 mg/m3	10 mg/m3	——	——
Soluble salts	——	2 mg/m3	4 mg/m3	——	——
Alkyls (NOC)	——	2 mg/m3	4 mg/m3	——	——
Aluminum oxide (Alundum, Corundum)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
4-Aminodiphenyl	92-67-1	——	——	——	——
2-Aminoethanol (Ethanolamine)	141-43-5	3 ppm	6 ppm	——	——
2-Aminopyridine	504-29-0	0.5 ppm	1.5 ppm	——	——
Amitrole	61-82-5	0.2 mg/m3	0.6 mg/m3	——	——
Ammonia	7664-41-7	25 ppm	35 ppm	——	——
Ammonium chloride, fume	12125-02-9	10 mg/m3	20 mg/m3	——	——
Ammonium sulfamate (Ammate)	7773-06-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5.0 mg/m3	10 mg/m3	——	——
n-Amyl acetate	628-63-7	100 ppm	150 ppm	——	——
sec-Amyl acetate	626-38-0	125 ppm	156 ppm	——	——
Aniline and homologues	62-53-3	2 ppm	4 ppm	——	X
Anisidine (o, p-isomers)	29191-52-4	0.1 ppm	0.3 ppm	——	X
Antimony and compounds (as Sb)	7440-36-0	0.5 mg/m3	1.5 mg/m3	——	——
ANTU (alpha Naphthyl thiourea)	86-88-4	0.3 mg/m3	0.9 mg/m3	——	——
Argon	7440-37-1	Simple asphyxiant	——	——	——
Arsenic, organic compounds (as As)	7440-38-2	0.2 mg/m3	0.6 mg/m3	——	——
Arsenic, inorganic compounds (as As) (when use is covered by WAC 296-62-07347)	7440-38-2	0.01 mg/m3	——	——	——
Arsenic, inorganic compounds (as As) (when use is not covered by WAC 296-62-07347)	7440-38-2	0.2 mg/m3	0.6 mg/m3	——	——
Arsine	7784-42-1	0.05 ppm	0.15 ppm	——	——
Asbestos	——	——	——	——	——
Asphalt (Petroleum fumes)	8052-42-4	5 mg/m3	10 mg/m3	——	——
Atrazine	1912-24-9	5 mg/m3	10 mg/m3	——	——
Azinphos methyl (Guthion)	86-50-0	0.2 mg/m3	0.6 mg/m3	——	X
Azodrin (Monocrotophos)	6923-22-4	0.25 mg/m3	0.75 mg/m3	——	——
Barium, soluble compounds (as Ba)	7440-39-3	0.5 mg/m3	1.5 mg/m3	——	——
Barium sulfate	7727-43-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Baygon (Propoxur)	114-26-1	0.5 mg/m3	1.5 mg/m3	——	——
Benomyl	17804-35-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Benzene	71-43-2	1 ppm	5 ppm	——	——
Benzidine	92-87-5	——	——	——	——
p-Benzoquinone (Quinone)	106-51-4	0.1 ppm	0.3 ppm	——	——
Benzo(a) pyrene (Coal tar pitch volatiles)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Benzoyl peroxide	94-36-0	5 mg/m3	10 mg/m3	——	——
Benzyl chloride	100-44-7	1ppm	3 ppm	——	——
Beryllium and beryllium compounds (as Be)	7440-41-7	0.002 mg/m3	0.005 mg/m3 (30 min.)	0.025 mg/m3	——
Biphenyl (Diphenyl)	92-52-4	0.2 ppm	0.6 ppm	——	——
Bismuth telluride, undoped	1304-82-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Bismuth telluride, Se-doped	——	5 mg/m3	10 mg/m3	——	——
Borates, tetra, sodium salts	——	——	——	——	——
Anhydrous	1330-43-4	1 mg/m3	3 mg/m3	——	——
Decahydrate	1303-96-4	5 mg/m3	10 mg/m3	——	——
Pentahydrate	12179-04-3	1 mg/m3	3 mg/m3	——	——
Boron oxide	1303-86-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Boron tribromide	10294-33-4	——	——	1 ppm	——
Boron trifluoride	6737-07-2	——	——	1 ppm	——
Bromacil	314-40-9	1 ppm	3 ppm	——	——
Bromine	7726-95-6	0.1 ppm	0.3 ppm	——	——
Bromine pentafluoride	7789-30-2	0.1 ppm	0.3 ppm	——	——
Bromochloromethane (((Chlorobromomthane)) Chlorobromomethane)	74-97-5	200 ppm	250 ppm	——	——
Bromoform	15-25-2	0.5 ppm	1.5 ppm	——	X
Butadiene (1,3-butadiene)	106-99-0	1 ppm	5 ppm	——	——
Butane	106-97-8	800 ppm	1,000 ppm	——	——
Butanethiol (Butyl mercaptan)	109-79-5	0.5 ppm	1.5 ppm	——	——
2-Butanone (Methyl ethyl ketone)	78-93-3	200 ppm	300 ppm	——	——
2-Butoxy ethanol (Butyl cellosolve)	111-76-2	25 ppm	38 ppm	——	X
n-Butyl acetate	123-86-4	150 ppm	200 ppm	——	——
sec-Butyl acetate	105-46-4	200 ppm	250 ppm	——	——
tert-Butyl acetate	540-88-5	200 ppm	250 ppm	——	——
Butyl acrylate	141-32-2	10 ppm	20 ppm	——	——
n-Butyl alcohol	71-36-3	——	——	50 ppm	X
sec-Butyl alcohol	78-92-2	100 ppm	150 ppm	——	——
tert-Butyl alcohol	75-65-0	100 ppm	150 ppm	——	——
Butylamine	109-73-9	——	——	5 ppm	X
Butyl cellosolve (2-Butoxy ethanol)	111-76-2	25 ppm	38 ppm	——	——
tert-Butyl chromate (as CrOs)	1189-85-1	——	——	0.1 mg/m3	X
n-Butyl glycidyl ether (BGE)	2426-08-6	25 ppm	38 ppm	——	——
n-Butyl lactate	138-22-7	5 ppm	10 ppm	—-	——
Butyl mercaptan	109-79-5	0.5 ppm	1.5 ppm	——	——
o-sec-Butylphenol	89-72-5	5 ppm	10 ppm	——	X
p-tert-Butyl-toluene	98-51-1	10 ppm	20 ppm	——	——
Cadmium oxide fume (as Cd)	1306-19-0	0.005 mg/m3	——	——	——
Cadmium dust and salts (as Cd)	7440-43-9	0.005 mg/m3	——	——	——
Calcium arsenate	——	0.01 mg/m3	——	——	——
Calcium carbonate	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Calcium cyanamide	156-62-7	0.5 mg/m3	1.5 mg/m3	——	——
Calcium hydroxide	1305-62-0	5 mg/m3	10 mg/m3	——	——
Calcium oxide	1305-78-8	2 mg/m3	4 mg/m3	——	——
Calcium silicate	1344-95-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Calcium sulfate	7778-18-9	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Camphor (synthetic)	76-22-2	2 mg/m3	4 mg/m3	——	——
Caprolactam	105-60-2	——	——	——	——
Dust	——	1 mg/m3	3 mg/m3	——	——
Vapor	——	5 ppm	10 ppm	——	——
Captafol (Difolatan)	2425-06-1	0.1 mg/m3	0.3 mg/m3	——	X
Captan	133-06-2	5 mg/m3	10 mg/m3	——	——
Carbaryl (Sevin)	63-25-2	5 mg/m3	10 mg/m3	——	——
Carbofuran (Furadon)	1563-66-2	0.1 mg/m3	0.3 mg/m3	——	——
Carbon black	1333-86-4	3.5 mg/m3	7 mg/m3	——	——
Carbon dioxide	124-38-9	5,000 ppm	30,000 ppm	——	——
Carbon disulfide	75-15-0	4 ppm	12 ppm	——	X
Carbon monoxide	630-08-0	35 ppm	200 ppm (5 min.)	1,500 ppm	——
Carbon tetrabromide	558-13-4	0.1 ppm	0.3 ppm	——	——
Carbon tetrachloride (Tetrachloromethane)	56-23-5	2 ppm	4 ppm	——	X
Carbonyl chloride (Phosgene)	7803-51-2	0.1 ppm	0.3 ppm	——	——
Carbonyl fluoride	353-50-4	2 ppm	5 ppm	——	——
Catechol (Pyrocatechol)	120-80-9	5 ppm	10 ppm	——	X
Cellosolve acetate (2-Ethoxyethylacetate)	111-15-9	5 ppm	10 ppm	——	X
Cellulose (paper fiber)	9004-34-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Cesium hydroxide	21351-79-1	2 mg/m3	4 mg/m3	——	——
Chlordane	57-74-9	0.5 mg/m3	1.5 mg/m3	——	X
Chlorinated camphene (Toxaphen)	8001-35-2	0.5 mg/m3	1 mg/m3	——	X
Chlorinated diphenyl oxide	55720-99-5	0.5 mg/m3	1.5 mg/m3	——	——
Chlorine	7782-50-5	0.5 ppm	——	1 ppm	——
Chlorine dioxide	10049-04-4	0.1 ppm	0.3 ppm	——	——
Chlorine trifluoride	7790-91-2	——	——	0.1 ppm	——
Chloroacetaldehyde	107-20-0	——	——	1 ppm	——
a-Chloroacetophenone (Phenacyl chloride)	532-21-4	0.05 ppm	0.15 ppm	——	——
Chloroacetyl chloride	79-04-9	0.05 ppm	0.15 ppm	——	——
Chlorobenzene (Monochlorobenzene)	108-90-7	75 ppm	113 ppm	——	——
o-Chlorobenzylidene malononitrile (OCBM)	2698-41-1	——	——	0.05 ppm	X
Chlorobromomethane	74-97-5	200 ppm	250 ppm	——	——
2-Chloro-1, 3-butadiene (beta-Chloroprene)	126-99-8	10 ppm	20 ppm	——	X
Chlorodifluoromethane	75-45-6	1,000 ppm	1,250 ppm	——	——
Chlorodiphenyl (42% Chlorine) (PCB) (Polychlorobiphenyls)	53469-21-9	1 mg/m3	3 mg/m3	——	X
Chlorodiphenyl (54% Chlorine) (Polychlorobiphenyls (PCB))	11097-69-1	0.5 mg/m3	1.5 mg/m3	——	X
1-Chloro-2, 3-epoxypropane (Epichlorhydrin)	106-89-8	2 ppm	4 ppm	——	X
2-Chloroethanol (Ethylene chlorohydrin)	107-07-3	——	——	1 ppm	X
Chloroethylene (vinyl chloride)	75-01-4	1 ppm	5 ppm	——	——
Chloroform (Trichloromethane)	67-66-3	2 ppm	4 ppm	——	——
1-Chloro-1-nitropropane	600-25-9	2 ppm	4 ppm	——	——
bis-Chloromethyl ether	542-88-1	——	——	——	——
Chloromethyl methyl ether (Methyl chloromethyl ether)	107-30-2	——	——	——	——
Chloropentafluoroethane	76-15-3	1,000 ppm	1,250 ppm	——	——
Chloropicrin (Nitrotrichloromethane)	76-06-2	0.1 ppm	0.3 ppm	——	——
beta-Chloroprene (2-Chloro-1, 3-butadiene)	126-99-8	10 ppm	20 ppm	——	X
o-Chlorostyrene	2039-87-4	50 ppm	75 ppm	——	——
o-Chlorotoluene	95-49-8	50 ppm	75 ppm	——	——
2-Chloro-6-trichloromethyl pyridine (Nitrapyrin)	1929-82-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Chlorpyrifos	2921-88-2	0.2 mg/m3	0.6 mg/m3	——	X
Chromic acid and chromates (as CrO3)	Varies with compound	0.1 mg/m3	0.3 mg/m3	——	——
Chromium, soluble, chromic and chromous salts (as Cr)	7440-47-3	0.5 mg/m3	1.5 mg/m3	——	——
Chromium (VI) compounds (as Cr)	——	0.05 mg/m3	0.15 mg/m3	——	——
Chromium metal and insoluble salts	7440-47-3	0.5 mg/m3	1.5 mg/m3	——	——
Chromyl chloride	14977-61-8	0.025 ppm	0.075 ppm	——	——
Chrysene (Coal tar pitch volatiles)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Clopidol	2971-90-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Coal dust (less than 5% SiO2)	——	——	——	——	——
Respirable fraction	——	2 mg/m3	4 mg/m3	——	——
Coal dust (greater than or equal to 5% SiO2)	——	——	——	——	——
Respirable fraction	——	0.1 mg/m3	0.3 mg/m3	——	——
Coal tar pitch volatiles (benzene soluble fraction) (Particulate polycyclic aromatic hydrocarbons)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Cobalt, metal fume & dust (as Co)	7440-48-4	0.05 mg/m3	0.15 mg/m3	——	——
Cobalt carbonyl (as Co)	10210-68-1	0.1 mg/m3	0.3 mg/m3	——	——
Cobalt hydrocarbonyl (as Co)	16842-03-8	0.1 mg/m3	0.3 mg/m3	——	——
Coke oven emissions	——	0.15 mg/m3	——	——	——
Copper (as Cu)	7440-50-8	——	——	——	——
Fume	——	0.1 mg/m3	0.3 mg/m3	——	——
Dusts and mists	——	1 mg/m3	3 mg/m3	——	——
Cotton dust (raw) (waste sorting, blending, cleaning, willowing and garetting)	——	1 mg/m3	——	——	——
Corundum (Aluminum oxide)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Crag herbicide (Sesone, Sodium-2, 4-dichloro-phenoxyethyl sulfate)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Cresol (all isomers)	1319-77-3	5 ppm	10 ppm	——	X
Crotonaldehyde	123-73-9; 4170-30-3	2 ppm	4 ppm	——	——
Crufomate	299-86-5	5 mg/m3	10 mg/m3	——	——
Cumene	98-82-8	50 ppm	75 ppm	——	X
Cyanamide	420-04-2	2 mg/m3	4 mg/m3	——	——
Cyanide (as CN)	Varies with compound	5 mg/m3	10 mg/m3	——	X
Cyanogen	460-19-5	10 ppm	20 ppm	——	——
Cyanogen chloride	506-77-4	——	——	0.3 ppm	——
Cyclohexane	110-82-7	300 ppm	375 ppm	——	——
Cyclohexanol	108-93-0	50 ppm	75 ppm	——	X
Cyclohexanone	108-94-1	25 ppm	38 ppm	——	X
Cyclohexene	110-83-8	300 ppm	375 ppm	——	——
Cyclohexylamine	108-91-8	10 ppm	20 ppm	——	——
Cyclonite (RDX)	121-82-4	1.5 mg/m3	3.0 mg/m3	——	X
Cyclopentadiene	542-92-7	75 ppm	113 ppm	——	——
Cyclopentane	287-92-3	600 ppm	750 ppm	——	——
Cyhexatin (Tricyclohexyltin hydroxide)	13121-70-5	5 mg/m3	10 mg/m3	——	——
2,4-D (Dichlorophenoxy-acetic acid)	94-75-7	10 mg/m3	20 mg/m3	——	——
DBCP (1,2-Dibromo-3-chloropropane)	96-12-8	0.001 ppm	——	0.005 ppm	——
DDT (Dichlorodiphenyltri-chloroethane)	50-29-3	1 mg/m3	3 mg/m3	——	X
DDVP, (Dichlorvos)	62-73-7	0.1 ppm	0.3 ppm	——	X
Dasanit (Fensulfothion)	115-90-2	0.1 mg/m3	0.3 mg/m3	——	——
Decaborane	17702-41-9	0.05 ppm	0.15 ppm	——	X
Demeton	8065-48-3	0.01 ppm	0.03 ppm	——	X
Diacetone alcohol (4-hydroxy-4-methyl- 2-pentanone)	123-42-2	50 ppm	75 ppm	——	——
1, 2-Diaminoethane (Ethylenediamine)	107-15-3	10 ppm	20 ppm	——	——
Diazinon	333-41-5	0.1 mg/m3	0.3 mg/m3	——	X
Diazomethane	334-88-3	0.2 ppm	0.6 ppm	——	——
Diborane	19287-45-7	0.1 ppm	0.3 ppm	——	——
Dibrom (see Naled)	300-76-5	3 mg/m3	6 mg/m3	——	X
1, 2-Dibromo-3-chloropropane (DBCP)	96-12-8	0.001 ppm	——	0.005 ppm	——
2-N-Dibutylamino ethanol	102-81-8	2 ppm	4 ppm	——	X
Dibutyl phosphate	107-66-4	1 ppm	2 ppm	——	——
Dibutyl phthalate	84-74-2	5 mg/m3	10 mg/m3	——	——
Dichloroacetylene	7572-29-4	——	——-	0.1 ppm	——
o-Dichlorobenzene	95-50-1	——	——	50 ppm	——
p-Dichlorobenzene	106-46-7	75 ppm	110 ppm	——	——
3, 3'-Dichlorobenzidine	91-94-1	——	——	——	——
Dichlorodiphenyltri-chloroethane (DDT)	50-29-3	1 mg/m3	3 mg/m3	——	X
Dichlorodifluoromethane	75-71-8	1,000 ppm	1,250 ppm	——	——
1, 3-Dichloro-5, 5-dimethyl hydantoin	118-52-5	0.2 mg/m3	0.4 mg/m3	——	——
1, 1-Dichloroethane (Ethylidine chloride)	75-34-3	100 ppm	150 ppm	——	——
1, 2-Dichloroethane (Ethylene dichloride)	107-06-2	1 ppm	2 ppm	——	——
1, 1-Dichloroethylene (Vinylidene chloride)	75-35-4	1 ppm	3 ppm	——	——
1, 2-Dichloroethylene (Acetylene dichloride)	540-59-0	200 ppm	250 ppm	——	——
Dichloroethyl ether	111-44-4	5 ppm	10 ppm	——	X
Dichlorofluoromethane	75-43-4	10 ppm	20 ppm	——	——
Dichloromethane (Methylene chloride)	75-09-2	25 ppm	125 ppm	——	——
1, 1-Dichloro-1-nitroethane	594-72-9	2 ppm	10 ppm	——	——
Dichlorophenoxyacetic acid (2, 4-D)	94-75-7	10 mg/m3	20 mg/m3	——	——
1, 2-Dichloropropane (Propylene dichloride)	78-87-5	75 ppm	110 ppm	——	——
Dichloropropene	542-75-6	1 ppm	3 ppm	——	X
2, 2-Dichloropropionic acid	75-99-0	1 ppm	3 ppm	——	——
Dichlorotetrafluoroethane	76-14-2	1,000 ppm	1,250 ppm	——	——
Dichlorvos (DDVP)	62-73-7	0.1 ppm	0.3 ppm	——	X
Dicrotophos	141-66-2	0.25 mg/m3	0.75 mg/m3	——	X
Dicyclopentadiene	77-73-6	5 ppm	10 ppm	——	——
Dicyclopentadienyl iron	102-54-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Dieldrin	60-57-1	0.25 mg/m3	0.75 mg/m3	——	X
Diethanolamine	111-42-2	3 ppm	6 ppm	——	——
Diethylamine	109-89-7	10 ppm	25 ppm	——	——
2-Diethylaminoethanol	100-37-8	10 ppm	20 ppm	——	X
Diethylene triamine	111-40-0	1 ppm	3 ppm	——	X
Diethyl ether (Ethyl ether)	60-29-7	400 ppm	500 ppm	——	——
Diethyl ketone	96-22-0	200 ppm	250 ppm	——	——
Diethyl phthalate	84-66-2	5 mg/m3	10 mg/m3	——	——
Difluorodibromomethane	75-61-6	100 ppm	150 ppm	——	——
Difolatan (Captafol)	2425-06-1	0.1 mg/m3	0.3 mg/m3	——	X
Diglycidyl ether (DGE)	2238-07-5	0.1 ppm	0.3 ppm	——	——
Dihydroxybenzene (Hydroquinone)	123-31-9	2 mg/m3	4 mg/m3	——	——
Diisobutyl ketone (2, 6- Dimethylheptanone)	108-83-8	25 ppm	38 ppm	——	——
Diisopropylamine	108-18-9	5 ppm	10 ppm	——	X
Dimethoxymethane (Methylal)	109-87-5	1,000 ppm	1,250 ppm	——	——
Dimethyl acetamide	127-19-5	10 ppm	20 ppm	——	X
Dimethylamine	124-40-3	10 ppm	20 ppm	——	——
4-Dimethylaminoazo benzene	60-11-7	——	——	——	——
Dimethylaminobenzene (Xylidene)	1300-73-8	2 ppm	4 ppm	——	X
Dimethylaniline (N, N-Dimethylaniline)	121-69-7	5 ppm	10 ppm	——	X
Dimethylbenzene (Xylene)	1300-73-8	100 ppm	150 ppm	——	——
Dimethyl-1, 2-dibromo-2, 2-dichloroethyl phosphate (Naled)	300-76-5	3 mg/m3	6 mg/m3	——	X
Dimethylformamide	68-12-2	10 ppm	20 ppm	——	X
2, 6-Dimethylheptanone (Diisobutyl ketone)	108-83-8	25 ppm	38 ppm	——	——
1, 1-Dimethylhydrazine	57-14-7	0.5 ppm	1.5 ppm	——	X
Dimethyl phthalate	131-11-3	5 mg/m3	10 mg/m3	——	——
Dimethyl sulfate	77-78-1	0.1 ppm	0.3 ppm	——	X
Dinitolmide (3, 5-Dinitro-o-toluamide)	148-01-6	5 mg/m3	10 mg/m3	——	——
Dinitrobenzene (all isomers - alpha, meta and para)	528-29-0; 99-65-0; 100-25-4	0.15 ppm	0.45 ppm	——	X
Dinitro-o-cresol	534-52-1	0.2 mg/m3	0.6 mg/m3	——	X
3, 5-Dinitro-o-toluamide (Dinitolmide)	148-01-6	5 mg/m3	10 mg/m3	——	——
Dinitrotoluene	25321-14-6	1.5 mg/m3	3 mg/m3	——	X
Dioxane (Diethylene dioxide)	123-91-1	25 ppm	38 ppm	——	X
Dioxathion	78-34-2	0.2 mg/m3	0.6 mg/m3	——	X
