WSR 08-12-109




[ Filed June 4, 2008, 11:00 a.m. , effective July 5, 2008 ]

     Effective Date of Rule: Thirty-one days after filing.

     Purpose: The sections below describe the information utilized by the department of labor and industries (L&I) to determine the necessity for a rule.

     A. Legal Requirements: The Washington state constitution mandates that "[t]he legislature shall pass laws for the protection of persons working in mines, factories, and other employments dangerous to life or deleterious to health."1 In enacting chapter 49.17 RCW, Washington Industrial Safety and Health Act (WISHA), the Washington legislature found "that personal injuries and illnesses arising out of conditions of employment impose a substantial burden upon employers and employees in terms of lost production, wage loss, medical expenses, and payment of benefits under the Industrial Insurance Act. Therefore, in the public interest for welfare of the people of the state of Washington and in order to assure, insofar as may be reasonably possible, safe and healthful working conditions for every man and woman working in the state of Washington, the legislature... in keeping with the mandates of Article II, section 35 of the state constitution, declares its purpose by the provisions of this chapter to create, maintain, continue, and enhance the industrial safety and health program of the state..."2

     WISHA mandates that the director of L&I shall "[p]rovide for the promulgation of health and safety standards and the control of conditions in all work places concerning... harmful physical agents which shall set a standard which most adequately assures, to the extent feasible, on the basis of the best available evidence, that no employee will suffer material impairment of health or functional capacity."3

     In Rios v. Department of Labor and Industries, the Washington supreme court concluded that L&I must consider rule making for recognized work place hazards.4

     B. Evaluation of Current Rules: On July 18, 2005, a farm worker collapsed while cutting weeds with a machete in hop fields near Yakima. He died, and the coroner ruled that the cause of death was heat stroke. L&I investigated the death and later cited and fined the company for an inadequate safety program, not providing drinking water, and lack of training for workers. The safety program should have included a plan to prevent heat stress by providing rest breaks, shade, worker hydration and administrative controls such as a work-rest regimen.

     The citation was issued December 23, 2005, and the subsequent appeal was affirmed with a negotiated penalty of $3,000. L&I did not seek criminal sanctions since the violations cited were not considered willful (a prerequisite for a referral to a county prosecuting attorney).

     Immediately following this workplace death, L&I heard from farm worker advocates that they were very concerned about this fatality and that they wanted an emergency rule issued similar to California's emergency heat-stress rule. L&I responded by issuing a hazard alert to the agriculture industry, and then proceeded with a study5 to determine what was needed to protect workers for the 2006 summer season.

     L&I reviewed the workers' compensation injury and illness claims from 1995 through 2005 and found that one other person had died from heat stress in Washington (a lawn-service employee working in the Yakima area). The study also found approximately four hundred fifty workers' compensation claims for heat-related illness during the same time period. These fatalities may have been prevented with rules that are more protective of workers.

     Based on this information, L&I evaluated its existing rules to determine if they adequately addressed heat-related illness. These rules are available in Appendix 1: Pertinent rules for heat-related illness. After this evaluation, L&I believed that these fatalities and illnesses may have been prevented by adopting a consolidated set of rules specifically addressing heat-related illness issues.

     C. Petition for Rule Making: On January 27, 2007, the department received the following petition - "Petition for Rule Making: Permanent Rules Protecting Outdoor Employees From Heat Illness."

     The petitioner, Erasto Garcia, and his attorneys, Candelaria Murillo and Daniel G. Ford of Columbia Legal Services, petitioned the department to adopt permanent rules protecting outdoor workers from heat illness.

     They argued permanent rules on heat illness are necessitated by: "(i) The severity of the health effects associated with occupational heat illness, including three documented heat-related illness deaths in Washington state in the last three summer seasons; (ii) the threat of exposure inherent in working outdoors during the hotter months in Washington; and (iii) the significant risk of heat illness among farm workers and other outdoor workers."6 As set forth more fully below, an estimated six million workers in [the] United States are exposed to occupational heat stress.

     In addition, the petitioner argued that heat illness prevention is feasible, has been determined to be effective in reducing outdoor workers' exposure to heat illness, and has been mandated in California. The petitioner further argued WISHA requires L&I to adopt feasible and necessary rules to protect the health and lives of Washington workers.

     The petitioner provided a suggested draft rule for L&I's consideration. L&I responded by clarifying that a CR-101 (preproposal statement of inquiry) had been filed communicating L&I's intention to initiate a permanent rule making.

     D. Health Effects Associated with Heat-Related Illness: Heat-related illness is a hazard recognized by the Occupational Safety and Health Administration (OSHA), National Institute for Occupational Safety and Health (NIOSH), Center for Disease Control (CDC), as well as industry associations and employee representatives. The numbers of employees potentially exposed to heat-related illness hazards include many industries and regional areas of the state. L&I also considered the severity of the hazard. Heat-related illness can cause serious injuries including death. The extract below explains the health effects of heat-related illness: Minor heat illnesses include heat cramps and heat exhaustion. Major heat injuries include EHI, exertional rhabdomyolysis, and heat stroke. The diagnostic categories of heat exhaustion, EHI, and heat stroke have overlapping features and should be thought of as different regions on a continuum rather than discrete disorders, each with its own distinct pathogenesis.

     Figure 4-1 depicts the spectrum of heat casualties in terms of severity and categories of physiological dysfunction (hyperthermia, dehydration, nephropathy, cell lysis, encephalopathy). Whatever category is diagnosed, all are related to elevation of body core temperature and the metabolic and circulatory processes (including change in fluid and electrolyte balance) that are brought about by heat strain from exercise, environment and the body's thermoregulatory response.

Figure 4-1. Spectrum of heat casualties, encompassing the continuum of mild (heat exhaustion) to sever (heat stroke) with association categories of physiologic dysfunction.7

     E. Fatality Summaries:
During the review of occupational heat-related illness claims in Washington state, L&I discovered four fatalities that occurred as a result of heat-related illness. A summary of these fatalities is presented below.

     Yakima, Washington - May 1997: A thirty-five year old male, previously employed indoors, died of heat stroke during his first day of employment outdoors mowing lawns on May 12, 1997. The patient's internal temperature was 111°F. The high temperature for that day was 88°F. The employee had been mowing lawns and in the afternoon he was feeling tired and he was told to go to the company truck to rest. When another employee checked on him, he was talking to himself and would not respond to his coworker. His brother was called over and he could not get a response so 911 was called. He died shortly after arriving at the hospital after going into full cardiopulmonary arrest. The official cause of death was listed as hyperthermia. His brother stated that the employee did not drink fluids readily since the water that he had brought had become hot.

     Vancouver, Washington - July 2004: A thirty-nine year old male roofer was working on a roof in the sun doing tar work when he collapsed on July 12, 2004. The day's temperature was about 90°[F] at the time of the incident. The employee was minimally responsive when medics arrived and had a rectal temperature of 108°[F] when measured at the hospital. The employee had an underlying alcoholism problem and went through alcohol withdrawal while in the hospital. The diagnoses were heat stroke with dehydration, shock liver, and alcoholism. He was released from the hospital on July 16, 2004, but had ongoing problems with feeling weak and bloated, dizziness, short-term memory lapses and multiple medical problems related to his liver disease and associated problems. He entered an alcohol treatment program and was diagnosed with severe preexisting liver disease that was exacerbated by the industrial injury. The employee was placed on a liver transplant list. On May 18, 2006, the employee passed away from liver disease complications.

     Moxee, Washington - July 2005: A sixty-four year old male, cutting in a hop field where he had reportedly worked for forty years, was found unconscious. It is unknown how long he was down before he was discovered. Approximately eight to ten minutes later the EMTs arrived and found no vital signs. The EMTs revived a heart rhythm while he was being transported to the hospital where he died several hours later. The death was recorded as heat stroke. The high temperature that day was 99°F. He arrived five - ten minutes late for work that day, uncharacteristic for him, due to not feeling well. He had brought two gallons of water with him that day but had drank all of it by lunchtime. The workers normally brought their own water to work. The foreman had not brought water for the employees that morning. The employees would work down rows individually and would check in with each other at the end of a row. The employees were allowed to take breaks whenever they needed one. The employees were paid by how many rows they completed versus being paid by time. Each row was approximately three hundred fifty feet long (a little longer than a football field). The decedent had completed one row already that day. He was found approximately 1/3 down a row between 11:15 and 11:30 a.m. The employees had taken a break right before he was found. The employer did not provide heat stress training. The employer did place a reminder sticker to increase fluid intake in hot weather on the paychecks.