Diphenyl (Biphenyl)	92-52-4	0.2 ppm	0.6 ppm	——	——
Diphenylamine	122-39-4	10 mg/m3	20 mg/m3	——	——
Diphenylmethane diisocyanate (Methylene bisphenyl isocyanate (MDI))	101-68-8	——	——	0.02 ppm	——
Dipropylene glycol methyl ether	34590-94-8	100 ppm	150 ppm	——	X
Dipropyl ketone	123-19-3	50 ppm	75 ppm	——	——
Diquat	85-00-7	0.5 mg/m3	1.5 mg/m3	——	——
Di-sec, Octyl phthalate (Di-2-ethylhexylphthalate)	117-81-7	5 mg/m3	10 mg/m3	——	——
Disulfram	97-77-8	2 mg/m3	4 mg/m3	——	——
Disulfoton	298-04-4	0.1 mg/m3	0.3 mg/m3	——	X
2, 6-Di-tert-butyl-p-cresol	128-37-0	10 mg/m3	20 mg/m3	——	——
Diuron	330-54-1	10 mg/m3	20 mg/m3	——	——
Divinyl benzene	1321-74-0	10 ppm	20 ppm	——	——
Emery	12415-34-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Endosulfan (Thiodan)	115-29-7	0.1 mg/m3	0.3 mg/m3	——	X
Endrin	72-20-8	0.1 mg/m3	0.3 mg/m3	——	X
Epichlorhydrin (1-Chloro-2, 3-epoxypropane)	106-89-8	2 ppm	4 ppm	——	X
EPN	2104-64-5	0.5 mg/m3	1.5 mg/m3	——	X
1, 2-Epoxypropane (Propylene oxide)	75-56-9	20 ppm	30 ppm	——	——
2, 3-Epoxy-1-propanol (Glycidol)	556-52-5	25 ppm	38 ppm	——	——
Ethane	——	Simple asphyxiant	——	——	——
Ethanethiol (Ethyl mercaptan)	75-08-1	0.5 ppm	1.5 ppm	——	——
Ethanol (Ethyl alcohol)	64-17-5	1,000 ppm	1,250 ppm	——	——
Ethanolamine (2-Aminoethanol)	141-43-5	3 ppm	6 ppm	——	——
Ethion	563-12-2	0.4 mg/m3	1.2 mg/m3	——	X
2-Ethoxyethanol (Glycol monoethyl ether)	110-80-5	5 ppm	10 ppm	——	X
2-Ethoxyethyl acetate (Cellosolve acetate)	111-15-9	5 ppm	10 ppm	——	X
Ethyl acetate	141-78-6	400 ppm	500 ppm	——	——
Ethyl acrylate	140-88-5	5 ppm	25 ppm	——	X
Ethyl alcohol (ethanol)	64-17-5	1,000 ppm	1,250 ppm	——	——
Ethylamine	75-04-07	10 ppm	20 ppm	——	——
Ethyl amyl ketone (5-Methyl-3-hepatone)	541-85-5	25 ppm	38 ppm	——	——
Ethyl benzene	100-41-4	100 ppm	125 ppm	——	——
Ethyl bromide	74-96-4	200 ppm	250 ppm	——	——
Ethyl butyl ketone (3-Heptanone)	106-35-4	50 ppm	75 ppm	——	——
Ethyl chloride	75-00-3	1,000 ppm	1,250 ppm	——	——
Ethylene	74-85-1	Simple asphyxiant	——	——	——
Ethylene chlorohydrin (2-Chloroethanol)	107-07-3	——	——	1 ppm	X
Ethylenediamine (1,2-Diaminoethane)	107-15-3	10 ppm	20 ppm	——	X
Ethylene dibromide	106-93-4	0.1 ppm	0.5 ppm	——	——
Ethylene dichloride (1,2-Dichloroethane)	107-06-2	1 ppm	2 ppm	——	——
Ethylene glycol	107-21-1	——	——	50 ppm	——
Ethylene glycol dinitrate	628-96-6	——	0.1 mg/m3	——	X
Ethylene glycol monomethyl ether acetate (Methyl cellosolve acetate)	——	5 ppm	10 ppm	——	X
Ethyleneimine	151-56-4	——	——	——	X
Ethylene oxide	75-21-8	1 ppm	5 ppm	——	——
Ethyl ether (Diethyl ether)	60-29-7	400 ppm	500 ppm	——	——
Ethyl formate	109-94-4	100 ppm	125 ppm	——	——
Ethylidine chloride (1, 1-Dichloroethane)	107-06-2	1 ppm	2 ppm	——	——
Ethylidene norbornene	16219-75-3	——	——	5.0 ppm	——
Ethyl mercaptan (Ethanethiol)	75-08-1	0.5 ppm	1.5 ppm	——	——
n-Ethylmorpholine	100-74-3	5 ppm	10 ppm	——	X
Ethyl sec-amyl ketone (5-methyl-3-heptanone)	541-85-5	25 ppm	38 ppm	——	——
Ethyl silicate	78-10-4	10 ppm	20 ppm	——	——
Fenamiphos	22224-92-6	0.1 mg/m3	0.3 mg/m3	——	X
Fensulfothion (Dasanit)	115-90-2	0.1 mg/m3	0.3 mg/m3	——	——
Fenthion	55-38-9	0.2 mg/m3	0.6 mg/m3	——	X
Ferbam	——	——	——	——	——
Total particulate	14484-64-1	10 mg/m3	20 mg/m3	——	——
Ferrovanadium dust	12604-58-9	1 mg/m3	3 mg/m3	——	——
Fluorides (as F)	Varies with compound	2.5 mg/m3	5 mg/m3	——	——
Fluorine	7782-41-4	0.1 ppm	0.3 ppm	——	——
Fluorotrichloromethane (see Trichlorofluoro methane)	75-69-4	——	——	1,000 ppm	——
Fonofos	944-22-9	0.1 mg/m3	0.3 mg/m3	——	X
Formaldehyde	50-00-0	0.75 ppm	2 ppm	——	——
Formamide	75-12-7	20 ppm	30 ppm	——	——
Formic acid	64-18-6	5 ppm	10 ppm	——	——
Furadon (carbofuran)	1563-66-2	0.1 mg/m3	0.3 mg/m3	——	——
Furfural	98-01-1	2 ppm	4 ppm	——	X
Furfuryl alcohol	98-00-0	10 ppm	15 ppm	——	X
Gasoline	8006-61-9	300 ppm	500 ppm	——	——
Germanium tetrahydride	7782-65-2	0.2 ppm	0.6 ppm	——	——
Glass, fibrous or dust	——	10 mg/m3	20 mg/m3	——	——
Gluteraldehyde	111-30-8	——	——	0.2 ppm	——
Glycerin mist	56-81-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Glycidol (2, 3-Epoxy-1-propanol)	556-52-5	25 ppm	38 ppm	——	——
Glycol monoethyl ether (2-Ethoxyethanol)	110-80-5	5 ppm	10 ppm	——	X
Grain dust (oat, wheat, barley)	——	10 mg/m3	20 mg/m3	——	——
Graphite, natural	7782-42-5	——	——	——	——
Respirable particulate	——	2.5 mg/m3	5 mg/m3	——	——
Graphite, synthetic	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Guthion (Azinphosmethyl)	86-50-0	0.2 mg/m3	0.6 mg/m3	——	X
Gypsum	13397-24-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Hafnium	7440-58-6	0.5 mg/m3	1.5 mg/m3	——	——
Helium	——	Simple asphyxiant	——	——	——
Heptachlor	76-44-8	0.5 mg/m3	1.5 mg/m3	——	X
Heptane (n-heptane)	142-82-5	400 ppm	500 ppm	——	——
2-Heptanone (Methyl n-amyl ketone)	110-43-0	50 ppm	75 ppm	——	——
3-Heptanone (Ethyl butyl ketone)	106-35-4	50 ppm	75 ppm	——	——
Hexachlorobutadiene	87-68-3	0.02 ppm	0.06 ppm	——	X
Hexachlorocyclopentadiene	77-47-4	0.01 ppm	0.03 ppm	——	——
Hexachloroethane	67-72-1	1 ppm	3 ppm	——	X
Hexachloronaphthalene	1335-87-1	0.2 mg/m3	0.6 mg/m3	——	X
Hexafluoroacetone	684-16-2	0.1 ppm	0.3 ppm	——	X
Hexane	——	——	——	——	——
n-hexane	110-54-3	50 ppm	75 ppm	——	——
other isomers	Varies with compound	500 ppm	1,000 ppm	——	——
2-Hexanone (Methyl-n-butyl ketone)	591-78-6	5 ppm	10 ppm	——	——
Hexone (Methyl isobutyl ketone)	108-10-1	50 ppm	75 ppm	——	——
sec-Hexyl acetate	108-84-9	50 ppm	75 ppm	——	——
Hexylene glycol	107-41-5	——	——	25 ppm	——
Hydrazine	302-01-2	0.1 ppm	0.3 ppm	——	X
Hydrogen	——	Simple asphyxiant	——	——	——
Hydrogenated terphenyls	61788-32-7	0.5 ppm	1.5 ppm	——	——
Hydrogen bromide	10035-10-6	——	——	3.0 ppm	——
Hydrogen chloride	7647-01-0	——	——	5.0 ppm	——
Hydrogen cyanide	74-90-8	——	4.7 ppm	——	X
Hydrogen fluoride	7664-39-3	——	——	3 ppm	——
Hydrogen peroxide	7722-84-1	1 ppm	3 ppm	——	——
Hydrogen selenide (as Se)	7783-07-5	0.05 ppm	0.15 ppm	——	——
Hydrogen sulfide	7783-06-4	10 ppm	15 ppm	——	——
Hydroquinone (Dihydroxybenzene)	123-31-9	2 mg/m3	4 mg/m3	——	——
4-Hydroxy-4-methyl-2-pentanone (Diacetone alcohol)	123-42-2	50 ppm	75 ppm	——	——
2-Hydroxypropyl acrylate	99-61-1	0.5 ppm	1.5 ppm	——	X
Indene	95-13-6	10 ppm	20 ppm	——	——
Indium and compounds (as In)	7440-74-6	0.1 mg/m3	0.3 mg/m3	——	——
Iodine	7553-56-2	——	——	0.1 ppm	——
Iodoform	75-47-8	0.6 ppm	1.8 ppm	——	——
Iron oxide dust and fume (as Fe)	1309-37-1	——	——	——	——
Total particulate	——	5 mg/m3	10 mg/m3	——	——
Iron pentacarbonyl (as Fe)	13463-40-6	0.1 ppm	0.2 ppm	——	——
Iron salts, soluble (as Fe)	Varies with compound	1 mg/m3	3 mg/m3	——	——
Isoamyl acetate	123-92-2	100 ppm	150 ppm	——	——
Isoamyl alcohol (primary and secondary)	123-51-3	100 ppm	125 ppm	——	——
Isobutyl acetate	110-19-0	150 ppm	188 ppm	——	——
Isobutyl alcohol	78-83-1	50 ppm	75 ppm	——	——
Isooctyl alcohol	26952-21-6	50 ppm	75 ppm	——	X
Isophorone	78-59-1	4 ppm	——	5 ppm	——
Isophorone diisocyanate	4098-71-9	0.005 ppm	0.02 ppm	——	X
Isopropoxyethanol	109-59-1	25 ppm	38 ppm	——	——
Isopropyl acetate	108-21-4	250 ppm	310 ppm	——	——
Isopropyl alcohol	67-63-0	400 ppm	500 ppm	——	——
Isopropylamine	75-31-0	5 ppm	10 ppm	——	——
N-Isopropylaniline	768-52-5	2 ppm	4 ppm	——	X
Isopropyl ether	108-20-3	250 ppm	313 ppm	——	——
Isopropyl glycidyl ether (IGE)	4016-14-2	50 ppm	75 ppm	——-	——
Kaolin	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Ketene	463-51-4	0.5 mg/m3	1.5 mg/m3	——	——
Lannate (Methomyl)	16752-77-5	2.5 mg/m3	5 mg/m3	——	——
Lead, inorganic (as Pb)	7439-92-1	0.05 mg/m3	——	——	——
Lead arsenate (as Pb)	3687-31-8	0.05 mg/m3	——	——	——
Lead chromate (as Pb)	7758-97-6	0.05 mg/m3	——	——	——
Limestone	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Lindane	58-89-9	0.5 mg/m3	1.5 mg/m3	——	X
Lithium hydride	7580-67-8	0.025 mg/m3	0.075 mg/m3	——	——
L.P.G. (liquified petroleum gas)	68476-85-7	1,000 ppm	1,250 ppm	——	——
Magnesite	546-93-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Magnesium oxide fume	1309-48-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Malathion	121-75-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	X
Maleic anhydride	108-31-6	0.25 ppm	0.75 ppm	——	——
Manganese and compounds (as Mn)	7439-96-5	——	——	5 mg/m3	——
Manganese cyclopentadienyl tricarbonyl (as Mn)	12079-65-1	0.1 mg/m3	0.3 mg/m3	——	X
Manganese tetroxide and fume (as Mn)	7439-96-5	1 mg/m3	3 mg/m3	——	——
Marble	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
MBOCA (4, 4'-Methylene bis (2-chloro-aniline))	101-14-4	——	——	——	X
MDA (4, 4-Methylene dianiline)	101-77-9	0.01 ppm	0.1 ppm	——	X
MDI (Methylene bisphenyl isocyanate) (Diphenylmethane diisocyanate)	101-68-8	——	——	0.02 ppm	——
MEK (Methyl ethyl ketone) (2-Butanone)	78-93-3	200 ppm	300 ppm	——	——
MEKP (Methyl ethyl ketone peroxide)	1338-23-4	——	——	0.2 ppm	——
Mercury (as Hg)	7439-97-6	——	——	——	——
Aryl and inorganic	——	0.1 mg/m3	0.3 mg/m3	——	X
Organo-alkyl compounds	——	0.01 mg/m3	0.03 mg/m3	——	X
Vapor	——	0.05 mg/m3	0.15 mg/m3	——	X
Mesityl oxide	141-79-7	15 ppm	25 ppm	——	——
Methacrylic acid	79-41-4	20 ppm	30 ppm	——	X
Methane	——	Simple asphyxiant	——	——	——
Methanethiol (Methyl mercaptan)	74-93-1	0.5 ppm	1.5 ppm	——	——
Methanol (Methyl alcohol)	67-56-1	200 ppm	250 ppm	——	X
Methomyl (lannate)	16752-77-5	2.5 mg/m3	5 mg/m3	——	——
Methoxychlor	72-43-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
2-Methoxyethanol (Methyl cellosolve)	109-86-4	5 ppm	10 ppm	——	X
2-Methoxyethyl acetate (Methyl cellosolve acetate)	110-49-6	5 ppm	10 ppm	——	X
4-Methoxyphenol	150-76-5	5 mg/m3	10 mg/m3	——	——
Methyl acetate	79-20-9	200 ppm	250 ppm	——	——
Methyl acetylene (propyne)	74-99-7	1,000 ppm	1,250 ppm	——	——
Methyl acetylene-propadiene mixture (MAPP)	——	1,000 ppm	1,250 ppm	——	——
Methyl acrylate	96-33-3	10 ppm	20 ppm	——	X
Methylacrylonitrile	126-98-7	1 ppm	3 ppm	——	X
Methylal (Dimethoxy-methane)	109-87-5	1,000 ppm	1,250 ppm	——	——
Methyl alcohol (methanol)	67-56-1	200 ppm	250 ppm	——	X
Methylamine	74-89-5	10 ppm	20 ppm	——	——
Methyl amyl alcohol (Methyl isobutyl carbinol)	108-11-2	25 ppm	40 ppm	——	X
Methyl n-amyl ketone (2-Heptanone)	110-43-0	50 ppm	75 ppm	——	——
N-Methyl aniline (Monomethyl aniline)	100-61-8	0.5 ppm	1.5 ppm	——	X
Methyl bromide	74-83-9	5 ppm	10 ppm	——	X
Methyl-n-butyl ketone (2-Hexanone)	591-78-6	5 ppm	10 ppm	——	——
Methyl cellosolve (2-Methoxyethanol)	109-86-4	5 ppm	10 ppm	——	X
Methyl cellosolve acetate (2-Methoxyethyl acetate)	110-49-6	5 ppm	10 ppm	——	X
Methyl chloride	74-87-3	50 ppm	100 ppm	——	——
Methyl chloroform (1, 1, 1-trichlorethane)	71-55-6	350 ppm	450 ppm	——	——
Methyl chloromethyl ether (chloromethyl methyl ether)	107-30-2	——	——	——	——
Methyl 2-cyanoacrylate	137-05-3	2 ppm	4 ppm	——	——
Methylcyclohexane	108-87-2	400 ppm	500 ppm	——	——
Methylcyclohexanol	25639-42-3	50 ppm	75 ppm	——	——
Methylcyclohexanone	583-60-8	50 ppm	75 ppm	——	X
Methylcyclopentadienyl manganese tricarbonyl (as Mn)	12108-13-3	0.2 mg/m3	0.6 mg/m3	——	X
Methyl demeton	8022-00-2	0.5 mg/m3	1.5 mg/m3	——	X
Methylene bisphenyl isocyanate (MDI) (Diphenylmethane diisocyanate)	101-68-8	——	——	0.02 ppm	——
4, 4'-Methylene bis (2-chloro-aniline) (MBOCA)	101-14-4	——	——	——	X
Methylene bis (4-cyclohexylisocyanate)	5124-30-1	——	——	0.01 ppm	——
Methylene chloride (Dichloromethane)	75-09-2	25 ppm	125 ppm	——	——
4, 4-Methylene dianiline (MDA)	101-77-9	0.01 ppm	0.1 ppm	——	X
Methyl ethyl ketone (MEK) (2-Butanone)	78-93-3	200 ppm	300 ppm	——	——
Methyl ethyl ketone peroxide (MEKP)	1338-23-4	——	——	0.2 ppm	——
Methyl formate	107-31-3	100 ppm	150 ppm	——	——
5-Methyl-3-heptanone (Ethyl amyl ketone)	541-85-5	25 ppm	38 ppm	——	——
Methyl hydrazine (Monomethyl hydrazine)	60-34-4	——	——	0.2 ppm	X
Methyl iodide	74-88-4	2 ppm	4 ppm	——	X
Methyl isoamyl ketone	110-12-3	50 ppm	75 ppm	——	——
Methyl isobutyl carbinol (Methyl amyl alcohol)	108-11-2	25 ppm	40 ppm	——	X
Methyl isobutyl ketone (Hexone)	108-10-1	50 ppm	75 ppm	——	——
Methyl isocyanate	624-83-9	0.02 ppm	0.06 ppm	——	X
Methyl isopropyl ketone	563-80-4	200 ppm	250 ppm	——	——
Methyl mercaptan (Methanethiol)	74-93-1	0.5 ppm	1.5 ppm	——	——
Methyl methacrylate	80-62-6	100 ppm	150 ppm	——	——
Methyl parathion	298-00-0	0.2 mg/m3	0.6 mg/m3	——	X
Methyl propyl ketone (2-Pentanone)	107-87-9	200 ppm	250 ppm	——	——
Methyl silicate	684-84-5	1 ppm	3 ppm	——	——
alpha-Methyl styrene	98-83-9	50 ppm	100 ppm	——	——
Mevinphos (Phosdrin)	7786-34-7	0.01 ppm	0.03 ppm	——	X
Metribuzin	21087-64-9	5 mg/m3	10 mg/m3	——	——
Mica (Silicates) Respirable fraction	12001-26-2	3 mg/m3	6 mg/m3	——	——
Molybdenum (as Mo)	7439-98-7	——	——	——	——
Soluble compounds	——	5 mg/m3	10 mg/m3	——	——
Insoluble compounds	——	10 mg/m3	20 mg/m3	——	——
Monochlorobenzene (Chlorobenzene)	108-90-7	75 ppm	113 ppm	——	——
Monocrotophos (Azodrin)	6923-22-4	0.25 mg/m3	0.75 mg/m3	——	——
Monomethyl aniline (N-Methyl aniline)	100-61-8	0.5 ppm	1.5 ppm	——	X
Monomethyl hydrazine	——	——	——	0.2 ppm	——
Morpholine	110-91-8	20 ppm	30 ppm	——	X
Naled (Dibrom)	300-76-5	3 mg/m3	6 mg/m3	——	X
Naphtha	8030-30-6	100 ppm	150 ppm	——	X
Naphthalene	91-20-3	10 ppm	15 ppm	——	——
alpha-Naphthylamine	134-32-7	——	——	——	——
beta-Naphthylamine	91-59-8	——	——	——	——
Neon	7440-01-9	Simple asphyxiant	——	——	——
Nickel carbonyl (as Ni)	13463-39-3	0.001 ppm	0.003 ppm	——	——
Nickel (as Ni)	7440-02-0	——	——	——	——
Metal and insoluble compounds	——	1 mg/m3	3 mg/m3	——	——
Soluble compounds	——	0.1 mg/m3	0.3 mg/m3	——	——
Nicotine	54-11-5	0.5 mg/m3	1.5 mg/m3	——	X
Nitrapyrin (2-Chloro-6 trichloromethyl pyridine)	1929-82-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Nitric acid	7697-37-2	2 ppm	4 ppm	——	——
Nitric oxide	10102-43-9	25 ppm	38 ppm	——	——
p-Nitroaniline	100-01-6	3 mg/m3	6 mg/m3	——	X
Nitrobenzene	98-95-3	1 ppm	3 ppm	——	X
4-Nitrobiphenyl	92-93-3	——	——	——	——
p-Nitrochlorobenzene	100-00-5	0.5 mg/m3	1.5 mg/m3	——	X
4-Nitrodiphenyl	——	——	——	——	——
Nitroethane	79-24-3	100 ppm	150 ppm	——	——
Nitrogen	7727-37-9	Simple asphyxiant	——	——	——
Nitrogen dioxide	10102-44-0	——	1 ppm	——	——
Nitrogen oxide (Nitrous oxide)	10024-97-2	50 ppm	75 ppm	——	——
Nitrogen trifluoride	7783-54-2	10 ppm	20 ppm	——	——
Nitroglycerin	55-63-0	——	0.1 mg/m3	——	X
Nitromethane	75-52-5	100 ppm	150 ppm	——	——
1-Nitropropane	108-03-2	25 ppm	38 ppm	——	——
2-Nitropropane	79-46-9	10 ppm	20 ppm	——	——
N-Nitrosodimethylamine	62-75-9	——	——	——	——
Nitrotoluene	——	——	——	——	——
o-isomer	88-72-2	2 ppm	4 ppm	——	X
m-isomer	98-08-2	2 ppm	4 ppm	——	X