     Carson, Washington - June 2006: A twenty-seven year old male was working with a utility contractor laying an underground water line along a public road on June 26, 2006. The employee was working in the trench with the pipe placement plus jumping out to retrieve tools and materials. Between 2:30 and 3:00, the individual became disoriented and was told to rest in the shade. Soon after, he lost consciousness. He never regained consciousness and died on July 1, 2006. His date of hire was June 16, 2006. The temperature ranged from 82°F to 105°F that day and the employee's temperature was 107°[F] when taken by EMS upon arrival.

     F. Hospitalization Summaries: During L&I's review of heat-related illness claims in Washington state, many cases of hospitalization were discovered. The summaries below provide an overview of two cases that were brought to L&I's attention during the rule-making process.

     Seattle, Washington - June 2000: A forty-seven year old male firefighter suffered heat-related illness and lost consciousness on a ladder while conducting a training exercise. The patient was holding a weighted dummy. A fellow firefighter tried to hold him up on the ladder but was unsuccessful. The patient fell approximately thirty-five feet to the ground below. Although the patient did not pass away from his injuries, he was determined to have a permanent partial disability as a result of the incident and was unable to return to work in his current position.

     Southwestern Washington - August 1999: A twenty-three year old male suffered heat stroke during his first day of employment as a choker setter for a logging operation on August 23, 1999. His body temperature at the time he was admitted to the hospital was 106.7°F. Reports suggested that he had been prevented by his supervisor from drinking water. Severe dehydration, reduced ability of the body to cool itself due to heavy protective clothing, and a high metabolic (work) heat load combined to overwhelm this individual's thermoregulatory responses. Although the patient survived, he continued to suffer from liver dysfunction and other chronic health issues resulting from the incident. The high temperature on the date/place of occurrence could not be determined.

     G. Injury and Illness Claim Review: L&I reviewed accepted claims resulting from heat-related illness. Although L&I believes heat-related illness claims are underreported due to the symptoms, the frequency of claims is just one of several factors L&I considered when evaluating the need to initiate rule making to address this hazard. Claims data also shows that heat-related illness has directly contributed to other serious injuries (such as falls from ladders).

     The safety and health assessment and research project (SHARP) conducted a study on heat-related illness claims in Washington state. Information on the report is available online at The full report (publication number 59-1-2006) is available at no cost by contacting SHARP at 1-800-66-SHARP or by e-mail at

     This report has been published as follows: Bonauto D, Anderson R, Rauser E, Burke B. (2007). "Occupational Heat Illness in Washington State, 1995-2005," American Journal of Industrial Medicine. A summary of the article is provided below.

     An analysis of HRI cases utilizing workers' compensation data has not been previously reported. Authors used both ICD-9 and ANSI-Z16.2 codes with subsequent medical record review to identify accepted Washington State Fund workers' compensation HRI during the eleven-year study period. NAICS industries with the highest workers' compensation HRI average annual claims incidence rate were Fire Protection 80.8/100,000 FTE, Roofing Construction 59.0/100,000 FTE, and Highway Bridge and Street Construction 44.8/100,000 FTE. HRI claims were associated with high outdoor ambient temperatures.

     Exertional heat stroke occurs sporadically in individuals with high metabolic output rates and is most prevalent during hot and humid weather. Exertional HRI results from high metabolic demands often in combination with hot environmental conditions.

     HRI claims were identified by a two-step process. First, workers' compensation claims were identified using data systems definitions (selected ICD-9 codes and ANSI-Z16.2 codes). Identified claims underwent physician review to determine if the claim was filed for a [an] HRI. This study was restricted to state fund claims because ICD-9 codes are not available for self-insured claims.

     Of the nine hundred forty-six claims identified using the HRI ICD-9 codes or ANSI-Z16.2 type code 151, four hundred ninety-two were HRI claims after medical review of the electronic claim text fields and medical records. Subtracting out employers with a physical location outside of Washington, identified four hundred eighty HRI claims occurred during the study period.

     Of the four hundred eighty HRI claims, four hundred forty-two (92.1%) were classified as "noncompensable" (medical only) and thirty-eight (7.9%) were considered "compensable" (greater than three lost work days).

     The average age of an HRI claimant was thirty-five years old and the median age was thirty-four years. The proportion of HRI claimant under twenty-five years old was significantly more than the proportion of all state fund claimants under twenty-five years old. The average age of the worker with an HRI compensation claim was forty-one years which is comparable to the average age for all state fund compensable claimants at thirty-nine years old.

     The cumulative cost for the eleven-year period for all HRI claims was $895,196 and ranged from $0 to $216,449. Thirty-four claims received time-loss compensation ranging from one to six hundred fifty-nine days.

     HRI claim incidence rates by industry sector were highest in construction at 12.1 per 100,000 FTE, Public Administration at 12.0 per 100,000 FTE, Forestry, Fishing, and Hunting at 5.2 per 100,000 FTE. The distribution of HRI claims differs from that of all state fund accepted claims with an excess proportion of claims occurring mostly in construction and public administration.

     Of the four hundred eighty claims, three hundred seventy-seven (78.5%) occurred as a result of outdoor work. In construction, 16/159 (10.1%) claims were compensable (lost work days greater than three days), while in Agriculture, Forestry and Fishing, 7/33 (21.2%) claims were compensable. None of the eighty-five claims in the public administration sector were compensable.

     NAICS Industries with the highest annual claim incidence rates include Fire Protection at 80.8 per 100,000 FTE, Roofing Construction 59.0 per 100,000 FTE and Highway, Street and Bridge Construction at 44.8 per 100,000 FTE. In Roofing Construction, 18.5% (5/27) of the claims were compensable.

     HRI claim rates for the third quarter, the reporting period matching the greatest level of exposure to elevated environmental temperatures, far exceed the annual HRI claim incidence rate. The highest third quarter rates by NAICS industry were for Roofing Construction at 161.2 per 100,000 FTE and for Fire Protection at 158.8 per 100,000 FTE.

     Compensable claims were most common in roofers and miscellaneous agricultural workers were five of twenty-three (21.7%) and four of twenty (20%) were compensable, respectively.

     The average number of HRI claims per year was forty-four and the annual number of claims ranged from twenty-eight to seventy-three. From May through September, four hundred fifty-six (95.0%) HRI claims occurred. However, 82.7% of the HRI claims occurred during the three months of June, July, and August.

     Eighty-eight days during the study period had multiple HRI claims, a cluster, and represent two hundred sixty claims or 54.2% of all claims. Eighty-three of the eighty-eight days with a cluster of HRI claims were in June through August. The number of HRI claims in a cluster ranged from two to fifteen claims. Fifty-five of the one hundred three (53.4%) indoor claims and two hundred five of the three hundred seventy-seven (54.4%) outdoor claims were part of a cluster.

     There were four hundred fifteen individual employer accounts with an accepted HRI claim during the study period. The number of claims per employer ranged from one to eight. Forty employer accounts had more than one HRI claim during the study period. Only two employer accounts had multiple HRI claims in a single day.

     Hour of injury was determined for three hundred ninety-nine of the four hundred eighty claims. Of the three hundred ninety-nine claims, three hundred fifty-eight (89.7%) occurred between 10 a.m. and 6 p.m. and 80.4% were from heat exposure outdoors. Approximately 24% of all state fund workers' compensation claims occur in eastern Washington but the area accounted for two hundred twenty (45.6%) of the HRI claims.

     The daily max temperature interquartile range for all HRI claims was 77°F - 94°F (i.e. 25% of the HRI claims occurred below 77°F, 25% occurred with temperatures above 94°F and the remaining 50%, the interquartile range, were between those two temperatures). The average maximum temperature for the three hundred eight days in which an HRI claim occurred was 80.8°F.