p-isomer	99-99-0	2 ppm	4 ppm	——	X
Nitrotrichloromethane (Chloropicrin)	76-06-2	0.1 ppm	0.3 ppm	——	——
Nitrous oxide (Nitrogen oxide)	10024-97-2	50 ppm	75 ppm	——	——
Nonane	111-84-2	200 ppm	250 ppm	——	——
Octachloronaphthalene	2234-13-1	0.1 mg/m3	0.3 mg/m3	——	X
Octane	111-65-9	300 ppm	375 ppm	——	——
Oil mist mineral (particulate)	8012-95-1	5 mg/m3	10 mg/m3	——	——
Osmium tetroxide (as Os)	20816-12-0	0.0002 ppm	0.0006 ppm	——	——
Oxalic acid	144-62-7	1 mg/m3	2 mg/m3	——	——
Oxygen difluoride	7783-41-7	——	——	0.05 ppm	——
Ozone	10028-15-6	0.1 ppm	0.3 ppm	——	——
Paper fiber (Cellulose)	9004-34-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Paraffin wax fume	8002-74-2	2 mg/m3	4 mg/m3	——	——
Paraquat	——	——	——	——	——
Respirable fraction	4685-14-7	0.1 mg/m3	0.3 mg/m3	——	X
	1910-42-5
	2074-50-2
Parathion	56-38-2	0.1 mg/m3	0.3 mg/m3	——	X
Particulate polycyclic aromatic hydrocarbons (benzene soluble fraction) (coal tar pitch volatiles)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Particulates not otherwise regulated	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pentaborane	19624-22-7	0.005 ppm	0.015 ppm	——	——
Pentachloronaphthalene	1321-64-8	0.5 mg/m3	1.5 mg/m3	——	X
Pentachlorophenol	87-86-5	0.5 mg/m3	1.5 mg/m3	——	X
Pentaerythritol	115-77-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pentane	109-66-0	600 ppm	750 ppm	——	——
2-Pentanone (methyl propyl ketone)	107-87-9	200 ppm	250 ppm	——	——
Perchloroethylene (tetrachloroethylene)	127-18-4	25 ppm	38 ppm	——	——
Perchloromethyl mercaptan	594-42-3	0.1 ppm	0.3 ppm	——	——
Perchloryl fluoride	7616-94-6	3 ppm	6 ppm	——	——
Perlite	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Petroleum distillates (Naptha, rubber solvent)	——	100 ppm	150 ppm	——	——
Phenacyl chloride (a-Chloroacetophenone)	532-21-4	0.05 ppm	0.15 ppm	——	——
Phenol	108-95-2	5 ppm	10 ppm	——	X
Phenothiazine	92-84-2	5 mg/m3	10 mg/m3	——	X
p-Phenylene diamine	106-50-3	0.1 mg/m3	0.3 mg/m3	——	X
Phenyl ether (vapor)	101-84-8	1 ppm	3 ppm	——	——
Phenyl ether-diphenyl mixture (vapor)	——	1 ppm	3 ppm	——	——
Phenylethylene (Styrene)	100-42-5	50 ppm	100 ppm	——	——
Phenyl glycidyl ether (PGE)	122-60-1	1 ppm	3 ppm	——	——
Phenylhydrazine	100-63-0	5 ppm	10 ppm	——	X
Phenyl mercaptan	108-98-5	0.5 ppm	1.5 ppm	——	——
Phenylphosphine	638-21-1	——	——	0.05 ppm	——
Phorate	298-02-2	0.05 mg/m3	0.2 mg/m3	——	X
Phosdrin (Mevinphos)	7786-34-7	0.01 ppm	0.03 ppm	——	X
Phosgene (carbonyl chloride)	75-44-5	0.1 ppm	0.3 ppm	——	——
Phosphine	7803-51-2	0.3 ppm	1 ppm	——	——
Phosphoric acid	7664-38-2	1 mg/m3	3 mg/m3	——	——
Phosphorus (yellow)	7723-14-0	0.1 mg/m3	0.3 mg/m3	——	——
Phosphorous oxychloride	10025-87-3	0.1 ppm	0.3 ppm	——	——
Phosphorus pentachloride	10026-13-8	0.1 ppm	0.3 ppm	——	——
Phosphorus pentasulfide	1314-80-3	1 mg/m3	3 mg/m3	——	——
Phosphorus trichloride	12-2-19	0.2 ppm	0.5 ppm	——	——
Phthalic anhydride	85-44-9	1 ppm	3 ppm	——	——
m-Phthalodinitrile	626-17-5	5 mg/m3	10 mg/m3	——	——
Picloram	1918-02-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Picric acid (2, 4, 6-Trinitrophenol)	88-89-1	0.1 mg/m3	0.3 mg/m3	——	X
Pindone (2-Pivalyl-1, 3-indandione, Pival)	83-26-1	0.1 mg/m3	0.3 mg/m3	——	——
Piperazine dihydrochloride	142-64-3	5 mg/m3	10 mg/m3	——	——
Pival (Pindone)	83-26-1	0.1 mg/m3	0.3 mg/m3	——	——
Plaster of Paris	26499-65-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Platinum (as Pt)	7440-06-4	——	——	——	——
Metal	——	1 mg/m3	3 mg/m3	——	——
Soluble salts	——	0.002 mg/m3	0.006 mg/m3	——	——
Polychlorobiphenyls (Chlorodiphenyls)	——	——	——	——	——
42% Chlorine (PCB)	53469-21-9	1 mg/m3	3 mg/m3	——	X
54% Chlorine (PCB)	11097-69-1	0.5 mg/m3	1.5 mg/m3	——	X
Portland cement	65997-15-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Potassium hydroxide	1310-58-3	——	——	2 mg/m3	——
Propane	74-98-6	1,000 ppm	1,250 ppm	——	——
Propargyl alcohol	107-19-7	1 ppm	3 ppm	——	X
beta-Propiolactone	57-57-8	——	——	——	——
Propionic acid	79-09-4	10 ppm	20 ppm	——	——
Propoxur (Baygon)	114-26-1	0.5 mg/m3	1.5 mg/m3	——	——
n-Propyl acetate	109-60-4	200 ppm	250 ppm	——	——
n-Propyl alcohol	71-23-8	200 ppm	250 ppm	——	X
n-Propyl nitrate	627-13-4	25 ppm	40 ppm	——	——
Propylene	——	Simple asphyxiant	——	——	——
Propylene dichloride (1, 2-Dichloropropane)	78-87-5	75 ppm	110 ppm	——	——
Propylene glycol dinitrate	6423-43-4	0.05 ppm	0.15 ppm	——	X
Propylene glycol monomethyl ether	107-98-2	100 ppm	150 ppm	——	——
Propylene imine	75-55-8	2 ppm	4 ppm	——	X
Propylene oxide (1,2-Epoxypropane)	75-56-9	20 ppm	30 ppm	——	——
Propyne (Methyl acetylene)	74-99-7	1,000 ppm	1,250 ppm	——	——
Pyrethrum	8003-34-7	5 mg/m3	10 mg/m3	——	——
Pyridine	110-86-1	5 ppm	10 ppm	——	——
Pyrocatachol (Catechol)	120-80-9	5 ppm	10 ppm	——	X
Quinone (p-Benzoquinone)	106-51-4	0.1 ppm	0.3 ppm	——	——
RDX (Cyclonite)	——	1.5 mg/m3	3 mg/m3	——	X
Resorcinol	108-46-3	10 ppm	20 ppm	——	——
Rhodium (as Rh)	7440-16-6	——	——	——	——
Insoluble compounds, metal fumes and dusts	——	0.1 mg/m3	0.3 mg/m3	——	——
Soluble compounds, salts	——	0.001 mg/m3	0.003 mg/m3	——	——
Ronnel	299-84-3	10 mg/m3	20 mg/m3	——	——
Rosin core solder, pyrolysis products (as formaldehyde)	8050-09-7	0.1 mg/m3	0.3 mg/m3	——	——
Rotenone	83-79-4	5 mg/m3	10 mg/m3	——	——
Rouge	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Rubber solvent (naphtha)	8030-30-6	100 ppm	150 ppm	——	——
Selenium compounds (as Se)	7782-49-2	0.2 mg/m3	0.6 mg/m3	——	——
Selenium hexafluoride (as Se)	7783-79-1	0.05 ppm	0.15 ppm	——	——
Sesone (Crag herbicide)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sevin (Carbaryl)	63-25-2	5 mg/m3	10 mg/m3	——	——
Silane (see Silicon tetrahydride)	7803-62-5	5 ppm	10 ppm	——	——
Silica, amorphous, precipitated and gel	112926-00-8	6 mg/m3	12 mg/m3	——	——
Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica	61790-53-2	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Silica, crystalline cristobalite	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	14464-46-1	0.05 mg/m3	0.15 mg/m3	——	——
Silica, crystalline quartz	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	14808-60-7	0.1 mg/m3	0.3 mg/m3	——	——
Silica, crystalline tripoli (as quartz)	——	——	——	——	——
Respirable fraction	1317-95-9	0.1 mg/m3	0.3 mg/m3	——	——
Silica, crystalline tridymite	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	15468-32-3	0.05 mg/m3	0.15 mg/m3	——	——
Silica, fused	——	——	——	——	——
Respirable fraction	60676-86-0	0.1 mg/m3	0.3 mg/m3	——	——
Silicates (less than 1% crystalline silica )	——	——	——	——	——
Mica	——	——	——	——	——
Respirable fraction	12001-26-2	3 mg/m3	6 mg/m3	——	——
Soapstone	——	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Talc (containing asbestos)	——	——	——	——	——
Talc (containing no asbestos)	——	——	——	——	——
Respirable fraction	14807-96-6	2 mg/m3	4 mg/m3	——	——
Tremolite	——	——	——	——	——
Silicon	7440-21-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Silicon carbide	409-21-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Silicon tetrahydride (Silane)	7803-62-5	5 ppm	10 ppm	——	——
Silver, metal dust and soluble compounds (as Ag)	7440-22-4	0.01 mg/m3	0.03 mg/m3	——	——
Soapstone	——	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Sodium azide (as HN3 or NaN3)	26628-22-8	——	——	0.1 ppm	X
Sodium bisulfite	7631-90-5	5 mg/m3	10 mg/m3	——	——
Sodium-2, 4-dichloro-phenoxyethyl sulfate (Crag herbicide)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sodium fluoroacetate	62-74-8	0.05 mg/m3	0.15 mg/m3	——	X
Sodium hydroxide	1310-73-2	——	——	2 mg/m3	——
Sodium metabisulfite	7681-57-4	5 mg/m3	10 mg/m3	——	——
Starch	9005-25-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Stibine	7803-52-3	0.1 ppm	0.3 ppm	——	——
Stoddard solvent	8052-41-3	100 ppm	150 ppm	——	——
Strychnine	57-24-9	0.15 mg/m3	0.45 mg/m3	——	——
Styrene (Phenylethylene, Vinyl benzene)	100-42-5	50 ppm	100 ppm	——	——
Subtilisins	9014-01-1	——	0.00006 mg/m3	——	——
			(60 min.)
Sucrose	57-50-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sulfotep (TEDP)	3689-24-5	0.2 mg/m3	0.6 mg/m3	——	X
Sulfur dioxide	7446-09-5	2 ppm	5 ppm	——	——
Sulfur hexafluoride	2551-62-4	1,000 ppm	1,250 ppm	——	——
Sulfuric acid	7664-93-9	1 mg/m3	3 mg/m3	——	——
Sulfur monochloride	10025-67-9	——	——	1 ppm	——
Sulfur pentafluoride	5714-22-1	——	——	0.01 ppm	——
Sulfur tetrafluoride	7783-60-0	——	——	0.1 ppm	——
Sulfuryl fluoride	2699-79-8	5 ppm	10 ppm	——	——
Sulprofos	35400-43-2	1 mg/m3	3 mg/m3	——	——
Systox (Demeton)	8065-48-3	0.01 ppm	0.03 ppm	——	X
2, 4, 5-T	93-76-5	10 mg/m3	20 mg/m3	——	——
Talc (containing asbestos)	——	——	——	——	——
Talc (containing no asbestos)	——	——	——	——	——
Respirable fraction	14807-96-6	2 mg/m3	4 mg/m3	——	——
Tantalum	——	——	——	——	——
Metal and oxide dusts	7440-25-7	5 mg/m3	10 mg/m3	——	——
TDI (Toluene-2, 4-diisocyanate)	584-84-9	0.005 ppm	0.02 ppm	——	——
TEDP (Sulfotep)	3689-24-5	0.2 mg/m3	0.6 mg/m3	——	X
Tellurium and compounds (as Te)	13494-80-9	0.1 mg/m3	0.3 mg/m3	——	——
Tellurium hexafluoride (as Te)	7783-80-4	0.02 ppm	0.06 ppm	——	——
Temephos (Abate)	3383-96-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
TEPP	107-49-3	0.004 ppm	0.012 ppm	——	X
Terphenyls	26140-60-3	——	——	0.5 ppm	——
1, 1, 1, 2-Tetrachloro-2, 2-difluoroethane	76-11-0	500 ppm	625 ppm	——	——
1, 1, 2, 2-Tetrachloro-1, 2-difluoroethane	76-12-0	500 ppm	625 ppm	——	——
1, 1, 2, 2-Tetrachloroethane	79-34-5	1 ppm	3 ppm	——	X
Tetrachloroethylene (Perchloroethylene)	127-18-4	25 ppm	38 ppm	——	——
Tetrachloromethane (Carbon tetrachloride)	56-23-5	2 ppm	4 ppm	——	X
Tetrachloronaphthalene	1335-88-2	2 mg/m3	4 mg/m3	——	X
Tetraethyl lead (as Pb)	78-00-2	0.075 mg/m3	0.225 mg/m3	——	X
Tetrahydrofuran	109-99-9	200 ppm	250 ppm	——	——
Tetramethyl lead (as Pb)	75-74-1	0.075 mg/m3	0.225 mg/m3	——	X
Tetramethyl succinonitrile	3333-52-6	0.5 ppm	1.5 ppm	——	X
Tetranitromethane	509-14-8	1 ppm	3 ppm	——	——
Tetrasodium pyrophosphate	7722-88-5	5 mg/m3	10 mg/m3	——	——
Tetryl (2, 4, 6-trinitrophenyl- methylnitramine)	479-45-8	1.5 mg/m3	3 mg/m3	——	X
Thallium (soluble compounds) (as Tl)	7440-28-0	0.1 mg/m3	0.3 mg/m3	——	X
4, 4-Thiobis (6-tert-butyl-m-cresol)	96-69-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Thiodan (Endosulfan)	115-29-7	0.1 mg/m3	0.3 mg/m3	——	X
Thioglycolic acid	68-11-1	1 ppm	3 ppm	——-	X
Thionyl chloride	7719-09-7	——	——	1 ppm	——
Thiram	137-26-8	5 mg/m3	10 mg/m3	——	——
Tin (as Sn)	——	——	——	——	——
Inorganic compounds	7440-31-5	2 mg/m3	4 mg/m3	——	——
Tin (as Sn)	——	——	——	——	——
Organic compounds	7440-31-5	0.1 mg/m3	0.3 mg/m3	——	X
Tin oxide (as Sn)	21651-19-4	2 mg/m3	4 mg/m3	——	——
Titanium dioxide	13463-67-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
TNT (2, 4, 6-Trinitrotoluene)	118-96-7	0.5 mg/m3	1.5 mg/m3	——	X
Toluene	108-88-3	100 ppm	150 ppm	——	——
Toluene-2, 4-diisocyanate (TDI)	584-84-9	0.005 ppm	0.02 ppm	——-	——
m-Toluidine	108-44-1	2 ppm	4 ppm	——	X
o-Toluidine	95-53-4	2 ppm	4 ppm	——	X
p-Toluidine	106-49-0	2.0 ppm	4 ppm	——	X
Toxaphene (Chlorinated camphene)	8001-35-2	0.5 mg/m3	1 mg/m3	——	X
Tremolite	——	——	——	——	——
Tributyl phosphate	126-73-8	0.2 ppm	0.6 ppm	——	——
Trichloroacetic acid	76-03-9	1 ppm	3 ppm	——	——
1, 2, 4-Trichlorobenzene	120-82-1	——	——	5 ppm	——
1, 1, 1-Trichloroethane (Methyl chloroform)	71-55-6	350 ppm	450 ppm	——	——
1, 1, 2-Trichloroethane	79-00-5	10 ppm	20 ppm	——	——
Trichloroethylene	79-01-6	50 ppm	200 ppm	——	——
Trichlorofluoromethane (Fluorotrichloromethane)	75-69-4	——	——	1,000 ppm	——
Trichloromethane (Chloroform)	67-66-3	2 ppm	4 ppm	——	——
Trichloronaphthalene	1321-65-9	5 mg/m3	10 mg/m3	——	X
1, 2, 3-Trichloropropane	96-18-4	10 ppm	20 ppm	——	X
1, 1, 2-Trichloro-1, 2, 2-trifluoroethane	76-13-1	1,000 ppm	1,250 ppm	——	——
Tricyclohexyltin hydroxide (Cyhexatin)	13121-70-5	5 mg/m3	10 mg/m3	——	——
Triethylamine	121-44-8	10 ppm	15 ppm	——	——
Trifluorobromomethane	75-63-8	1,000 ppm	1,250 ppm	——	——
Trimellitic anhydride	552-30-7	0.005 ppm	0.015 ppm	——	——
Trimethylamine	75-50-3	10 ppm	15 ppm	——	——
Trimethyl benzene	25551-13-7	25 ppm	38 ppm	——	——
Trimethyl phosphite	121-45-9	2 ppm	4 ppm	——	——
2, 4, 6-Trinitrophenol (Picric acid)	88-89-1	0.1 mg/m3	0.3 mg/m3	——	X
2, 4, 6-Trinitrophenyl-methylnitramine (Tetryl)	479-45-8	1.5 mg/m3	3 mg/m3	——	X
2, 4, 6-Trinitrotoluene (TNT)	118-96-7	0.5 mg/m3	1.5 mg/m3	——	X
Triorthocresyl phosphate	78-30-8	0.1 mg/m3	0.3 mg/m3	——	X
Triphenyl amine	603-34-9	5 mg/m3	10 mg/m3	——	——
Triphenyl phosphate	115-86-6	3 mg/m3	6 mg/m3	——	——
Tungsten (as W)	7440-33-7	——	——	——	——
Soluble compounds	——	1 mg/m3	3 mg/m3	——	——
Insoluble compounds	——	5 mg/m3	10 mg/m3	——	——
Turpentine	8006-64-2	100 ppm	150 ppm	——	——
Uranium (as U)	7440-61-1	——	——	——	——
Soluble compounds	——	0.05 mg/m3	0.15 mg/m3	——	——
Insoluble compounds	——	0.2 mg/m3	0.6 mg/m3	——	——
n-Valeraldehyde	110-62-3	50 ppm	75 ppm	——	——
Vanadium (as V2O5)	——	——	——	——	——
Respirable fraction	1314-62-1	0.05 mg/m3	0.15 mg/m3	——	——
Vegetable oil mist	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Vinyl acetate	108-05-1	10 ppm	20 ppm	——	——
Vinyl benzene (Styrene)	100-42-5	50 ppm	100 ppm	——	——
Vinyl bromide	593-60-2	5 ppm	10 ppm	——	——
Vinyl chloride (Chloroethylene)	75-01-4	1 ppm	5 ppm	——	——
Vinyl cyanide (Acrylonitrile)	107-13-1	2 ppm	10 ppm	——	——
Vinyl cyclohexene dioxide	106-87-6	10 ppm	20 ppm	——	X
Vinyl toluene	25013-15-4	50 ppm	75 ppm	——	——
Vinylidene chloride (1, 1-Dichloroethylene)	75-35-4	1 ppm	3 ppm	——	——
VM & P Naphtha	8032-32-4	300 ppm	400 ppm	——	——
Warfarin	81-81-2	0.1 mg/m3	0.3 mg/m3	——	——
Welding fumes (total particulate)	——	5 mg/m3	10 mg/m3	——	——
Wood dust	——	——	——	——	——
Nonallergenic; (All woods except allergenics)	——	5 mg/m3	10 mg/m3	——	——
Allergenics (e.g. cedar, mahogany and teak)	——	2.5 mg/m3	5 mg/m3	——	——
Xylenes (ortho, meta, and para isomers) (Dimethylbenzene)	1330-20-7	100 ppm	150 ppm	——	——
m-Xylene alpha, alpha-diamine	1477-55-0	——	——	0.1 mg/m3	X
Xylidine (Dimethylaminobenzene)	1300-73-8	2 ppm	4 ppm	——	X
Yttrium	7440-65-5	1 mg/m3	3 mg/m3	——	——
Zinc chloride fume	7646-85-7	1 mg/m3	2 mg/m3	——	——
Zinc chromate (as CrO3)	Varies with compound	0.05 mg/m3	——	0.1 mg/m3	——
Zinc oxide	1314-13-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m	——	——
Zinc oxide fume	1314-13-2	5 mg/g3	10 mg/m3	——	——
Zinc stearate	557-05-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Zirconium compounds (as Zr)	7440-67-2	5 mg/m3	10 mg/m3	——	——

Chapter 296-840 WAC

RESPIRABLE CRYSTALLINE SILICA

NEW SECTION

WAC 296-840-095 Definitions.

For the purposes of this chapter the following definitions apply:

Action level. A concentration of airborne respirable crystalline silica of 25 μg/m3, calculated as an 8-hour time-weighted average (TWA).

Competent person. An individual who is capable of identifying existing and foreseeable respirable crystalline silica hazards in the workplace and who has authorization to take prompt corrective measures to eliminate or minimize them. The competent person must have the knowledge and ability necessary to fulfill the responsibilities set forth in WAC 296-840-140.

Construction work. All or any part of excavation, construction, erection, alteration, repair, demolition, and dismantling, of buildings and other structures and all operations in connection therewith; the excavation, construction, alteration and repair of sewers, trenches, caissons, conduits, pipe lines, roads and all operations pertaining thereto; the moving of buildings and other structures, and to the construction, alteration, repair, or removal of wharfs, docks, bridges, culverts, trestles, piers, abutments or any other construction, alteration, repair or removal work related thereto.

Director. The director of the department of labor and industries or his/her authorized representative.

DOSH. The division of occupational safety and health, Washington state department of labor and industries.

Employee exposure. The exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.

High-efficiency particulate air (HEPA) filter. A filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter.

Objective data. Information, such as air monitoring data from industry-wide surveys or calculations based on the composition of a substance, demonstrating employee exposure to respirable crystalline silica associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.

Permissible exposure limit (PEL). A concentration of airborne respirable crystalline silica of 50 μg/m3, calculated as an 8-hour TWA.

Physician or other licensed health care professional (PLHCP). An individual whose legally permitted scope of practice (i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required by WAC 296-840-145.

Regulated area. An area, demarcated by the employer, where an employee's exposure to airborne concentrations of respirable crystalline silica exceeds, or can reasonably be expected to exceed, the PEL.

Respirable crystalline silica. Quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air quality – Particle size fraction definitions for health-related sampling.

Specialist. An American Board Certified Specialist in Pulmonary Disease or an American Board Certified Specialist in Occupational Medicine.

NEW SECTION

WAC 296-840-100 Scope and application.

This chapter applies to all occupational exposures to respirable crystalline silica, except for the following:

(1) Where employee exposure results from the processing of sorptive clays.

(2) Where documented objective data demonstrates that employee exposures to respirable crystalline silica will remain below 25 micrograms per cubic meter of air (25 μg/m3) as an 8-hour TWA under any foreseeable conditions.

NEW SECTION

WAC 296-840-105 Exposure assessment.

This section applies to all occupational exposures except for tasks performed according to the requirements in WAC 296-840-110.

(1) Permissible exposure limit (PEL). You must ensure that no employee is exposed to an airborne concentration of respirable crystalline silica in excess of the 8-hour TWA.

(2) Exposure assessment. You must assess the exposure of each employee who is or may reasonably be expected to be exposed to respirable crystalline silica at or above the action level in accordance with either the performance option in (a) of this subsection or the scheduled monitoring option in (b) of this subsection.

(a) Performance option. You must assess the 8-hour TWA for each employee on the basis of any combination of air monitoring data or objective data sufficient to accurately characterize employee exposures to respirable crystalline silica.

(b) Scheduled monitoring option:

(i) You must perform initial monitoring to assess the 8-hour TWA for each employee on the basis of personal breathing zone air samples that reflect the exposures of employees on each shift, for each job classification, in each work area.

(ii) Where several employees perform the same tasks on the same shift and in the same work area, you may sample a representative fraction of these employees in order to meet this requirement.

(iii) In representative sampling, you must sample the employee(s) who are expected to have the highest exposure to respirable crystalline silica.

(iv) If initial monitoring indicates that employee exposures are below the action level, you may discontinue monitoring for those employees whose exposures are represented by such monitoring.

(v) Where the most recent exposure monitoring indicates that employee exposures are at or above the action level but at or below the PEL, you must repeat such monitoring within six months of the most recent monitoring.

(vi) Where the most recent exposure monitoring indicates that employee exposures are above the PEL, the employer shall repeat such monitoring within three months of the most recent monitoring.

(vii) Where the most recent (noninitial) exposure monitoring indicates that employee exposures are below the action level, you must repeat such monitoring within six months of the most recent monitoring until two consecutive measurements, taken seven or more days apart, are below the action level, at which time the employer may discontinue monitoring for those employees whose exposures are represented by such monitoring, except as otherwise provided in subsection (3) of this section.

(3) Reassessment of exposures. You must reassess exposures whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional exposures at or above the action level, or when the employer has any reason to believe that new or additional exposures at or above the action level have occurred.

(4) Methods of sample analysis. You must ensure that all samples taken to satisfy the monitoring requirements of subsection (2) of this section are evaluated by a laboratory that analyzes air samples for respirable crystalline silica in accordance with the procedures in WAC 296-840-165 Appendix A—Methods of sample analysis of this chapter.

(5) Employee notification of assessment results.

(a) Individually notify each affected employee in writing of the results of that assessment or post the results in an appropriate location accessible to all affected employees in accordance with the following:

(i) Construction employers must notify affected employees within five working days after receiving any results of an exposure assessment in accordance with this rule.

(ii) All other employers must notify affected employees within fifteen working days after receiving any results of an exposure assessment in accordance with this rule.

(b) Whenever an exposure assessment indicates that employee exposure is above the PEL, you must describe in the written notification the corrective action being taken to reduce employee exposure to or below the PEL.

(6) Observation of monitoring.

(a) Where air monitoring is performed to comply with the requirements of this chapter, you must provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to respirable crystalline silica.

(b) When observation of monitoring requires entry into an area where the use of protective clothing or equipment is required for any workplace hazard, you must provide the observer with protective clothing and equipment at no cost and shall ensure that the observer uses such clothing and equipment.

NEW SECTION

WAC 296-840-110 Specified exposure control methods.

This section applies to construction work and other occupational exposures where the task performed is indistinguishable from a construction task listed in Table 1 of this section and the task will not be performed regularly in the same environment and conditions.

(1) For each employee engaged in a task identified in Table 1 of this section, you must fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task in Table 1 of this section, unless you assess and limit the exposure of the employee to respirable crystalline silica in accordance with WAC 296-840-105.

(2) When implementing the control measures specified in Table 1 of this section, you must:

(a) For tasks performed indoors or in enclosed areas, provide a means of exhaust as needed to minimize the accumulation of visible airborne dust;

(b) For tasks performed using wet methods, apply water at flow rates sufficient to minimize release of visible dust;

(i) Is maintained as free as practicable from settled dust;

(ii) Has door seals and closing mechanisms that work properly;

(iii) Has gaskets and seals that are in good condition and working properly;

(iv) Is under positive pressure maintained through continuous delivery of fresh air;

(v) Has intake air that is filtered through a filter that is ninety-five percent efficient in the 0.3-10.0 μm range (e.g., MERV-16 or better); and

(vi) Has heating and cooling capabilities.

(3) Where an employee performs more than one task in Table 1 of this section during the course of a shift, and the total duration of all tasks combined is more than four hours, the required respiratory protection for each task is the respiratory protection specified for more than four hours per shift. If the total duration of all tasks in Table 1 of this section combined is less than four hours, the required respiratory protection for each task is the respiratory protection specified for less than four hours per shift.

Table 1

Specified Exposure Control Methods When Working With Materials Containing Crystalline Silica


Equipment/ Task	Engineering and Work Practice Control Methods	Required Respiratory Protection and Minimum Assigned Protection Factor (APF)
Equipment/ Task	Engineering and Work Practice Control Methods	≤ 4 hours/shift	> 4 hours/shift
(i) Stationary masonry saws	Use saw equipped with integrated water delivery system that continuously feeds water to the blade.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
(ii) Hand-held power saws (any blade diameter)	Use saw equipped with integrated water delivery system that continuously feeds water to the blade.
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	- When used outdoors. - When used indoors or in an enclosed area.	None APF 10	APF 10 APF 10
(iii) Hand-held power saws for cutting fiber-cement board (with blade diameter of 8 inches or less)	For tasks performed outdoors only:
	Use saw equipped with commercially available dust collection system.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency.
(iv) Walk-behind saws	Use saw equipped with integrated water delivery system that continuously feeds water to the blade.
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	- When used outdoors. - When used indoors or in an enclosed area.	None APF 10	None APF 10
(v) Drivable saws	For tasks performed outdoors only:
	Use saw equipped with integrated water delivery system that continuously feeds water to the blade.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
(vi) Rig-mounted core saws or drills	Use tool equipped with integrated water delivery system that supplies water to cutting surface.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
(vii) Hand-held and stand-mounted drills (including impact and rotary hammer drills)	Use drill equipped with commercially available shroud or cowling with dust collection system.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism.
	Use a HEPA-filtered vacuum when cleaning holes.
(viii) Dowel drilling rigs for concrete	For tasks performed outdoors only:
	Use shroud around drill bit with a dust collection system. Dust collector must have a filter with 99% or greater efficiency and a filter-cleaning mechanism.	APF 10	APF 10
	Use a HEPA-filtered vacuum when cleaning holes.
(ix) Vehicle-mounted drilling rigs for rock and concrete	Use dust collection system with close capture hood or shroud around drill bit with a low-flow water spray or wet the dust at the discharge point from the dust collector.	None	None
	OR
	Operate from within an enclosed cab and use water for dust suppression on drill bit.	None	None
(x) Jackhammers and hand-held powered chipping tools	Use tool with water delivery system that supplies a continuous stream or spray of water at the point of impact.
	- When used outdoors. - When used indoors or in an enclosed area.	None APF 10	APF 10 APF 10
	OR
	Use tool equipped with commercially available shroud and dust collection system.
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism.
	- When used outdoors. - When used indoors or in an enclosed area.	None APF 10	APF 10 APF 10
(xi) Hand-held grinders for mortar removal (i.e., tuckpointing)	Use grinder equipped with commercially available shroud and dust collection system.	APF 10	APF 25
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and cyclonic preseparator or filter-cleaning mechanism.
(xii) Hand-held grinders for uses other than mortar removal	For tasks performed outdoors only:
(xii) Hand-held grinders for uses other than mortar removal	Use grinder equipped with integrated water delivery system that continuously feeds water to the grinding surface.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	OR
	Use grinder equipped with commercially available shroud and dust collection system.
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and a cyclonic preseparator or filter-cleaning mechanism.
	- When used outdoors. - When used indoors or in an enclosed area.	None None	None APF 10
(xiii) Walk-behind milling machines and floor grinders	Use machine equipped with integrated water delivery system that continuously feeds water to the cutting surface.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	OR
	Use machine equipped with dust collection system recommended by the manufacturer.	None	None
	Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions.
	Dust collector must provide the air flow recommended by the manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism.
	When used indoors or in an enclosed area, use a HEPA-filtered vacuum to remove loose dust in between passes.
(xiv) Small drivable milling machines (less than half-lane)	Use machine equipped with supplemental water sprays designed to suppress dust. Water must be combined with a surfactant.	None	None
	Operate and maintain machine to minimize dust emissions.
(xv) Large drivable milling machines (half-lane and larger)	For cuts of any depth on asphalt only:	None	None
(xv) Large drivable milling machines (half-lane and larger)	Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust.
	Operate and maintain machine to minimize dust emissions.
	For cuts of four inches in depth or less on any substrate:	None	None
	Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust.
	Operate and maintain machine to minimize dust emissions.
	OR
	Use a machine equipped with supplemental water spray designed to suppress dust. Water must be combined with a surfactant.
	Operate and maintain machine to minimize dust emissions.
(xvi) Crushing machines	Use equipment designed to deliver water spray or mist for dust suppression at crusher and other points where dust is generated (e.g., hoppers, conveyers, sieves/sizing or vibrating components, and discharge points).	None	None
	Operate and maintain machine in accordance with manufacturer's instructions to minimize dust emissions.
	Use a ventilated booth that provides fresh, climate-controlled air to the operator, or a remote control station.
(xvii) Heavy equipment and utility vehicles used to abrade or fracture silica-containing materials (e.g., hoe-ramming, rock ripping) or used during demolition activities involving silica-containing materials	Operate equipment from within an enclosed cab.	None	None
	When employees outside of the cab are engaged in the task, apply water and/or dust suppressants as necessary to minimize dust emissions.	None	None
(xviii) Heavy equipment and utility vehicles for tasks such as grading and excavating but not including: Demolishing, abrading or fracturing silica-containing materials	Apply water and/or dust suppressants as necessary to minimize dust emissions.	None	None
	OR
	When the equipment operator is the only employee engaged in the task, operate equipment from within an enclosed cab.	None	None

NEW SECTION

WAC 296-840-115 Regulated areas.

This section does not apply to occupational respirable crystalline silica exposures in construction work.

(1) Establishment. You must establish a regulated area wherever an employee's exposure to airborne concentrations of respirable crystalline silica is, or can reasonably be expected to be, in excess of the PEL.

(2) Demarcation. You must demarcate the regulated areas from the rest of the workplace in a manner that minimizes the number of employees exposed to respirable crystalline silica within the regulated area.

(3) You must post signs at all entrances to regulated areas that bear the legend specified in WAC 296-840-150(2).

(4) Access. You must limit access to regulated areas to:

(a) Persons authorized by the employer and required by work duties to be present in the regulated area;

(b) Any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring procedures under WAC 296-840-105; and

(5) Provision of respirators. You must provide each employee and the employee's designated representative entering a regulated area with an appropriate respirator in accordance with WAC 296-840-125 and must require each employee and the employee's designated representative to use the respirator while in a regulated area.

NEW SECTION

WAC 296-840-120 Methods of compliance.

This section does not apply to tasks listed and performed in accordance with Table 1 of WAC 296-840-110 Specified exposure control methods.

(1) Engineering and work practice controls. You must use engineering and work practice controls to reduce and maintain employee exposure to respirable crystalline silica to or below the PEL, unless the employer can demonstrate that such controls are not feasible. Wherever such feasible engineering and work practice controls are not sufficient to reduce employee exposure to or below the PEL, you must nonetheless use them to reduce employee exposure to the lowest feasible level and must supplement them with the use of respiratory protection that complies with the requirements of WAC 296-840-125.

(2) Abrasive blasting. In addition to the requirements of this section, you must comply with chapter 296-818 WAC, safety standards for abrasive blasting and other applicable DOSH standards where abrasive blasting is conducted using crystalline silica containing blasting agents, or where abrasive blasting is conducted on substrates that contain crystalline silica.

NEW SECTION

WAC 296-840-125 Respiratory protection.

(1) Where respiratory protection is required by this section, you must provide each employee an appropriate respirator that complies with the requirements of this section and chapter 296-842 WAC, Respirators.

(2) Respiratory protection is required:

(a) Where exposures exceed the PEL during periods necessary to install or implement feasible engineering and work practice controls;

(b) Where exposures exceed the PEL during tasks, such as certain maintenance and repair tasks, for which engineering and work practice controls are not feasible;

(c) During tasks for which an employer has implemented all feasible engineering and work practice controls and such controls are not sufficient to reduce exposures to or below the PEL;

(d) During periods when an employee or employees are in a regulated area; and

(e) Where specified for tasks performed according to the requirements in Table 1 of WAC 296-840-110 Specified exposure control methods.

NEW SECTION

WAC 296-840-130 Respiratory protection program.

(1) Where respirator use is required by this chapter, you must institute a respiratory protection program in accordance with chapter 296-842 WAC, Respirators.

(2) Specified exposure control methods. For tasks listed in Table 1 of WAC 296-840-110, if you fully and properly implement the engineering controls, work practices, and respiratory protection described in Table 1 of WAC 296-840-110, you will be considered to be in compliance with WAC 296-840-125(1) and the requirements for selection of respirators in chapter 296-842 WAC with regard to exposure to respirable crystalline silica.

NEW SECTION

WAC 296-840-135 Housekeeping.

(1) You must not allow dry sweeping or dry brushing where such activity could contribute to employee exposure to respirable crystalline silica unless wet sweeping, HEPA-filtered vacuuming or other methods that minimize the likelihood of exposure are not feasible.

(2) You must not allow compressed air to be used to clean clothing or surfaces where such activity could contribute to employee exposure to respirable crystalline silica unless:

(a) The compressed air is used in conjunction with a ventilation system that effectively captures the dust cloud created by the compressed air; or

(b) No alternative method is feasible.

NEW SECTION

WAC 296-840-140 Written exposure control plan.

(1) You must establish and implement a written exposure control plan that contains at least the following elements:

(a) A description of the tasks in the workplace that involve exposure to respirable crystalline silica;

(b) A description of the engineering controls, work practices, and respiratory protection used to limit employee exposure to respirable crystalline silica for each task; and

(2) You must review and evaluate the effectiveness of the written exposure control plan at least annually and update it as necessary.

(3) You must make the written exposure control plan readily available for examination and copying, upon request, to each employee covered by this chapter, their designated representatives, and the director.

(4) In addition to the above written exposure control plan requirements, you must include the following elements for construction work:

(a) A description of the procedures used to restrict access to work areas, when necessary, to minimize the number of employees exposed to respirable crystalline silica and their level of exposure, including exposures generated by other employers or sole proprietors.

(b) A competent person to make frequent and regular inspections of job sites, materials, and equipment to implement the written exposure control plan.

NEW SECTION

WAC 296-840-145 Medical surveillance.