     The geographic distribution of claims, eastern Washington compared to western Washington, on days with multiple HRI claims compared to days with a single HRI claim did not significantly differ. However, there was a statistically significant difference between the average max temperature for days in which a single claim occurred (Tmax average 80.4°F) and the average Tmax for days with multiple HRI claims (Tmax avg. 88.5°F). When reviewing the daily Tmax for the three days preceding the HRI claim, two hundred of the four hundred eighty HRI claims (41.7%) were noted to have a 10° increase in the Tmax.

     There were one hundred six (22.1%) HRI claims here medication use or a medical condition may have played a contributing role to the development of the HRI. Twenty workers reported a history of a previous HRI or treated dehydration but no HRI claimant had filed multiple HRI claims during the study period.

     Of the four hundred eighty HRI claims, three hundred eight had information on the duration of employment. Of the three hundred eight, forty-three (14%) claimants reported employment of one week or less. For all state fund claims, the proportion of claimants reporting employment of one week or less before their day of injury was 3.3%.

     Industries with the highest claim rates reflect those with increased outdoor work exposure. Claims occurring in an indoor environment also were common during the summer months, suggesting a relationship with outside temperatures.

     The most apparent risk factor for increased Washington incidence of HRI is higher outdoor temperatures experienced from May through September. It was found that 95% of total HRI claims occurred during these months. Similar results are apparent for other occupational and military studies. July is the month associated with the highest incidence rates for all three studies.

     Data suggests a dose-response effect of environmental ambient temperature on HRI claims incidence. The hottest parts of the day, 10 a.m. to 6 p.m., coincided with the greatest number of HRI claims. Other data suggest that high exertion levels, alone or in conjunction with high ambient temperatures, increase the risk for HRI. Lack of acclimatization is a well known risk factor for HRI. This data indicates HRI claims occurring within one week of employment occurred more than four times as frequently as workers suffering injuries from all causes within that time period.

     Cases associated with a cluster of claims were more likely associated with variation in temperature during the days preceding the injury. Thus poor acclimatization may play a larger role in occupational HRI cases than can be measured using the data available.

     Awareness of the medical conditions, medications or personal risk factors that place an individual at risk for HRI should be a required component of a training program.

     The limitations to this descriptive study include the likely underreporting of HRI to the workers' compensation system and the under-recognition of HRI by workers, employers and the medical community. There is a possibility of misclassification of HRI workers' compensation claims to other diagnosis if the injury was poorly described on the workers' compensation claim form.

     The current study and work of others indicate that increased summertime outdoor temperatures are associated with higher exertional HRI incidence rates. Consequently, education, planning, and resources aimed at prevention should be in place prior to significant seasonal exposure.

     Intervention studies suggest the value of anticipating high temperatures, assessing environmental conditions, and implementing preventative changes that reduce metabolic heat loading when necessary. Current military HRI prevention practices include considerations such as heat illness recognition and prevention training; WGBT-based environmental assessment, guidelines for work/rest cycles, and guidelines for water intake.

     Optimally, employers should have a comprehensive heat stress prevention program that identifies heat stress hazards, assess the hazards in terms of severity and probability, implements the appropriate controls, and continuously evaluates the effectiveness of these controls. Thus, components of an employers' written comprehensive heat illness prevention program will include engineering controls, appropriate work practices for environmental conditions, employee training, personal protective equipment, and preventive medical practices.

     The most apparent association for exertional HRI is exposure to increased ambient temperatures during summer months. Personal risk factors including co-morbid medical conditions, medications, illicit drug and alcohol use and limited acclimatization were present in some cases. Incorporation of prevention programs into the workplace may increase recognition and promote the prevention of HRI.