(1) Medical surveillance must be made available at no cost to the employee and at a reasonable time and place for any employee:

(a) Doing construction tasks and required by this chapter to use a respirator for thirty or more days per year.

(b) Doing work other than construction tasks and will be occupationally exposed to respirable crystalline silica at or above the action level for thirty or more days per year.

(2) You must ensure that all medical examinations and procedures required by this chapter are performed by a PLHCP as defined in WAC 296-840-095.

(3) Initial examination. You must make available an initial (baseline) medical examination within thirty days after initial assignment, unless the employee has received a medical examination that meets the requirements of this chapter within the last three years. The examination must consist of:

(a) A medical and work history, with emphasis on: Past, present, and anticipated exposure to respirable crystalline silica, dust, and other agents affecting the respiratory system; any history of respiratory system dysfunction, including signs and symptoms of respiratory disease (e.g., shortness of breath, cough, wheezing); smoking status and history; and history of tuberculosis. The history of tuberculosis should include completion of the Washington state department of labor and industries form F252-113-000, Adult Tuberculosis Screening Tool for Workers Exposed to Respirable Crystalline Silica, located in WAC 296-840-175, Appendix C of this chapter;

(b) A physical examination with special emphasis on the respiratory system;

(c) A chest X-ray (a single posteroanterior radiographic projection or radiograph of the chest at full inspiration recorded on either film (no less than 14 x 17 inches and no more than 16 x 17 inches) or digital radiography systems), interpreted and classified according to the International Labour Office (ILO) International Classification of Radiographs of Pneumoconioses by a NIOSH-certified B Reader;

(d) A pulmonary function test to include forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) and FEV1/FVC ratio, administered by a spirometry technician with a current certificate from a NIOSH-approved spirometry course;

(e) Testing for latent tuberculosis infection; and

(f) Any other test deemed appropriate by the PLHCP.

(4) Periodic examinations. You must make available medical examinations that include the procedures described in this section, except for subsection (3)(e) of this section, at least every three years or more frequently if recommended by the PLHCP.

(5) Information provided to the PLHCP. You must ensure that the examining PLHCP has a copy of this standard, and must provide the PLHCP with the following information:

(a) A description of the employee's former, current, and anticipated duties as they relate to the employee's occupational exposure to respirable crystalline silica;

(b) The employee's former, current, and anticipated levels of occupational exposure to respirable crystalline silica;

(c) A description of any personal protective equipment used or to be used by the employee, including when and for how long the employee has used or will use that equipment; and

(d) Information from records of employment-related medical examinations previously provided to the employee and currently within the control of the employer.

(6) PLHCP's written medical report for the employee. You must ensure that the PLHCP explains to the employee the results of the medical examination and provides each employee with a written medical report within thirty days of each medical examination performed. The written report must contain:

(a) A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;

(b) Any recommended limitations on the employee's use of respirators;

(d) A statement that the employee should be examined by a specialist under subsection (9)(a) of this section if the chest X-ray provided in accordance with this chapter is classified as 1/0 or higher by the B Reader, or if referral to a specialist is otherwise deemed appropriate by the PLHCP.

(7) PLHCP's written medical opinion for employers. You must obtain a written medical opinion from the PLHCP within thirty days of the medical examination. The written opinion must contain only the following:

(a) The date of the examination;

(b) A statement that the examination has met the requirements of this section;

(d) If the employee provides written authorization, the written opinion shall also contain either or both of the following:

(i) Any recommended limitations on the employee's exposure to respirable crystalline silica;

(ii) A statement that the employee should be examined by a specialist under subsection (9)(a) of this section if the chest X-ray provided in accordance with this chapter is classified as 1/0 or higher by the B Reader, or if referral to a specialist is otherwise deemed appropriate by the PLHCP.

(8) You must ensure that each employee receives a copy of the written medical opinion described in subsection (7) of this section within thirty days of each medical examination performed.

(9) Additional examinations.

(a) If the PLHCP's written medical opinion indicates that an employee should be examined by a specialist, you must make available a medical examination by a specialist within thirty days after receiving the PLHCP's written opinion. You must ensure that:

(i) The examining specialist is provided with all of the information that the employer is obligated to provide to the PLHCP in accordance with subsection (5) of this section.

(ii) The specialist explains to the employee the results of the medical examination and provides each employee with a written medical report within thirty days of the examination. The written report shall meet the requirements of subsection (6)(a), (b), and (c) of this section.

(b) You must obtain a written opinion from the specialist within thirty days of the medical examination. The written opinion shall meet the requirements of subsection (7), except (b) and (d)(ii) of this section.

NEW SECTION

WAC 296-840-150 Communication of respirable crystalline silica hazards to employees.

(1) Regarding hazard communication you must:

(a) Include respirable crystalline silica in the program established to comply with chapter 296-901 WAC, Globally harmonized system for hazard communication.

(b) Ensure that each employee has access to labels on containers of crystalline silica and safety data sheets, and is trained in accordance with WAC 296-901-14016 and subsection (3) of this section. The employer shall ensure that at least the following hazards are addressed: Cancer, lung effects, immune system effects, and kidney effects.

(2) Signs. Where a regulated area is established you must post signs at all entrances to the regulated areas that bear the following legend:

DANGER

RESPIRABLE CRYSTALLINE SILICA

MAY CAUSE CANCER

CAUSES DAMAGE TO LUNGS

WEAR RESPIRATORY PROTECTION IN THIS AREA

AUTHORIZED PERSONNEL ONLY

(3) Regarding employee information and training, you must ensure that each employee covered by this chapter can demonstrate knowledge and understanding of at least the following:

(a) The health hazards associated with exposure to respirable crystalline silica;

(b) Specific tasks in the workplace that could result in exposure to respirable crystalline silica;

(c) Specific measures you have implemented to protect employees from exposure to respirable crystalline silica, including engineering controls, work practices, and respirators to be used;

(d) The contents of this chapter;

(e) The purpose and a description of the medical surveillance program required by WAC 296-840-145, and notice that the medical surveillance program under this chapter is not intended to reduce a worker's legal rights under Title 51 RCW;

(f) The identity of the competent person designated by the employer in accordance with WAC 296-840-140 (4)(b).

(4) You must make a copy of this chapter readily available without cost to each employee covered by this chapter.

NEW SECTION

WAC 296-840-155 Recordkeeping.

(1) Air monitoring data.

(a) You must make and maintain an accurate record of all exposure measurements taken to assess employee exposure to respirable crystalline silica, as prescribed in WAC 296-840-105(2). This record must include at least the following information:

(i) The date of measurement for each sample taken;

(ii) The task monitored;

(iii) Sampling and analytical methods used;

(iv) Number, duration, and results of samples taken;

(v) Identity of the laboratory that performed the analysis;

(vi) Type of personal protective equipment, such as respirators, worn by the employees monitored; and

(vii) Name, Social Security number, and job classification of all employees represented by the monitoring, indicating which employees were actually monitored.

(b) You must ensure that exposure records are maintained and made available in accordance with chapter 296-802 WAC, Employee medical and exposure records.

(2) Objective data.

(a) You must make and maintain an accurate record of all objective data relied upon to comply with the requirements of this chapter. This record must include at least the following information:

(i) The crystalline silica-containing material in question;

(ii) The source of the objective data;

(iii) The testing protocol and results of testing;

(iv) A description of the process, task, or activity on which the objective data were based; and

(v) Other data relevant to the process, task, activity, material, or exposures on which the objective data were based.

(b) You must ensure that objective data are maintained and made available in accordance with chapter 296-802 WAC, Employee medical and exposure records.

(3) Medical surveillance.

(a) You must make and maintain an accurate record for each employee covered by medical surveillance under WAC 296-840-145. The record must include the following information about the employee:

(i) Name and Social Security number;

(ii) A copy of the PLHCPs' and specialists' written medical opinions; and

(iii) A copy of the information provided to the PLHCPs and specialists.

(b) You must ensure that medical records are maintained and made available in accordance with chapter 296-802 WAC, Employee medical and exposure records.

NEW SECTION

WAC 296-840-160 Effective dates.

This chapter becomes effective on April 23, 2018. Employers must comply with obligations of this chapter in accordance with the following:

(1) For occupational exposures to respirable crystalline silica in construction work, employers must comply with all obligations of this chapter by October 1, 2018. This includes the sample analysis requirement.

(2) For all occupational exposures to respirable crystalline silica other than construction work, employers must comply with this chapter by July 1, 2019, except as follows:

(a) Where employee exposure to respirable crystalline silica is above the PEL for thirty or more days per year medical surveillance requirements in WAC 296-840-145 must be complied with by July 1, 2019.

(b) Where employee exposure to respirable crystalline silica is at or above the action level for thirty or more days per year medical surveillance requirements in WAC 296-840-145 must be complied with by June 23, 2020.

(c) For hydraulic fracturing operations in the oil and gas industry, obligations for engineering controls under WAC 296-840-120(1) begin July 1, 2022.

NEW SECTION

WAC 296-840-165 Appendix A—Methods of sample analysis—Mandatory.

This appendix specifies the procedures for analyzing air samples for respirable crystalline silica, as well as the quality control procedures that employers must ensure that laboratories use when performing an analysis required under WAC 296-840-105(4). Employers must ensure that such a laboratory:

(1) Evaluates all samples using the procedures specified in one of the following analytical methods: OSHA ID-142; NMAM 7500; NMAM 7602; NMAM 7603; MSHA P-2; or MSHA P-7;

(2) Is accredited to ANS/ISO/IEC Standard 17025:2005 with respect to crystalline silica analyses by a body that is compliant with ISO/IEC Standard 17011:2004 for implementation of quality assessment programs;

(3) Uses the most current National Institute of Standards and Technology (NIST) or NIST traceable standards for instrument calibration or instrument calibration verification;

(4) Implements an internal quality control (QC) program that evaluates analytical uncertainty and provides employers with estimates of sampling and analytical error;

(5) Characterizes the sample material by identifying polymorphs of respirable crystalline silica present, identifies the presence of any interfering compounds that might affect the analysis, and makes any corrections necessary in order to obtain accurate sample analysis; and

(6) Analyzes quantitatively for crystalline silica only after confirming that the sample matrix is free of uncorrectable analytical interferences, corrects for analytical interferences, and uses a method that meets the following performance specifications:

(a) Each day that samples are analyzed, performs instrument calibration checks with standards that bracket the sample concentrations;

(b) Uses five or more calibration standard levels to prepare calibration curves and ensures that standards are distributed through the calibration range in a manner that accurately reflects the underlying calibration curve; and

(c) Optimizes methods and instruments to obtain a quantitative limit of detection that represents a value no higher than 25 percent of the PEL based on sample air volume.

AMENDATORY SECTION (Amending WSR 17-18-075, filed 9/5/17, effective 10/6/17)

WAC 296-841-20025 Permissible exposure limits (PELs).

IMPORTANT:

The following information applies to Table 3, Permissible Exposure Limits (PELs) for Airborne Contaminants.

(1) Ppm refers to parts of vapor or gas per million parts of air by volume, at 25 degrees C and 760 mm Hg pressure.

(2) Mg/m3 refers to milligrams of an airborne contaminant per cubic meter of air.

(3) F/cc refers to fibers per cubic centimeter of air.

(4) For a metal that is measured as the metal itself, only the CAS number for the metal is given. The CAS numbers for individual compounds of the metal are not provided. For more information about CAS registry numbers see the web site: http://www.cas.org.

(5) Short-term exposure limits (STEL) pertain to fifteen-minute exposure periods, unless another time period is noted in Table 3.

(6) An "X" in the "skin" column indicates the contaminant can be absorbed through the skin, either by airborne or direct contact.

(a) Personal protective equipment (PPE) to prevent skin contact may be needed to minimize the risk for adverse health effects when employees are exposed to these chemicals.

(b) Requirements for the use of gloves, coveralls, goggles, and other personal protective equipment can be found in WAC 296-800-160, Personal protective equipment (PPE).

(7) Nuisance dusts (also known as inert dusts) are included in the Table 3 listing, particulates not otherwise regulated (PNOR).

The PNOR listing in Table 3 also applies to other particulate airborne contaminants for which a specific PEL is NOT listed unless the airborne contaminant is found to require a lower limit.

(8) The respirable fraction of a particulate airborne contaminant is measured by sampling with a size-selector having the following characteristics:


Mean aerodynamic diameter in micrometers	Percent passing the selector
1	97
2	91
3	74
4	50
5	30
6	17
7	9
8	5
10	1

Table 3 "Permissible Exposure Limits (PELs) for Airborne Contaminants"


Airborne contaminant	CAS	TWA8	STEL	Ceiling	Skin
Abate (Temephos)	3383-96-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Acetaldehyde	75-07-0	100 ppm	150 ppm	——	——
Acetic acid	64-19-7	10 ppm	20 ppm	——	——
Acetic anhydride	108-24-7	——	——	5 ppm	——
Actinolite (asbestiform) (as asbestos) (see WAC 296-62-077 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Acetone	67-64-1	750 ppm	1,000 ppm	——	——
Acetonitrile	75-05-8	40 ppm	60 ppm	——	——
2-Acetylaminofluorene (see WAC 296-62-073)	53-96-3	——	——	——	——
Acetylene	74-86-2	Simple asphyxiant	——	——	——
Acetylene dichloride (1,2-Dichloroethylene)	540-59-0	200 ppm	250 ppm	——	——
Acetylene tetrabromide	79-27-6	1 ppm	3 ppm	——	——
Acetylsalicylic acid (Aspirin)	50-78-2	5 mg/m3	10 mg/m3	——	——
Acrolein	107-02-8	0.1 ppm	0.3 ppm	——	——
Acrylamide	79-06-1	0.03 mg/m3	0.09 mg/m3	——	X
Acrylic acid	79-10-7	10 ppm	20 ppm	——	X
Acrylonitrile (Vinyl cyanide) (see WAC 296-62-07336)	107-13-1	2 ppm	10 ppm	——	——
Aldrin	309-00-2	0.25 mg/m3	0.75 mg/m3	——	X
Allyl alcohol	107-18-6	2 ppm	4 ppm	——	X
Allyl chloride	107-05-1	1 ppm	2 ppm	——	——
Allyl glycidyl ether (AGE)	106-92-3	5 ppm	10 ppm	——	——
Allyl propyl disulfide	2179-59-1	2 ppm	3 ppm	——	——
alpha-Alumina (Aluminum oxide)	1344-28-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Aluminum (as Al)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pyro powders	——	5 mg/m3	10 mg/m3	——	——
Welding fumes	——	5 mg/m3	10 mg/m3	——	——
Soluble salts	——	2 mg/m3	4 mg/m3	——	——
Alkyls (NOC)	——	2 mg/m3	4 mg/m3	——	——
Aluminum oxide (Alundum, Corundum)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
4-Aminodiphenyl (see WAC 296-62-073)	92-67-1	——	——	——	——
2-Aminoethanol (Ethanolamine)	141-43-5	3 ppm	6 ppm	——	——
2-Aminopyridine	504-29-0	0.5 ppm	1.5 ppm	——	——
Amitrole	61-82-5	0.2 mg/m3	0.6 mg/m3	——	——
Ammonia	7664-41-7	25 ppm	35 ppm	——	——
Ammonium chloride, fume	12125-02-9	10 mg/m3	20 mg/m3	——	——
Ammonium sulfamate (Ammate)	7773-06-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5.0 mg/m3	10 mg/m3	——	——
Amosite (as asbestos) (see WAC 296-62-077 ((and)) and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
n-Amyl acetate	628-63-7	100 ppm	150 ppm	——	——
sec-Amyl acetate	626-38-0	125 ppm	156 ppm	——	——
Aniline and homologues	62-53-3	2 ppm	4 ppm	——	X
Anisidine (o, p-isomers)	29191-52-4	0.1 ppm	0.3 ppm	——	X
Anthophyllite (asbestiform) (as asbestos) (see WAC 296-62-077 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Antimony and compounds (as Sb)	7440-36-0	0.5 mg/m3	1.5 mg/m3	——	——
ANTU (alpha Naphthyl thiourea)	86-88-4	0.3 mg/m3	0.9 mg/m3	——	——
Argon	7440-37-1	Simple asphyxiant	——	——	——
Arsenic, organic compounds (as As)	7440-38-2	0.2 mg/m3	0.6 mg/m3	——	——
Arsenic, inorganic compounds (as As) (when use is covered by chapter 296-848 WAC)	7440-38-2	0.01 mg/m3	——	——	——
Arsenic, inorganic compounds (as As) (when use is not covered by chapter 296-848 WAC)	7440-38-2	0.2 mg/m3	0.6 mg/m3	——	——
Arsine	7784-42-1	0.05 ppm	0.15 ppm	——	——
Asbestos (see WAC 296-62-077 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Asphalt (Petroleum fumes)	8052-42-4	5 mg/m3	10 mg/m3	——	——
Atrazine	1912-24-9	5 mg/m3	10 mg/m3	——	——
Azinphos methyl (Guthion)	86-50-0	0.2 mg/m3	0.6 mg/m3	——	X
Azodrin (Monocrotophos)	6923-22-4	0.25 mg/m3	0.75 mg/m3	——	——
Barium, soluble compounds (as Ba)	7440-39-3	0.5 mg/m3	1.5 mg/m3	——	——
Barium sulfate	7727-43-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Baygon (Propoxur)	114-26-1	0.5 mg/m3	1.5 mg/m3	——	——
Benomyl	17804-35-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Benzene (see chapter 296-849 WAC)	71-43-2	1 ppm	5 ppm	——	——
Benzidine (see WAC 296-62-073)	92-87-5	——	——	——	——
p-Benzoquinone (Quinone)	106-51-4	0.1 ppm	0.3 ppm	——	——
Benzo(a) pyrene (Coal tar pitch volatiles)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Benzoyl peroxide	94-36-0	5 mg/m3	10 mg/m3	——	——
Benzyl chloride	100-44-7	1ppm	3 ppm	——	——
Beryllium and beryllium compounds (as Be)	7440-41-7	0.002 mg/m3	0.005 mg/m3 (30 min.)	0.025 mg/m3	——
Biphenyl (Diphenyl)	92-52-4	0.2 ppm	0.6 ppm	——	——
Bismuth telluride, undoped	1304-82-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Bismuth telluride, Se-doped	——	5 mg/m3	10 mg/m3	——	——
Borates, tetra, sodium salts	——	——	——	——	——
Anhydrous	1330-43-4	1 mg/m3	3 mg/m3	——	——
Decahydrate	1303-96-4	5 mg/m3	10 mg/m3	——	——
Pentahydrate	12179-04-3	1 mg/m3	3 mg/m3	——	——
Boron oxide	1303-86-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Boron tribromide	10294-33-4	——	——	1 ppm	——
Boron trifluoride	6737-07-2	——	——	1 ppm	——
Bromacil	314-40-9	1 ppm	3 ppm	——	——
Bromine	7726-95-6	0.1 ppm	0.3 ppm	——	——
Bromine pentafluoride	7789-30-2	0.1 ppm	0.3 ppm	——	——
Bromochloromethane (((Chlorobromomthane))) (Chlorobromomethane)	74-97-5	200 ppm	250 ppm	——	——
Bromoform	15-25-2	0.5 ppm	1.5 ppm	——	X
Butadiene (1,3-butadiene) (see WAC 296-62-07460)	106-99-0	1 ppm	5 ppm	——	——
Butane	106-97-8	800 ppm	1,000 ppm	——	——
Butanethiol (Butyl mercaptan)	109-79-5	0.5 ppm	1.5 ppm	——	——
2-Butanone (Methyl ethyl ketone)	78-93-3	200 ppm	300 ppm	——	——
2-Butoxy ethanol (Butyl cellosolve)	111-76-2	25 ppm	38 ppm	——	X
n-Butyl acetate	123-86-4	150 ppm	200 ppm	——	——
sec-Butyl acetate	105-46-4	200 ppm	250 ppm	——	——
tert-Butyl acetate	540-88-5	200 ppm	250 ppm	——	——
Butyl acrylate	141-32-2	10 ppm	20 ppm	——	——
n-Butyl alcohol	71-36-3	——	——	50 ppm	X
sec-Butyl alcohol	78-92-2	100 ppm	150 ppm	——	——
tert-Butyl alcohol	75-65-0	100 ppm	150 ppm	——	——
Butylamine	109-73-9	——	——	5 ppm	X
Butyl cellosolve (2-Butoxy ethanol)	111-76-2	25 ppm	38 ppm	——	——
tert-Butyl chromate (as Cr) (see WAC 296-62-08003)	1189-85-1	0.005 mg/m3	——	0.1 mg/m3	X
n-Butyl glycidyl ether (BGE)	2426-08-6	25 ppm	38 ppm	——	——
n-Butyl lactate	138-22-7	5 ppm	10 ppm	—-	——
Butyl mercaptan	109-79-5	0.5 ppm	1.5 ppm	——	——
o-sec-Butylphenol	89-72-5	5 ppm	10 ppm	——	X
p-tert-Butyl-toluene	98-51-1	10 ppm	20 ppm	——	——
Cadmium oxide fume (as Cd) (see WAC 296-62-074 and 296-155-174)	1306-19-0	0.005 mg/m3	——	——	——
Cadmium dust and salts (as Cd) (see WAC 296-62-074 and 296-155-174)	7440-43-9	0.005 mg/m3	——	——	——
Calcium arsenate (see chapter 296-848 WAC)	——	0.01 mg/m3	——	——	——
Calcium carbonate	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Calcium cyanamide	156-62-7	0.5 mg/m3	1.5 mg/m3	——	——
Calcium hydroxide	1305-62-0	5 mg/m3	10 mg/m3	——	——
Calcium oxide	1305-78-8	2 mg/m3	4 mg/m3	——	——
Calcium silicate	1344-95-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Calcium sulfate	7778-18-9	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Camphor (synthetic)	76-22-2	2 mg/m3	4 mg/m3	——	——
Caprolactam	105-60-2	——	——	——	——
Dust	——	1 mg/m3	3 mg/m3	——	——
Vapor	——	5 ppm	10 ppm	——	——
Captafol (Difolatan)	2425-06-1	0.1 mg/m3	0.3 mg/m3	——	X
Captan	133-06-2	5 mg/m3	10 mg/m3	——	——
Carbaryl (Sevin)	63-25-2	5 mg/m3	10 mg/m3	——	——
Carbofuran (Furadon)	1563-66-2	0.1 mg/m3	0.3 mg/m3	——	——
Carbon black	1333-86-4	3.5 mg/m3	7 mg/m3	——	——
Carbon dioxide	124-38-9	5,000 ppm	30,000 ppm	——	——
Carbon disulfide	75-15-0	4 ppm	12 ppm	——	X
Carbon monoxide	630-08-0	35 ppm	200 ppm (5 min.)	1,500 ppm	——
Carbon tetrabromide	558-13-4	0.1 ppm	0.3 ppm	——	——
Carbon tetrachloride (Tetrachloromethane)	56-23-5	2 ppm	4 ppm	——	X
Carbonyl chloride (Phosgene)	7803-51-2	0.1 ppm	0.3 ppm	——	——
Carbonyl fluoride	353-50-4	2 ppm	5 ppm	——	——
Catechol (Pyrocatechol)	120-80-9	5 ppm	10 ppm	——	X
Cellosolve acetate (2-Ethoxyethylacetate)	111-15-9	5 ppm	10 ppm	——	X
Cellulose (paper fiber)	9004-34-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Cesium hydroxide	21351-79-1	2 mg/m3	4 mg/m3	——	——
Chlordane	57-74-9	0.5 mg/m3	1.5 mg/m3	——	X
Chlorinated camphene (Toxaphen)	8001-35-2	0.5 mg/m3	1 mg/m3	——	X
Chlorinated diphenyl oxide	55720-99-5	0.5 mg/m3	1.5 mg/m3	——	——
Chlorine	7782-50-5	0.5 ppm	——	1 ppm	——
Chlorine dioxide	10049-04-4	0.1 ppm	0.3 ppm	——	——
Chlorine trifluoride	7790-91-2	——	——	0.1 ppm	——
Chloroacetaldehyde	107-20-0	——	——	1 ppm	——
a-Chloroacetophenone (Phenacyl chloride)	532-21-4	0.05 ppm	0.15 ppm	——	——
Chloroacetyl chloride	79-04-9	0.05 ppm	0.15 ppm	——	——
Chlorobenzene (Monochlorobenzene)	108-90-7	75 ppm	113 ppm	——	——
o-Chlorobenzylidene malononitrile (OCBM)	2698-41-1	——	——	0.05 ppm	X
Chlorobromomethane	74-97-5	200 ppm	250 ppm	——	——
2-Chloro-1, 3-butadiene (beta-Chloroprene)	126-99-8	10 ppm	20 ppm	——	X
Chlorodifluoromethane	75-45-6	1,000 ppm	1,250 ppm	——	——
Chlorodiphenyl (42% Chlorine) (PCB) (Polychlorobiphenyls)	53469-21-9	1 mg/m3	3 mg/m3	——	X
Chlorodiphenyl (54% Chlorine) (Polychlorobiphenyls (PCB))	11097-69-1	0.5 mg/m3	1.5 mg/m3	——	X
1-Chloro-2, 3-epoxypropane (Epichlorhydrin)	106-89-8	2 ppm	4 ppm	——	X
2-Chloroethanol (Ethylene chlorohydrin)	107-07-3	——	——	1 ppm	X
Chloroethylene (vinyl chloride) (See WAC 296-62-07329)	75-01-4	1 ppm	5 ppm	——	——
Chloroform (Trichloromethane)	67-66-3	2 ppm	4 ppm	——	——
1-Chloro-1-nitropropane	600-25-9	2 ppm	4 ppm	——	——
bis-Chloromethyl ether (see WAC 296-62-073)	542-88-1	——	——	——	——
Chloromethyl methyl ether (Methyl chloromethyl ether) (see WAC 296-62-073)	107-30-2	——	——	——	——
Chloropentafluoroethane	76-15-3	1,000 ppm	1,250 ppm	——	——
Chloropicrin (Nitrotrichloromethane)	76-06-2	0.1 ppm	0.3 ppm	——	——
beta-Chloroprene (2-Chloro-1, 3-butadiene)	126-99-8	10 ppm	20 ppm	——	X
o-Chlorostyrene	2039-87-4	50 ppm	75 ppm	——	——
o-Chlorotoluene	95-49-8	50 ppm	75 ppm	——	——
2-Chloro-6-trichloromethyl pyridine (Nitrapyrin)	1929-82-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Chlorpyrifos	2921-88-2	0.2 mg/m3	0.6 mg/m3	——	X
Chromic acid and chromates (as Cr) (when the compound is not covered by WAC 296-62-08003)	Varies with compound	——	——	0.1 mg/m3	——
Chromium	——	——	——	——	——
Chromium (VI) compounds (as Cr) (when the compound is covered by WAC 296-62-08003)	——	0.005 mg/m3	——	——	——
Chromium metal or Chromium (II) compounds Or Chromium (III) compounds	7440-47-3	0.5 mg/m3	——	——	——
Chromyl chloride (as Cr) (see WAC 296-62-08003)	14977-61-8	0.005 mg/m3	——	——	——
Chrysene (Coal tar pitch volatiles)	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Chrysotile (as asbestos) (see WAC 296-62-077 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Clopidol	2971-90-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Coal dust (less than 5% SiO2)	——	——	——	——	——
Respirable fraction	——	2 mg/m3	4 mg/m3	——	——
Coal dust (greater than or equal to 5% SiO2)	——	——	——	——	——
Respirable fraction	——	0.1 mg/m3	0.3 mg/m3	——	——
Coal tar pitch volatiles (benzene soluble fraction) Acridine Anthracene Benzo (a) pyrene Chrysene Phenanthrene Pyrene	65996-93-2	0.2 mg/m3	0.6 mg/m3	——	——
Cobalt, metal fume & dust (as Co)	7440-48-4	0.05 mg/m3	0.15 mg/m3	——	——
Cobalt carbonyl (as Co)	10210-68-1	0.1 mg/m3	0.3 mg/m3	——	——
Cobalt hydrocarbonyl (as Co)	16842-03-8	0.1 mg/m3	0.3 mg/m3	——	——
Coke oven emissions (see WAC 296-62-200)	——	0.15 mg/m3	——	——	——
Copper (as Cu)	7440-50-8	——	——	——	——
Fume	——	0.1 mg/m3	0.3 mg/m3	——	——
Dusts and mists	——	1 mg/m3	3 mg/m3	——	——
Cotton dust (raw) (waste sorting, blending, cleaning, willowing and garetting) (see WAC 296-62-14533)	——	1 mg/m3	——	——	——
Corundum (Aluminum oxide)	7429-90-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Crag herbicide (Sesone, Sodium-2, 4-dichloro-phenoxyethyl sulfate)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Cresol (all isomers)	1319-77-3	5 ppm	10 ppm	——	X
Crocidolite (as asbestos) (see WAC 296-62-077 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Crotonaldehyde	123-73-9; 4170-30-3	2 ppm	4 ppm	——	——
Crufomate	299-86-5	5 mg/m3	10 mg/m3	——	——
Cumene	98-82-8	50 ppm	75 ppm	——	X
Cyanamide	420-04-2	2 mg/m3	4 mg/m3	——	——
Cyanide (as CN)	Varies with compound	5 mg/m3	10 mg/m3	——	X
Cyanogen	460-19-5	10 ppm	20 ppm	——	——
Cyanogen chloride	506-77-4	——	——	0.3 ppm	——
Cyclohexane	110-82-7	300 ppm	375 ppm	——	——
Cyclohexanol	108-93-0	50 ppm	75 ppm	——	X
Cyclohexanone	108-94-1	25 ppm	38 ppm	——	X
Cyclohexene	110-83-8	300 ppm	375 ppm	——	——
Cyclohexylamine	108-91-8	10 ppm	20 ppm	——	——
Cyclonite (RDX)	121-82-4	1.5 mg/m3	3.0 mg/m3	——	X
Cyclopentadiene	542-92-7	75 ppm	113 ppm	——	——
Cyclopentane	287-92-3	600 ppm	750 ppm	——	——
Cyhexatin (Tricyclohexyltin hydroxide)	13121-70-5	5 mg/m3	10 mg/m3	——	——
2,4-D (Dichlorophenoxy- acetic acid)	94-75-7	10 mg/m3	20 mg/m3	——	——
DBCP (1,2-Dibromo-3- chloropropane) (See WAC 296-62-07342)	96-12-8	0.001 ppm	——	0.005 ppm	——
DDT (Dichlorodiphenyltri- chloroethane)	50-29-3	1 mg/m3	3 mg/m3	——	X
DDVP, (Dichlorvos)	62-73-7	0.1 ppm	0.3 ppm	——	X
Dasanit (Fensulfothion)	115-90-2	0.1 mg/m3	0.3 mg/m3	——	——
Decaborane	17702-41-9	0.05 ppm	0.15 ppm	——	X
Demeton	8065-48-3	0.01 ppm	0.03 ppm	——	X
Diacetone alcohol (4-hydroxy-4-methyl- 2-pentanone)	123-42-2	50 ppm	75 ppm	——	——
1, 2-Diaminoethane (Ethylenediamine)	107-15-3	10 ppm	20 ppm	——	——
Diazinon	333-41-5	0.1 mg/m3	0.3 mg/m3	——	X
Diazomethane	334-88-3	0.2 ppm	0.6 ppm	——	——
Diborane	19287-45-7	0.1 ppm	0.3 ppm	——	——
Dibrom (see Naled)	300-76-5	3 mg/m3	6 mg/m3	——	X
1, 2-Dibromo-3-chloropropane (DBCP) (see WAC 296-62-07342)	96-12-8	0.001 ppm	——	0.005 ppm	——
2-N-Dibutylamino ethanol	102-81-8	2 ppm	4 ppm	——	X
Dibutyl phosphate	107-66-4	1 ppm	2 ppm	——	——
Dibutyl phthalate	84-74-2	5 mg/m3	10 mg/m3	——	——
Dichloroacetylene	7572-29-4	——	——-	0.1 ppm	——
o-Dichlorobenzene	95-50-1	——	——	50 ppm	——
p-Dichlorobenzene	106-46-7	75 ppm	110 ppm	——	——
3, 3'-Dichlorobenzidine (see WAC 296-62-073)	91-94-1	——	——	——	——
Dichlorodiphenyltri- chloroethane (DDT)	50-29-3	1 mg/m3	3 mg/m3	——	X
Dichlorodifluoromethane	75-71-8	1,000 ppm	1,250 ppm	——	——
1, 3-Dichloro-5, 5-dimethyl hydantoin	118-52-5	0.2 mg/m3	0.4 mg/m3	——	——
1, 1-Dichloroethane (Ethylidine chloride)	75-34-3	100 ppm	150 ppm	——	——
1, 2-Dichloroethane (Ethylene dichloride)	107-06-2	1 ppm	2 ppm	——	——
1, 1-Dichloroethylene (Vinylidene chloride)	75-35-4	1 ppm	3 ppm	——	——
1, 2-Dichloroethylene (Acetylene dichloride)	540-59-0	200 ppm	250 ppm	——	——
Dichloroethyl ether	111-44-4	5 ppm	10 ppm	——	X
Dichlorofluoromethane	75-43-4	10 ppm	20 ppm	——	——
Dichloromethane (Methylene chloride) (See chapter 296-859 WAC)	75-09-2	25 ppm	125 ppm	——	——
1, 1-Dichloro-1-nitroethane	594-72-9	2 ppm	10 ppm	——	——
Dichlorophenoxyacetic acid (2, 4-D)	94-75-7	10 mg/m3	20 mg/m3	——	——
1, 2-Dichloropropane (Propylene dichloride)	78-87-5	75 ppm	110 ppm	——	——
Dichloropropene	542-75-6	1 ppm	3 ppm	——	X
2, 2-Dichloropropionic acid	75-99-0	1 ppm	3 ppm	——	——
Dichlorotetrafluoroethane	76-14-2	1,000 ppm	1,250 ppm	——	——
Dichlorvos (DDVP)	62-73-7	0.1 ppm	0.3 ppm	——	X
Dicrotophos	141-66-2	0.25 mg/m3	0.75 mg/m3	——	X
Dicyclopentadiene	77-73-6	5 ppm	10 ppm	——	——
Dicyclopentadienyl iron	102-54-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Dieldrin	60-57-1	0.25 mg/m3	0.75 mg/m3	——	X
Diethanolamine	111-42-2	3 ppm	6 ppm	——	——
Diethylamine	109-89-7	10 ppm	25 ppm	——	——
2-Diethylaminoethanol	100-37-8	10 ppm	20 ppm	——	X
Diethylene triamine	111-40-0	1 ppm	3 ppm	——	X
Diethyl ether (Ethyl ether)	60-29-7	400 ppm	500 ppm	——	——
Diethyl ketone	96-22-0	200 ppm	250 ppm	——	——
Diethyl phthalate	84-66-2	5 mg/m3	10 mg/m3	——	——
Difluorodibromomethane	75-61-6	100 ppm	150 ppm	——	——
Difolatan (Captafol)	2425-06-1	0.1 mg/m3	0.3 mg/m3	——	X
Diglycidyl ether (DGE)	2238-07-5	0.1 ppm	0.3 ppm	——	——
Dihydroxybenzene (Hydroquinone)	123-31-9	2 mg/m3	4 mg/m3	——	——
Diisobutyl ketone (2, 6- Dimethylheptanone)	108-83-8	25 ppm	38 ppm	——	——
Diisopropylamine	108-18-9	5 ppm	10 ppm	——	X
Dimethoxymethane (Methylal)	109-87-5	1,000 ppm	1,250 ppm	——	——