     H. Chronological Summary of Outdoor Heat Exposure Rule-making Project:

July 2005 Sixty-five year old male dies cutting weeds in a hop field near Yakima on July 18, 2005. Temperature was in the 90s.
Representative Phyllis Kenney and Mexican Consulate work with L&I Director Gary Weeks on responsive action to death.
December 2005 Department distributes first draft HRI rule for stakeholder comment.
January 2006 Department meets with stakeholders to discuss draft rule language.
February 2006 Department discusses the HRI draft with the WISHA advisory committee.
March 2006 Department distributes an updated HRI draft and works with stakeholders on language.
June 2006 Department adopts an emergency rule on June 1, 2006. The emergency rule changes language in an existing rule in WAC 296-62-09013 to apply the requirement to the outdoor environment. The rule is in effect for one hundred twenty days.
May 2006 Forty-one year old male dies after experiencing heat stroke in July 2004. His death was determined to be a result of the heat stroke event.
July 2006 Twenty-seven year old male dies after experiencing HRI on June 26, 2006, laying pipe in/near Vancouver, Washington. Temperature was approximately 100ºF.
September 2006 The 2006 emergency rule expires on September 28, 2006.
November 2006 Department meets with stakeholders to discuss 2006 emergency rule.
December 2006 The department files a CR-101 (preproposal) on December 19, 2006.
January 2007 Department receives a petition for rule making from Columbia Legal Services.
February 2007 Department meets with stakeholders to discuss draft HRI rule.
April 2007 Department distributes draft emergency rule to stakeholders on April 16, 2007. Training materials and the training course schedule was also distributed.
June 2007 Emergency rule is adopted on June 5, 2007, with enforcement delayed until June 18, 2007, and July 1, 2007. The rule is in effect for one hundred twenty days.
August 2007 Department begins to solicit comments of the emergency rule language.
September 2007 Department holds stakeholder meetings on the draft language around the state.
October 2007 The 2007 emergency rule expires on October 3, 2007.
November 2007 Department meets with a business-labor committee to discuss draft rule language.
March 2008 Department files a proposed HRI rule on March 19, 2008, and begins accepted written comment on the proposed language.
April 2008 Department holds a public hearing in Tumwater, Washington on April 28.
Department holds a public hearing in Bellingham, Washington on April 29.
Department holds a public hearing in Yakima, Washington on April 30.
Department holds a public hearing in Richland, Washington on April 30.
May 2008 Department holds a public hearing in Spokane, Washington on May 1.
Department holds a public hearing in Seattle, Washington on May 2.
Department extends comment period from May 2, 2008, to May 9, 2008.
June 2008 Department adopts a permanent outdoor heat exposure rule.

1 Wash. Const. Art. 2 § 35.

2 RCW 49.17.010.

3 RCW 49.17.050(4).

4 Rios v. Department of Labor & Industries, 145 Wn.2d 483, 500, 39 P.3d 961 (2002).

5 Bonauto D, Anderson R, Rauser E, Burke B. (2007). "Occupational Heat Illness in Washington State, 1995-2005," American Journal of Industrial Medicine. A summary of the article is provided below.

6 Petition for Rule Making: Permanent Rules Protecting Outdoor Employees from Heat Illness, p. 1, ¶ 1.2.

7 Department of the Army and Air Force (2003). "Technical Bulletin: Heat Stress Control and

Heat Casualty Management." Washington, DC: Headquarters, Department of the Army and Air Force.

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

      Adopted under notice filed as WSR 08-07-098 on March 19, 2008.

     Changes Other than Editing from Proposed to Adopted Version: Rule Requirement of the Proposed Rule Compared to the Adopted Rule: The table below provides a summary of the changes made from the proposed version of the rule to the adopted version.

Proposed Rule Recommendations for Adoption
Scope •     Applied to employers with outdoor employees and exempts employees working outdoors for fifteen minutes or less in an hour over the entire workshift (incidental exposure).

•     Provided temperature triggers for when the requirements for drinking water and responding to signs and symptoms apply.

•     Updates the language to limit application of all of the rule requirements when the temperature action levels are met or exceeded.

•     Adds language limiting the application of the rule from May 1 through September 30 annually.

•     Removes half of the temperature action levels to streamline application.

•     Adds language to clearly exempt employees with incidental exposure from the rule requirements.

•     Clarifies language as a result of comments received.