Dimethyl acetamide	127-19-5	10 ppm	20 ppm	——	X
Dimethylamine	124-40-3	10 ppm	20 ppm	——	——
4-Dimethylaminoazo benzene (see WAC 296-62-073)	60-11-7	——	——	——	——
Dimethylaminobenzene (Xylidene)	1300-73-8	2 ppm	4 ppm	——	X
Dimethylaniline (N, N-Dimethylaniline)	121-69-7	5 ppm	10 ppm	——	X
Dimethylbenzene (Xylene)	1300-73-8	100 ppm	150 ppm	——	——
Dimethyl-1, 2-dibromo-2, 2-dichloroethyl phosphate (Naled)	300-76-5	3 mg/m3	6 mg/m3	——	X
Dimethylformamide	68-12-2	10 ppm	20 ppm	——	X
2, 6-Dimethylheptanone (Diisobutyl ketone)	108-83-8	25 ppm	38 ppm	——	——
1, 1-Dimethylhydrazine	57-14-7	0.5 ppm	1.5 ppm	——	X
Dimethyl phthalate	131-11-3	5 mg/m3	10 mg/m3	——	——
Dimethyl sulfate	77-78-1	0.1 ppm	0.3 ppm	——	X
Dinitolmide (3, 5-Dinitro-o-toluamide)	148-01-6	5 mg/m3	10 mg/m3	——	——
Dinitrobenzene (all isomers - alpha, meta and para)	528-29-0; 99-65-0; 100-25-4	0.15 ppm	0.45 ppm	——	X
Dinitro-o-cresol	534-52-1	0.2 mg/m3	0.6 mg/m3	——	X
3, 5-Dinitro-o-toluamide (Dinitolmide)	148-01-6	5 mg/m3	10 mg/m3	——	——
Dinitrotoluene	25321-14-6	1.5 mg/m3	3 mg/m3	——	X
Dioxane (Diethylene dioxide)	123-91-1	25 ppm	38 ppm	——	X
Dioxathion	78-34-2	0.2 mg/m3	0.6 mg/m3	——	X
Diphenyl (Biphenyl)	92-52-4	0.2 ppm	0.6 ppm	——	——
Diphenylamine	122-39-4	10 mg/m3	20 mg/m3	——	——
Diphenylmethane diisocyanate (Methylene bisphenyl isocyanate (MDI))	101-68-8	——	——	0.02 ppm	——
Dipropylene glycol methyl ether	34590-94-8	100 ppm	150 ppm	——	X
Dipropyl ketone	123-19-3	50 ppm	75 ppm	——	——
Diquat	85-00-7	0.5 mg/m3	1.5 mg/m3	——	——
Di-sec, Octyl phthalate (Di-2-ethylhexylphthalate)	117-81-7	5 mg/m3	10 mg/m3	——	——
Disulfram	97-77-8	2 mg/m3	4 mg/m3	——	——
Disulfoton	298-04-4	0.1 mg/m3	0.3 mg/m3	——	X
2, 6-Di-tert-butyl-p-cresol	128-37-0	10 mg/m3	20 mg/m3	——	——
Diuron	330-54-1	10 mg/m3	20 mg/m3	——	——
Divinyl benzene	1321-74-0	10 ppm	20 ppm	——	——
Emery	12415-34-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Endosulfan (Thiodan)	115-29-7	0.1 mg/m3	0.3 mg/m3	——	X
Endrin	72-20-8	0.1 mg/m3	0.3 mg/m3	——	X
Epichlorhydrin (1-Chloro-2, 3-epoxypropane)	106-89-8	2 ppm	4 ppm	——	X
EPN	2104-64-5	0.5 mg/m3	1.5 mg/m3	——	X
1, 2-Epoxypropane (Propylene oxide)	75-56-9	20 ppm	30 ppm	——	——
2, 3-Epoxy-1-propanol (Glycidol)	556-52-5	25 ppm	38 ppm	——	——
Ethane	——	Simple asphyxiant	——	——	——
Ethanethiol (Ethyl mercaptan)	75-08-1	0.5 ppm	1.5 ppm	——	——
Ethanol (Ethyl alcohol)	64-17-5	1,000 ppm	1,250 ppm	——	——
Ethanolamine (2-Aminoethanol)	141-43-5	3 ppm	6 ppm	——	——
Ethion	563-12-2	0.4 mg/m3	1.2 mg/m3	——	X
2-Ethoxyethanol (Glycol monoethyl ether)	110-80-5	5 ppm	10 ppm	——	X
2-Ethoxyethyl acetate (Cellosolve acetate)	111-15-9	5 ppm	10 ppm	——	X
Ethyl acetate	141-78-6	400 ppm	500 ppm	——	——
Ethyl acrylate	140-88-5	5 ppm	25 ppm	——	X
Ethyl alcohol (ethanol)	64-17-5	1,000 ppm	1,250 ppm	——	——
Ethylamine	75-04-07	10 ppm	20 ppm	——	——
Ethyl amyl ketone (5-Methyl-3-hepatone)	541-85-5	25 ppm	38 ppm	——	——
Ethyl benzene	100-41-4	100 ppm	125 ppm	——	——
Ethyl bromide	74-96-4	200 ppm	250 ppm	——	——
Ethyl butyl ketone (3-Heptanone)	106-35-4	50 ppm	75 ppm	——	——
Ethyl chloride	75-00-3	1,000 ppm	1,250 ppm	——	——
Ethylene	74-85-1	Simple asphyxiant	——	——	——
Ethylene chlorohydrin (2-Chloroethanol)	107-07-3	——	——	1 ppm	X
Ethylenediamine (1,2- Diaminoethane)	107-15-3	10 ppm	20 ppm	——	X
Ethylene dibromide	106-93-4	0.1 ppm	0.5 ppm	——	——
Ethylene dichloride (1,2-Dichloroethane)	107-06-2	1 ppm	2 ppm	——	——
Ethylene glycol	107-21-1	——	——	50 ppm	——
Ethylene glycol dinitrate	628-96-6	——	0.1 mg/m3	——	X
Ethylene glycol monomethyl ether acetate (Methyl cellosolve acetate)	——	5 ppm	10 ppm	——	X
Ethyleneimine (see WAC 296-62-073)	151-56-4	——	——	——	X
Ethylene oxide (see chapter 296-855 WAC)	75-21-8	1 ppm	5 ppm	——	——
Ethyl ether (Diethyl ether)	60-29-7	400 ppm	500 ppm	——	——
Ethyl formate	109-94-4	100 ppm	125 ppm	——	——
Ethylidine chloride (1, 1-Dichloroethane)	107-06-2	1 ppm	2 ppm	——	——
Ethylidene norbornene	16219-75-3	——	——	5.0 ppm	——
Ethyl mercaptan (Ethanethiol)	75-08-1	0.5 ppm	1.5 ppm	——	——
n-Ethylmorpholine	100-74-3	5 ppm	10 ppm	——	X
Ethyl sec-amyl ketone (5-methyl-3-heptanone)	541-85-5	25 ppm	38 ppm	——	——
Ethyl silicate	78-10-4	10 ppm	20 ppm	——	——
Fenamiphos	22224-92-6	0.1 mg/m3	0.3 mg/m3	——	X
Fensulfothion (Dasanit)	115-90-2	0.1 mg/m3	0.3 mg/m3	——	——
Fenthion	55-38-9	0.2 mg/m3	0.6 mg/m3	——	X
Ferbam	——	——	——	——	——
Total particulate	14484-64-1	10 mg/m3	20 mg/m3	——	——
Ferrovanadium dust	12604-58-9	1 mg/m3	3 mg/m3	——	——
Fluorides (as F)	Varies with compound	2.5 mg/m3	5 mg/m3	——	——
Fluorine	7782-41-4	0.1 ppm	0.3 ppm	——	——
Fluorotrichloromethane (see Trichlorofluoro methane)	75-69-4	——	——	1,000 ppm	——
Fonofos	944-22-9	0.1 mg/m3	0.3 mg/m3	——	X
Formaldehyde (see chapter 296-856 WAC)	50-00-0	0.75 ppm	2 ppm	——	——
Formamide	75-12-7	20 ppm	30 ppm	——	——
Formic acid	64-18-6	5 ppm	10 ppm	——	——
Furadon (carbofuran)	1563-66-2	0.1 mg/m3	0.3 mg/m3	——	——
Furfural	98-01-1	2 ppm	4 ppm	——	X
Furfuryl alcohol	98-00-0	10 ppm	15 ppm	——	X
Gasoline	8006-61-9	300 ppm	500 ppm	——	——
Germanium tetrahydride	7782-65-2	0.2 ppm	0.6 ppm	——	——
Glass, fibrous or dust	——	10 mg/m3	20 mg/m3	——	——
Glutaraldehyde	111-30-8	——	——	0.2 ppm	——
Glycerin mist	56-81-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Glycidol (2, 3-Epoxy-1-propanol)	556-52-5	25 ppm	38 ppm	——	——
Glycol monoethyl ether (2-Ethoxyethanol)	110-80-5	5 ppm	10 ppm	——	X
Grain dust (oat, wheat, barley)	——	10 mg/m3	20 mg/m3	——	——
Graphite, natural	7782-42-5	——	——	——	——
Respirable particulate	——	2.5 mg/m3	5 mg/m3	——	——
Graphite, synthetic	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Guthion (Azinphosmethyl)	86-50-0	0.2 mg/m3	0.6 mg/m3	——	X
Gypsum	13397-24-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Hafnium	7440-58-6	0.5 mg/m3	1.5 mg/m3	——	——
Helium	——	Simple asphyxiant	——	——	——
Heptachlor	76-44-8	0.5 mg/m3	1.5 mg/m3	——	X
Heptane (n-heptane)	142-82-5	400 ppm	500 ppm	——	——
2-Heptanone (Methyl n-amyl ketone)	110-43-0	50 ppm	75 ppm	——	——
3-Heptanone (Ethyl butyl ketone)	106-35-4	50 ppm	75 ppm	——	——
Hexachlorobutadiene	87-68-3	0.02 ppm	0.06 ppm	——	X
Hexachlorocyclopentadiene	77-47-4	0.01 ppm	0.03 ppm	——	——
Hexachloroethane	67-72-1	1 ppm	3 ppm	——	X
Hexachloronaphthalene	1335-87-1	0.2 mg/m3	0.6 mg/m3	——	X
Hexafluoroacetone	684-16-2	0.1 ppm	0.3 ppm	——	X
Hexane	——	——	——	——	——
n-hexane	110-54-3	50 ppm	75 ppm	——	——
other isomers	Varies with compound	500 ppm	1,000 ppm	——	——
2-Hexanone (Methyl-n-butyl ketone)	591-78-6	5 ppm	10 ppm	——	——
Hexone (Methyl isobutyl ketone)	108-10-1	50 ppm	75 ppm	——	——
sec-Hexyl acetate	108-84-9	50 ppm	75 ppm	——	——
Hexylene glycol	107-41-5	——	——	25 ppm	——
Hydrazine	302-01-2	0.1 ppm	0.3 ppm	——	X
Hydrogen	——	Simple asphyxiant	——	——	——
Hydrogenated terphenyls	61788-32-7	0.5 ppm	1.5 ppm	——	——
Hydrogen bromide	10035-10-6	——	——	3.0 ppm	——
Hydrogen chloride	7647-01-0	——	——	5.0 ppm	——
Hydrogen cyanide	74-90-8	——	4.7 ppm	——	X
Hydrogen fluoride	7664-39-3	——	——	3 ppm	——
Hydrogen peroxide	7722-84-1	1 ppm	3 ppm	——	——
Hydrogen selenide (as Se)	7783-07-5	0.05 ppm	0.15 ppm	——	——
Hydrogen sulfide	7783-06-4	10 ppm	15 ppm	——	——
Hydroquinone (Dihydroxybenzene)	123-31-9	2 mg/m3	4 mg/m3	——	——
4-Hydroxy-4-methyl-2-pentanone (Diacetone alcohol)	123-42-2	50 ppm	75 ppm	——	——
2-Hydroxypropyl acrylate	99-61-1	0.5 ppm	1.5 ppm	——	X
Indene	95-13-6	10 ppm	20 ppm	——	——
Indium and compounds (as In)	7440-74-6	0.1 mg/m3	0.3 mg/m3	——	——
Iodine	7553-56-2	——	——	0.1 ppm	——
Iodoform	75-47-8	0.6 ppm	1.8 ppm	——	——
Iron oxide dust and fume (as Fe)	1309-37-1	——	——	——	——
Total particulate	——	5 mg/m3	10 mg/m3	——	——
Iron pentacarbonyl (as Fe)	13463-40-6	0.1 ppm	0.2 ppm	——	——
Iron salts, soluble (as Fe)	Varies with compound	1 mg/m3	3 mg/m3	——	——
Isoamyl acetate	123-92-2	100 ppm	150 ppm	——	——
Isoamyl alcohol (primary and secondary)	123-51-3	100 ppm	125 ppm	——	——
Isobutyl acetate	110-19-0	150 ppm	188 ppm	——	——
Isobutyl alcohol	78-83-1	50 ppm	75 ppm	——	——
Isooctyl alcohol	26952-21-6	50 ppm	75 ppm	——	X
Isophorone	78-59-1	4 ppm	——	5 ppm	——
Isophorone diisocyanate	4098-71-9	0.005 ppm	0.02 ppm	——	X
Isopropoxyethanol	109-59-1	25 ppm	38 ppm	——	——
Isopropyl acetate	108-21-4	250 ppm	310 ppm	——	——
Isopropyl alcohol	67-63-0	400 ppm	500 ppm	——	——
Isopropylamine	75-31-0	5 ppm	10 ppm	——	——
N-Isopropylaniline	768-52-5	2 ppm	4 ppm	——	X
Isopropyl ether	108-20-3	250 ppm	313 ppm	——	——
Isopropyl glycidyl ether (IGE)	4016-14-2	50 ppm	75 ppm	——-	——
Kaolin	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Ketene	463-51-4	0.5 mg/m3	1.5 mg/m3	——	——
Lannate (Methomyl)	16752-77-5	2.5 mg/m3	5 mg/m3	——	——
Lead, inorganic (as Pb) (see WAC 296-62-07521 and 296-155-176)	7439-92-1	0.05 mg/m3	——	——	——
Lead arsenate (as Pb) (see WAC 296-62-07521, 296-155-176, and chapter 296-848 WAC)	3687-31-8	0.05 mg/m3	——	——	——
Lead chromate (as Pb) (see WAC 296-62-08003, 296-62-07521, and 296-155-176)	7758-97-6	0.05 mg/m3	——	——	——
Limestone	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Lindane	58-89-9	0.5 mg/m3	1.5 mg/m3	——	X
Lithium hydride	7580-67-8	0.025 mg/m3	0.075 mg/m3	——	——
L.P.G. (liquified petroleum gas)	68476-85-7	1,000 ppm	1,250 ppm	——	——
Magnesite	546-93-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Magnesium oxide fume	1309-48-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Malathion	121-75-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	X
Maleic anhydride	108-31-6	0.25 ppm	0.75 ppm	——	——
Manganese and compounds (as Mn)	7439-96-5	——	——	5 mg/m3	——
Manganese cyclopentadienyl tricarbonyl (as Mn)	12079-65-1	0.1 mg/m3	0.3 mg/m3	——	X
Manganese tetroxide and fume (as Mn)	7439-96-5	1 mg/m3	3 mg/m3	——	——
Marble	1317-65-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
MBOCA (4, 4'-Methylene bis (2-chloro-aniline)) (see WAC 296-62-073)	101-14-4	——	——	——	X
MDA (4, 4-Methylene dianiline) (see WAC 296-62-076 and 296-155-173)	101-77-9	0.01 ppm	0.1 ppm	——	X
MDI (Methylene bisphenyl isocyanate) (Diphenylmethane diisocyanate)	101-68-8	——	——	0.02 ppm	——
MEK (Methyl ethyl ketone) (2-Butanone)	78-93-3	200 ppm	300 ppm	——	——
MEKP (Methyl ethyl ketone peroxide)	1338-23-4	——	——	0.2 ppm	——
Mercury (as Hg)	7439-97-6	——	——	——	——
Aryl and inorganic	——	0.1 mg/m3	0.3 mg/m3	——	X
Organo-alkyl compounds	——	0.01 mg/m3	0.03 mg/m3	——	X
Vapor	——	0.05 mg/m3	0.15 mg/m3	——	X
Mesityl oxide	141-79-7	15 ppm	25 ppm	——	——
Methacrylic acid	79-41-4	20 ppm	30 ppm	——	X
Methane	——	Simple asphyxiant	——	——	——
Methanethiol (Methyl mercaptan)	74-93-1	0.5 ppm	1.5 ppm	——	——
Methanol (Methyl alcohol)	67-56-1	200 ppm	250 ppm	——	X
Methomyl (lannate)	16752-77-5	2.5 mg/m3	5 mg/m3	——	——
Methoxychlor	72-43-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
2-Methoxyethanol (Methyl cellosolve)	109-86-4	5 ppm	10 ppm	——	X
2-Methoxyethyl acetate (Methyl cellosolve acetate)	110-49-6	5 ppm	10 ppm	——	X
4-Methoxyphenol	150-76-5	5 mg/m3	10 mg/m3	——	——
Methyl acetate	79-20-9	200 ppm	250 ppm	——	——
Methyl acetylene (propyne)	74-99-7	1,000 ppm	1,250 ppm	——	——
Methyl acetylene-propadiene mixture (MAPP)	——	1,000 ppm	1,250 ppm	——	——
Methyl acrylate	96-33-3	10 ppm	20 ppm	——	X
Methylacrylonitrile	126-98-7	1 ppm	3 ppm	——	X
Methylal (Dimethoxy-methane)	109-87-5	1,000 ppm	1,250 ppm	——	——
Methyl alcohol (methanol)	67-56-1	200 ppm	250 ppm	——	X
Methylamine	74-89-5	10 ppm	20 ppm	——	——
Methyl amyl alcohol (Methyl isobutyl carbinol)	108-11-2	25 ppm	40 ppm	——	X
Methyl n-amyl ketone (2-Heptanone)	110-43-0	50 ppm	75 ppm	——	——
N-Methyl aniline (Monomethyl aniline)	100-61-8	0.5 ppm	1.5 ppm	——	X
Methyl bromide	74-83-9	5 ppm	10 ppm	——	X
Methyl-n-butyl ketone (2-Hexanone)	591-78-6	5 ppm	10 ppm	——	——
Methyl cellosolve (2-Methoxyethanol)	109-86-4	5 ppm	10 ppm	——	X
Methyl cellosolve acetate (2-Methoxyethyl acetate)	110-49-6	5 ppm	10 ppm	——	X
Methyl chloride	74-87-3	50 ppm	100 ppm	——	——
Methyl chloroform (1, 1, 1-trichlorethane)	71-55-6	350 ppm	450 ppm	——	——
Methyl chloromethyl ether (chloromethyl methyl ether) (see WAC 296-62-073)	107-30-2	——	——	——	——
Methyl 2-cyanoacrylate	137-05-3	2 ppm	4 ppm	——	——
Methylcyclohexane	108-87-2	400 ppm	500 ppm	——	——
Methylcyclohexanol	25639-42-3	50 ppm	75 ppm	——	——
Methylcyclohexanone	583-60-8	50 ppm	75 ppm	——	X
Methylcyclopentadienyl manganese tricarbonyl (as Mn)	12108-13-3	0.2 mg/m3	0.6 mg/m3	——	X
Methyl demeton	8022-00-2	0.5 mg/m3	1.5 mg/m3	——	X
Methylene bisphenyl isocyanate (MDI) (Diphenylmethane diisocyanate)	101-68-8	——	——	0.02 ppm	——
4, 4'-Methylene bis (2-chloro-aniline) (MBOCA) (see WAC 296-62-073)	101-14-4	——	——	——	X
Methylene bis (4-cyclohexylisocyanate)	5124-30-1	——	——	0.01 ppm	——
Methylene chloride (Dichloromethane) (see chapter 296-859 WAC)	75-09-2	25 ppm	125 ppm	——	——
4, 4-Methylene dianiline (MDA) (see WAC 296-62-076 and 296-155-173)	101-77-9	0.01 ppm	0.1 ppm	——	X
Methyl ethyl ketone (MEK) (2-Butanone)	78-93-3	200 ppm	300 ppm	——	——
Methyl ethyl ketone peroxide (MEKP)	1338-23-4	——	——	0.2 ppm	——
Methyl formate	107-31-3	100 ppm	150 ppm	——	——
5-Methyl-3-heptanone (Ethyl amyl ketone)	541-85-5	25 ppm	38 ppm	——	——
Methyl hydrazine (Monomethyl hydrazine)	60-34-4	——	——	0.2 ppm	X
Methyl iodide	74-88-4	2 ppm	4 ppm	——	X
Methyl isoamyl ketone	110-12-3	50 ppm	75 ppm	——	——
Methyl isobutyl carbinol (Methyl amyl alcohol)	108-11-2	25 ppm	40 ppm	——	X
Methyl isobutyl ketone (Hexone)	108-10-1	50 ppm	75 ppm	——	——
Methyl isocyanate	624-83-9	0.02 ppm	0.06 ppm	——	X
Methyl isopropyl ketone	563-80-4	200 ppm	250 ppm	——	——
Methyl mercaptan (Methanethiol)	74-93-1	0.5 ppm	1.5 ppm	——	——
Methyl methacrylate	80-62-6	100 ppm	150 ppm	——	——
Methyl parathion	298-00-0	0.2 mg/m3	0.6 mg/m3	——	X
Methyl propyl ketone (2-Pentanone)	107-87-9	200 ppm	250 ppm	——	——
Methyl silicate	684-84-5	1 ppm	3 ppm	——	——
alpha-Methyl styrene	98-83-9	50 ppm	100 ppm	——	——
Mevinphos (Phosdrin)	7786-34-7	0.01 ppm	0.03 ppm	——	X
Metribuzin	21087-64-9	5 mg/m3	10 mg/m3	——	——
Mica (Silicates) Respirable fraction	12001-26-2	3 mg/m3	6 mg/m3	——	——
Molybdenum (as Mo)	7439-98-7	——	——	——	——
Soluble compounds	——	5 mg/m3	10 mg/m3	——	——
Insoluble compounds	——	10 mg/m3	20 mg/m3	——	——
Monochlorobenzene (Chlorobenzene)	108-90-7	75 ppm	113 ppm	——	——
Monocrotophos (Azodrin)	6923-22-4	0.25 mg/m3	0.75 mg/m3	——	——
Monomethyl aniline (N-Methyl aniline)	100-61-8	0.5 ppm	1.5 ppm	——	X
Monomethyl hydrazine	——	——	——	0.2 ppm	——
Morpholine	110-91-8	20 ppm	30 ppm	——	X
Naled (Dibrom)	300-76-5	3 mg/m3	6 mg/m3	——	X
Naphtha	8030-30-6	100 ppm	150 ppm	——	X
Naphthalene	91-20-3	10 ppm	15 ppm	——	——
alpha-Naphthylamine (see WAC 296-62-073)	134-32-7	——	——	——	——
beta-Naphthylamine (see WAC 296-62-073)	91-59-8	——	——	——	——
Neon	7440-01-9	Simple asphyxiant	——	——	——
Nickel carbonyl (as Ni)	13463-39-3	0.001 ppm	0.003 ppm	——	——
Nickel (as Ni)	7440-02-0	——	——	——	——
Metal and insoluble compounds	——	1 mg/m3	3 mg/m3	——	——
Soluble compounds	——	0.1 mg/m3	0.3 mg/m3	——	——
Nicotine	54-11-5	0.5 mg/m3	1.5 mg/m3	——	X
Nitrapyrin (2-Chloro-6 trichloromethyl pyridine)	1929-82-4	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Nitric acid	7697-37-2	2 ppm	4 ppm	——	——
Nitric oxide	10102-43-9	25 ppm	38 ppm	——	——
p-Nitroaniline	100-01-6	3 mg/m3	6 mg/m3	——	X
Nitrobenzene	98-95-3	1 ppm	3 ppm	——	X
4-Nitrobiphenyl (see WAC 296-62-073)	92-93-3	——	——	——	——
p-Nitrochlorobenzene	100-00-5	0.5 mg/m3	1.5 mg/m3	——	X
4-Nitrodiphenyl (see WAC 296-62-073)	——	——	——	——	——
Nitroethane	79-24-3	100 ppm	150 ppm	——	——
Nitrogen	7727-37-9	Simple asphyxiant	——	——	——
Nitrogen dioxide	10102-44-0	——	1 ppm	——	——
Nitrogen oxide (Nitrous oxide)	10024-97-2	50 ppm	75 ppm	——	——
Nitrogen trifluoride	7783-54-2	10 ppm	20 ppm	——	——