Definitions •     Provided definitions of "environmental risk factors," "heat-related illness," "heat-related illness hazard," "incidental exposure," "outdoor environment," and "personal factors..." •     Removes definitions of "heat-related illness hazard," "incidental exposure," and "personal risk factors..."

•     Adds definitions of "double-layer woven clothing," and "vapor barrier clothing."

•     Updates the definition of "drinking water" to clearly allow the use of electrolyte beverages.

•     Clarifies language as a result of comments received.

Employer and employee responsibility •     Required a specific written program to address HRI if employees work outdoors.

•     Provided specific elements that the program must address.

•     Changes language to allow employers to address HRI in their accident prevention program (currently required).

•     Removes requirements for specific elements of the written program.

•     Clarifies language as a result of comments received.

Drinking water Required employers to provide one quart of water per hour per employee when the temperature triggers are met or exceeded. Clarifies language as a result of comments received.
Responding to signs and symptoms... •     Applied to employers with employees working in the outdoor environment for more than fifteen minutes in an hour.

•     Required employees showing signs or demonstrating symptoms of HRI to be relieved from duty when temperature triggers are met or exceeded.

•     Applies to employers with employees working in the outdoor environment for more than fifteen minutes in an hour and temperatures meet or exceed the temperature action levels in Table 1.

•     Removes language providing examples which caused confusion.

Information and training •     Applied to employers with employees working in the outdoor environment for more than fifteen minutes in an hour.

•     Required annual training on HRI if employees work outdoors.

•     Provided training topics for employees and supervisors.

•     Applies to employers with employees working in the outdoor environment for more than fifteen minutes in an hour and temperatures meet or exceed the temperature action levels in Table 1.

•     Streamlines the training topics by removing topics that are covered by other rules or will have less impact on HRI prevention.

•     Clarifies rule language as a result of comments received.

     A final cost-benefit analysis is available by contacting Jamie Scibelli, P.O. Box 44620, Olympia, WA 98504-4620, phone (360) 902-4568, fax (360) 902-5619, e-mail

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

     Number of Sections Adopted at Request of a Nongovernmental Entity: New 7, Amended 0, Repealed 0.

     Number of Sections Adopted on the Agency's Own Initiative: New 7, Amended 0, Repealed 0.

     Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 7, Amended 0, 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 7, Amended 0, Repealed 0.

     Date Adopted: June 4, 2008.

Judy Schurke



WAC 296-62-095   Outdoor heat exposure.  


WAC 296-62-09510   Scope and purpose.   (1) WAC 296-62-095 through 296-62-09560 applies to all employers with employees performing work in an outdoor environment.

     (2) The requirements of WAC 296-62-095 through 296-62-09560 apply to outdoor work environments from May 1 through September 30, annually, only when employees are exposed to outdoor heat at or above an applicable temperature listed in Table 1.

     Table 1

     To determine which temperature applies to each worksite, select the temperature associated with the general type of clothing or personal protective equipment (PPE) each employee is required to wear.

Outdoor Temperature Action Levels

All other clothing 89°
Double-layer woven clothes including coveralls, jackets and sweatshirts 77°
Nonbreathing clothes including vapor barrier clothing or PPE such as chemical resistant suits 52°

Note: There is no requirement to maintain temperature records. The temperatures in Table 1 were developed based on Washington state data and are not applicable to other states.

     (3) WAC 296-62-095 through 296-62-09560 does not apply to incidental exposure which exists when an employee is not required to perform a work activity outdoors for more than fifteen minutes in any sixty-minute period. This exception may be applied every hour during the work shift.

     (4) WAC 296-62-095 through 296-62-09560 supplement all industry-specific standards with related requirements. Where the requirements under these sections provide more specific or greater protection than the industry-specific standards, the employer shall comply with the requirements under these sections. Additional related requirements are found in chapter 296-305 WAC, Safety standards for fire fighters and chapter 296-307 WAC, Safety standards for agriculture.


WAC 296-62-09520   Definitions.   (1) Acclimatization means the body's temporary adaptation to work in heat that occurs as a person is exposed to it over time.