Nitroglycerin	55-63-0	——	0.1 mg/m3	——	X
Nitromethane	75-52-5	100 ppm	150 ppm	——	——
1-Nitropropane	108-03-2	25 ppm	38 ppm	——	——
2-Nitropropane	79-46-9	10 ppm	20 ppm	——	——
N-Nitrosodimethylamine (see WAC 296-62-073)	62-75-9	——	——	——	——
Nitrotoluene	——	——	——	——	——
o-isomer	88-72-2	2 ppm	4 ppm	——	X
m-isomer	98-08-2	2 ppm	4 ppm	——	X
p-isomer	99-99-0	2 ppm	4 ppm	——	X
Nitrotrichloromethane (Chloropicrin)	76-06-2	0.1 ppm	0.3 ppm	——	——
Nitrous oxide (Nitrogen oxide)	10024-97-2	50 ppm	75 ppm	——	——
Nonane	111-84-2	200 ppm	250 ppm	——	——
Nuisance dusts (see Particulates not otherwise regulated)	——	——	——	——	——
Octachloronaphthalene	2234-13-1	0.1 mg/m3	0.3 mg/m3	——	X
Octane	111-65-9	300 ppm	375 ppm	——	——
Oil mist mineral (particulate)	8012-95-1	5 mg/m3	10 mg/m3	——	——
Osmium tetroxide (as Os)	20816-12-0	0.0002 ppm	0.0006 ppm	——	——
Oxalic acid	144-62-7	1 mg/m3	2 mg/m3	——	——
Oxygen See requirements in other chapters such as: Chapter 296-809 WAC, Confined spaces; chapter 296-843 WAC, Hazardous waste operations; chapter 296-824 WAC, Emergency response; WAC 296-62-100, Oxygen deficient atmospheres	——	——	——	——	——
Oxygen difluoride	7783-41-7	——	——	0.05 ppm	——
Ozone	10028-15-6	0.1 ppm	0.3 ppm	——	——
Paper fiber (Cellulose)	9004-34-6	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Paraffin wax fume	8002-74-2	2 mg/m3	4 mg/m3	——	——
Paraquat	——	——	——	——	——
Respirable fraction	4685-14-7	0.1 mg/m3	0.3 mg/m3	——	X
	1910-42-5
	2074-50-2
Parathion	56-38-2	0.1 mg/m3	0.3 mg/m3	——	X
Particulate polycyclic aromatic hydrocarbons (see coal tar pitch volatiles)				——	——
Particulates not otherwise regulated	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pentaborane	19624-22-7	0.005 ppm	0.015 ppm	——	——
Pentachloronaphthalene	1321-64-8	0.5 mg/m3	1.5 mg/m3	——	X
Pentachlorophenol	87-86-5	0.5 mg/m3	1.5 mg/m3	——	X
Pentaerythritol	115-77-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Pentane	109-66-0	600 ppm	750 ppm	——	——
2-Pentanone (methyl propyl ketone)	107-87-9	200 ppm	250 ppm	——	——
Perchloroethylene (tetrachloroethylene)	127-18-4	25 ppm	38 ppm	——	——
Perchloromethyl mercaptan	594-42-3	0.1 ppm	0.3 ppm	——	——
Perchloryl fluoride	7616-94-6	3 ppm	6 ppm	——	——
Perlite	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Petroleum distillates (Naptha, rubber solvent)	——	100 ppm	150 ppm	——	——
Phenacyl chloride (a-Chloroacetophenone)	532-21-4	0.05 ppm	0.15 ppm	——	——
Phenol	108-95-2	5 ppm	10 ppm	——	X
Phenothiazine	92-84-2	5 mg/m3	10 mg/m3	——	X
p-Phenylene diamine	106-50-3	0.1 mg/m3	0.3 mg/m3	——	X
Phenyl ether (vapor)	101-84-8	1 ppm	3 ppm	——	——
Phenyl ether-diphenyl mixture (vapor)	——	1 ppm	3 ppm	——	——
Phenylethylene (Styrene)	100-42-5	50 ppm	100 ppm	——	——
Phenyl glycidyl ether (PGE)	122-60-1	1 ppm	3 ppm	——	——
Phenylhydrazine	100-63-0	5 ppm	10 ppm	——	X
Phenyl mercaptan	108-98-5	0.5 ppm	1.5 ppm	——	——
Phenylphosphine	638-21-1	——	——	0.05 ppm	——
Phorate	298-02-2	0.05 mg/m3	0.2 mg/m3	——	X
Phosdrin (Mevinphos)	7786-34-7	0.01 ppm	0.03 ppm	——	X
Phosgene (carbonyl chloride)	75-44-5	0.1 ppm	0.3 ppm	——	——
Phosphine	7803-51-2	0.3 ppm	1 ppm	——	——
Phosphoric acid	7664-38-2	1 mg/m3	3 mg/m3	——	——
Phosphorus (yellow)	7723-14-0	0.1 mg/m3	0.3 mg/m3	——	——
Phosphorous oxychloride	10025-87-3	0.1 ppm	0.3 ppm	——	——
Phosphorus pentachloride	10026-13-8	0.1 ppm	0.3 ppm	——	——
Phosphorus pentasulfide	1314-80-3	1 mg/m3	3 mg/m3	——	——
Phosphorus trichloride	12-2-19	0.2 ppm	0.5 ppm	——	——
Phthalic anhydride	85-44-9	1 ppm	3 ppm	——	——
m-Phthalodinitrile	626-17-5	5 mg/m3	10 mg/m3	——	——
Picloram	1918-02-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Picric acid (2, 4, 6- Trinitrophenol)	88-89-1	0.1 mg/m3	0.3 mg/m3	——	X
Pindone (2-Pivalyl-1, 3-indandione, Pival)	83-26-1	0.1 mg/m3	0.3 mg/m3	——	——
Piperazine dihydrochloride	142-64-3	5 mg/m3	10 mg/m3	——	——
Pival (Pindone)	83-26-1	0.1 mg/m3	0.3 mg/m3	——	——
Plaster of Paris	26499-65-0	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Platinum (as Pt)	7440-06-4	——	——	——	——
Metal	——	1 mg/m3	3 mg/m3	——	——
Soluble salts	——	0.002 mg/m3	0.006 mg/m3	——	——
Polychlorobiphenyls (Chlorodiphenyls)	——	——	——	——	——
42% Chlorine (PCB)	53469-21-9	1 mg/m3	3 mg/m3	——	X
54% Chlorine (PCB)	11097-69-1	0.5 mg/m3	1.5 mg/m3	——	X
Portland cement	65997-15-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Potassium hydroxide	1310-58-3	——	——	2 mg/m3	——
Propane	74-98-6	1,000 ppm	1,250 ppm	——	——
Propargyl alcohol	107-19-7	1 ppm	3 ppm	——	X
beta-Propiolactone (see WAC 296-62-073)	57-57-8	——	——	——	——
Propionic acid	79-09-4	10 ppm	20 ppm	——	——
Propoxur (Baygon)	114-26-1	0.5 mg/m3	1.5 mg/m3	——	——
n-Propyl acetate	109-60-4	200 ppm	250 ppm	——	——
n-Propyl alcohol	71-23-8	200 ppm	250 ppm	——	X
n-Propyl nitrate	627-13-4	25 ppm	40 ppm	——	——
Propylene	——	Simple asphyxiant	——	——	——
Propylene dichloride (1, 2-Dichloropropane)	78-87-5	75 ppm	110 ppm	——	——
Propylene glycol dinitrate	6423-43-4	0.05 ppm	0.15 ppm	——	X
Propylene glycol monomethyl ether	107-98-2	100 ppm	150 ppm	——	——
Propylene imine	75-55-8	2 ppm	4 ppm	——	X
Propylene oxide (1,2- Epoxypropane)	75-56-9	20 ppm	30 ppm	——	——
Propyne (Methyl acetylene)	74-99-7	1,000 ppm	1,250 ppm	——	——
Pyrethrum	8003-34-7	5 mg/m3	10 mg/m3	——	——
Pyridine	110-86-1	5 ppm	10 ppm	——	——
Pyrocatachol (Catechol)	120-80-9	5 ppm	10 ppm	——	X
Quinone (p-Benzoquinone)	106-51-4	0.1 ppm	0.3 ppm	——	——
RDX (Cyclonite)	——	1.5 mg/m3	3 mg/m3	——	X
Resorcinol	108-46-3	10 ppm	20 ppm	——	——
Rhodium (as Rh)	7440-16-6	——	——	——	——
Insoluble compounds, metal fumes and dusts	——	0.1 mg/m3	0.3 mg/m3	——	——
Soluble compounds, salts	——	0.001 mg/m3	0.003 mg/m3	——	——
Ronnel	299-84-3	10 mg/m3	20 mg/m3	——	——
Rosin core solder, pyrolysis products (as formaldehyde)	8050-09-7	0.1 mg/m3	0.3 mg/m3	——	——
Rotenone	83-79-4	5 mg/m3	10 mg/m3	——	——
Rouge	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Rubber solvent (naphtha)	8030-30-6	100 ppm	150 ppm	——	——
Selenium compounds (as Se)	7782-49-2	0.2 mg/m3	0.6 mg/m3	——	——
Selenium hexafluoride (as Se)	7783-79-1	0.05 ppm	0.15 ppm	——	——
Sesone (Crag herbicide)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sevin (Carbaryl)	63-25-2	5 mg/m3	10 mg/m3	——	——
Silane (see Silicon tetrahydride)	7803-62-5	5 ppm	10 ppm	——	——
Silica, amorphous, precipitated and gel	112926-00-8	6 mg/m3	12 mg/m3	——	——
Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica	61790-53-2	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Silica, crystalline cristobalite	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	14464-46-1	0.05 mg/m3	0.15 mg/m3	——	——
Silica, crystalline quartz	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	14808-60-7	0.1 mg/m3	0.3 mg/m3	——	——
Silica, crystalline tripoli (as quartz)	——	——	——	——	——
Respirable fraction	1317-95-9	0.1 mg/m3	0.3 mg/m3	——	——
Silica, crystalline tridymite	——	——	——	——	——
Respirable fraction Applies where the exposure limit in chapter 296-840 WAC is not in effect.	15468-32-3	0.05 mg/m3	0.15 mg/m3	——	——
Silica, fused	——	——	——	——	——
Respirable fraction	60676-86-0	0.1 mg/m3	0.3 mg/m3	——	——
Silicates (less than 1% crystalline silica)	——	——	——	——	——
Mica	——	——	——	——	——
Respirable fraction	12001-26-2	3 mg/m3	6 mg/m3	——	——
Soapstone	——	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Talc (containing asbestos) (as asbestos) (see WAC 296-62-07705 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Talc (containing no asbestos)	——	——	——	——	——
Respirable fraction	14807-96-6	2 mg/m3	4 mg/m3	——	——
Tremolite (asbestiform) (as asbestos) (see WAC 296-62-07705 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Silicon	7440-21-3	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Silicon carbide	409-21-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Silicon tetrahydride (Silane)	7803-62-5	5 ppm	10 ppm	——	——
Silver, metal dust and soluble compounds (as Ag)	7440-22-4	0.01 mg/m3	0.03 mg/m3	——	——
Soapstone	——	——	——	——	——
Total particulate	——	6 mg/m3	12 mg/m3	——	——
Respirable fraction	——	3 mg/m3	6 mg/m3	——	——
Sodium azide (as HN3 or NaN3)	26628-22-8	——	——	0.1 ppm	X
Sodium bisulfite	7631-90-5	5 mg/m3	10 mg/m3	——	——
Sodium-2, 4-dichloro- phenoxyethyl sulfate (Crag herbicide)	136-78-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sodium fluoroacetate	62-74-8	0.05 mg/m3	0.15 mg/m3	——	X
Sodium hydroxide	1310-73-2	——	——	2 mg/m3	——
Sodium metabisulfite	7681-57-4	5 mg/m3	10 mg/m3	——	——
Starch	9005-25-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Stibine	7803-52-3	0.1 ppm	0.3 ppm	——	——
Stoddard solvent	8052-41-3	100 ppm	150 ppm	——	——
Strychnine	57-24-9	0.15 mg/m3	0.45 mg/m3	——	——
Styrene (Phenylethylene, Vinyl benzene)	100-42-5	50 ppm	100 ppm	——	——
Subtilisins	9014-01-1	——	0.00006 mg/m3	——	——
			(60 min.)
Sucrose	57-50-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Sulfotep (TEDP)	3689-24-5	0.2 mg/m3	0.6 mg/m3	——	X
Sulfur dioxide	7446-09-5	2 ppm	5 ppm	——	——
Sulfur hexafluoride	2551-62-4	1,000 ppm	1,250 ppm	——	——
Sulfuric acid	7664-93-9	1 mg/m3	3 mg/m3	——	——
Sulfur monochloride	10025-67-9	——	——	1 ppm	——
Sulfur pentafluoride	5714-22-1	——	——	0.01 ppm	——
Sulfur tetrafluoride	7783-60-0	——	——	0.1 ppm	——
Sulfuryl fluoride	2699-79-8	5 ppm	10 ppm	——	——
Sulprofos	35400-43-2	1 mg/m3	3 mg/m3	——	——
Systox (Demeton)	8065-48-3	0.01 ppm	0.03 ppm	——	X
2, 4, 5-T (2, 4, 5- tri- chlorophenoxyacetic acid)	93-76-5	10 mg/m3	20 mg/m3	——	——
Talc (containing asbestos) (as asbestos) (see WAC 296-62-07705 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Talc (containing no asbestos)	——	——	——	——	——
Respirable fraction	14807-96-6	2 mg/m3	4 mg/m3	——	——
Tantalum	——	——	——	——	——
Metal and oxide dusts	7440-25-7	5 mg/m3	10 mg/m3	——	——
TDI (Toluene-2, 4-diisocyanate)	584-84-9	0.005 ppm	0.02 ppm	——	——
TEDP (Sulfotep)	3689-24-5	0.2 mg/m3	0.6 mg/m3	——	X
Tellurium and compounds (as Te)	13494-80-9	0.1 mg/m3	0.3 mg/m3	——	——
Tellurium hexafluoride (as Te)	7783-80-4	0.02 ppm	0.06 ppm	——	——
Temephos (Abate)	3383-96-8	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
TEPP	107-49-3	0.004 ppm	0.012 ppm	——	X
Terphenyls	26140-60-3	——	——	0.5 ppm	——
1, 1, 1, 2-Tetrachloro-2, 2-difluoroethane	76-11-0	500 ppm	625 ppm	——	——
1, 1, 2, 2-Tetrachloro-1, 2-difluoroethane	76-12-0	500 ppm	625 ppm	——	——
1, 1, 2, 2-Tetrachloroethane	79-34-5	1 ppm	3 ppm	——	X
Tetrachloroethylene (Perchloroethylene)	127-18-4	25 ppm	38 ppm	——	——
Tetrachloromethane (Carbon tetrachloride)	56-23-5	2 ppm	4 ppm	——	X
Tetrachloronaphthalene	1335-88-2	2 mg/m3	4 mg/m3	——	X
Tetraethyl lead (as Pb)	78-00-2	0.075 mg/m3	0.225 mg/m3	——	X
Tetrahydrofuran	109-99-9	200 ppm	250 ppm	——	——
Tetramethyl lead (as Pb)	75-74-1	0.075 mg/m3	0.225 mg/m3	——	X
Tetramethyl succinonitrile	3333-52-6	0.5 ppm	1.5 ppm	——	X
Tetranitromethane	509-14-8	1 ppm	3 ppm	——	——
Tetrasodium pyrophosphate	7722-88-5	5 mg/m3	10 mg/m3	——	——
Tetryl (2, 4, 6-trinitrophenyl- methylnitramine)	479-45-8	1.5 mg/m3	3 mg/m3	——	X
Thallium (soluble compounds) (as Tl)	7440-28-0	0.1 mg/m3	0.3 mg/m3	——	X
4, 4-Thiobis (6-tert-butyl-m-cresol)	96-69-5	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Thiodan (Endosulfan)	115-29-7	0.1 mg/m3	0.3 mg/m3	——	X
Thioglycolic acid	68-11-1	1 ppm	3 ppm	——-	X
Thionyl chloride	7719-09-7	——	——	1 ppm	——
Thiram (see WAC 296-62-07519)	137-26-8	5 mg/m3	10 mg/m3	——	——
Tin (as Sn)	——	——	——	——	——
Inorganic compounds	7440-31-5	2 mg/m3	4 mg/m3	——	——
Tin (as Sn)	——	——	——	——	——
Organic compounds	7440-31-5	0.1 mg/m3	0.3 mg/m3	——	X
Tin oxide (as Sn)	21651-19-4	2 mg/m3	4 mg/m3	——	——
Titanium dioxide	13463-67-7	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
TNT (2, 4, 6-Trinitrotoluene)	118-96-7	0.5 mg/m3	1.5 mg/m3	——	X
Toluene	108-88-3	100 ppm	150 ppm	——	——
Toluene-2, 4-diisocyanate (TDI)	584-84-9	0.005 ppm	0.02 ppm	——-	——
m-Toluidine	108-44-1	2 ppm	4 ppm	——	X
o-Toluidine	95-53-4	2 ppm	4 ppm	——	X
p-Toluidine	106-49-0	2.0 ppm	4 ppm	——	X
Toxaphene (Chlorinated camphene)	8001-35-2	0.5 mg/m3	1 mg/m3	——	X
Tremolite (asbestiform) (as asbestos) (see WAC 296-62-07705 and chapter 296-65 WAC)	——	0.1 f/cc	1.0 f/cc (30 minutes)	——	——
Tributyl phosphate	126-73-8	0.2 ppm	0.6 ppm	——	——
Trichloroacetic acid	76-03-9	1 ppm	3 ppm	——	——
1, 2, 4-Trichlorobenzene	120-82-1	——	——	5 ppm	——
1, 1, 1-Trichloroethane (Methyl chloroform)	71-55-6	350 ppm	450 ppm	——	——
1, 1, 2-Trichloroethane	79-00-5	10 ppm	20 ppm	——	——
Trichloroethylene	79-01-6	50 ppm	200 ppm	——	——
Trichlorofluoromethane (Fluorotrichloromethane)	75-69-4	——	——	1,000 ppm	——
Trichloromethane (Chloroform)	67-66-3	2 ppm	4 ppm	——	——
Trichloronaphthalene	1321-65-9	5 mg/m3	10 mg/m3	——	X
1, 2, 3-Trichloropropane	96-18-4	10 ppm	20 ppm	——	X
1, 1, 2-Trichloro-1, 2, 2-trifluoroethane	76-13-1	1,000 ppm	1,250 ppm	——	——
Tricyclohexyltin hydroxide (Cyhexatin)	13121-70-5	5 mg/m3	10 mg/m3	——	——
Triethylamine	121-44-8	10 ppm	15 ppm	——	——
Trifluorobromomethane	75-63-8	1,000 ppm	1,250 ppm	——	——
Trimellitic anhydride	552-30-7	0.005 ppm	0.015 ppm	——	——
Trimethylamine	75-50-3	10 ppm	15 ppm	——	——
Trimethyl benzene	25551-13-7	25 ppm	38 ppm	——	——
Trimethyl phosphite	121-45-9	2 ppm	4 ppm	——	——
2, 4, 6-Trinitrophenol (Picric acid)	88-89-1	0.1 mg/m3	0.3 mg/m3	——	X
2, 4, 6-Trinitrophenyl- methylnitramine (Tetryl)	479-45-8	1.5 mg/m3	3 mg/m3	——-	X
2, 4, 6-Trinitrotoluene (TNT)	118-96-7	0.5 mg/m3	1.5 mg/m3	——	X
Triorthocresyl phosphate	78-30-8	0.1 mg/m3	0.3 mg/m3	——	X
Triphenyl amine	603-34-9	5 mg/m3	10 mg/m3	——	——
Triphenyl phosphate	115-86-6	3 mg/m3	6 mg/m3	——	——
Tungsten (as W)	7440-33-7	——	——	——	——
Soluble compounds	——	1 mg/m3	3 mg/m3	——	——
Insoluble compounds	——	5 mg/m3	10 mg/m3	——	——
Turpentine	8006-64-2	100 ppm	150 ppm	——	——
Uranium (as U)	7440-61-1	——	——	——	——
Soluble compounds	——	0.05 mg/m3	0.15 mg/m3	——	——
Insoluble compounds	——	0.2 mg/m3	0.6 mg/m3	——	——
n-Valeraldehyde	110-62-3	50 ppm	75 ppm	——	——
Vanadium (as V2O5)	——	——	——	——	——
Respirable fraction	1314-62-1	0.05 mg/m3	0.15 mg/m3	——	——
Vegetable oil mist	——	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Vinyl acetate	108-05-1	10 ppm	20 ppm	——	——
Vinyl benzene (Styrene)	100-42-5	50 ppm	100 ppm	——	——
Vinyl bromide	593-60-2	5 ppm	10 ppm	——	——
Vinyl chloride (Chloroethylene) (see WAC 296-62-07329)	75-01-4	1 ppm	5 ppm	——	——
Vinyl cyanide (Acrylonitrile) (see WAC 296-62-07336)	107-13-1	2 ppm	10 ppm	——	——
Vinyl cyclohexene dioxide	106-87-6	10 ppm	20 ppm	——	X
Vinyl toluene	25013-15-4	50 ppm	75 ppm	——	——
Vinylidene chloride (1, 1-Dichloroethylene)	75-35-4	1 ppm	3 ppm	——	——
VM & P Naphtha	8032-32-4	300 ppm	400 ppm	——	——
Warfarin	81-81-2	0.1 mg/m3	0.3 mg/m3	——	——
Welding fumes (total particulate)	——	5 mg/m3	10 mg/m3	——	——
Wood dust	——	——	——	——	——
Nonallergenic; (All woods except allergenics)	——	5 mg/m3	10 mg/m3	——	——
Allergenics (e.g. cedar, mahogany and teak)	——	2.5 mg/m3	5 mg/m3	——	——
Xylenes (ortho, meta, and para isomers) (Dimethylbenzene)	1330-20-7	100 ppm	150 ppm	——	——
m-Xylene alpha, alpha-diamine	1477-55-0	——	——	0.1 mg/m3	X
Xylidine (Dimethylaminobenzene)	1300-73-8	2 ppm	4 ppm	——	X
Yttrium	7440-65-5	1 mg/m3	3 mg/m3	——	——
Zinc chloride fume	7646-85-7	1 mg/m3	2 mg/m3	——	——
Zinc chromate (as Cr) (see WAC 296-62-08003)	Varies with compound	0.005 mg/m3	——	0.1 mg/m3	——
Zinc oxide	1314-13-2	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m	——	——
Zinc oxide fume	1314-13-2	5 mg/g3	10 mg/m3	——	——
Zinc stearate	557-05-1	——	——	——	——
Total particulate	——	10 mg/m3	20 mg/m3	——	——
Respirable fraction	——	5 mg/m3	10 mg/m3	——	——
Zirconium compounds (as Zr)	7440-67-2	5 mg/m3	10 mg/m3	——	——