     (2) Double-layer woven clothing means clothing worn in two layers allowing air to reach the skin. For example, coveralls worn on top of regular work clothes.

     (3) Drinking water means potable water that is suitable to drink. Drinking water packaged as a consumer product and electrolyte-replenishing beverages (i.e., sports drinks) that do not contain caffeine are acceptable.

     (4) Engineering controls means the use of devices to reduce exposure and aid cooling (i.e., air conditioning).

     (5) Environmental factors for heat-related illness means working conditions that increase susceptibility for heat-related illness such as air temperature, relative humidity, radiant heat from the sun and other sources, conductive heat sources such as the ground, air movement, workload (i.e., heavy, medium, or low) and duration, and personal protective equipment worn by employees. Measurement of environmental factors is not required by WAC 296-62-095.

     (6) Heat-related illness means a medical condition resulting from the body's inability to cope with a particular heat load, and includes, but is not limited to, heat cramps, heat rash, heat exhaustion, fainting, and heat stroke.

     (7) Outdoor environment means an environment where work activities are conducted outside. Work environments such as inside vehicle cabs, sheds, and tents or other structures may be considered an outdoor environment if the environmental factors affecting temperature are not managed by engineering controls. Construction activity is considered to be work in an indoor environment when performed inside a structure after the outside walls and roof are erected.

     (8) Vapor barrier clothing means clothing that significantly inhibits or completely prevents sweat produced by the body from evaporating into the outside air. Such clothing includes encapsulating suits, various forms of chemical resistant suits used for PPE, and other forms of nonbreathing clothing.


WAC 296-62-09530   Employer and employee responsibility.   (1) Employers of employees exposed at or above temperatures listed in WAC 296-62-09510(2) Table 1 must:

     (a) Address their outdoor heat exposure safety program in their written accident prevention program (APP); and

     (b) Encourage employees to frequently consume water or other acceptable beverages to ensure hydration.

     (2) Employees are responsible for monitoring their own personal factors for heat-related illness including consumption of water or other acceptable beverages to ensure hydration.


WAC 296-62-09540   Drinking water.   (1) Keeping workers hydrated in a hot outdoor environment requires that more water be provided than at other times of the year. Federal OSHA and research indicate that employers should be prepared to supply at least one quart of drinking water per employee per hour. When employee exposure is at or above an applicable temperature listed in WAC 296-62-09510(2) Table 1:

     (a) Employers must ensure that a sufficient quantity of drinking water is readily accessible to employees at all times; and

     (b) Employers must ensure that all employees have the opportunity to drink at least one quart of drinking water per hour.

     (2) Employers are not required to supply the entire quantity of drinking water needed to be supplied for all employees on a full shift at the beginning of the shift. Employers may begin the shift with smaller quantities of drinking water if effective procedures are established for replenishment during the shift.


WAC 296-62-09550   Responding to signs and symptoms of heat-related illness.   (1) Employees showing signs or demonstrating symptoms of heat-related illness must be relieved from duty and provided with a sufficient means to reduce body temperature.

     (2) Employees showing signs or demonstrating symptoms of heat-related illness must be monitored to determine whether medical attention is necessary.


WAC 296-62-09560   Information and training.   All training must be provided to employees and supervisors, in a language the employee or supervisor understands, prior to outdoor work which exceeds a temperature listed in WAC 296-62-09510(2) Table 1, and at least annually thereafter.

     (1) Employee training. Training on the following topics must be provided to all employees who may be exposed to outdoor heat at or above the temperatures listed in WAC 296-62-09510(2) Table 1:

     (a) The environmental factors that contribute to the risk of heat-related illness;

     (b) General awareness of personal factors that may increase susceptibility to heat-related illness including, but not limited to, an individual's age, degree of acclimatization, medical conditions, drinking water consumption, alcohol use, caffeine use, nicotine use, and use of medications that affect the body's responses to heat. This information is for the employee's personal use;

     (c) The importance of removing heat-retaining personal protective equipment such as nonbreathable chemical resistant clothing during all breaks;

     (d) The importance of frequent consumption of small quantities of drinking water or other acceptable beverages;

     (e) The importance of acclimatization;

     (f) The different types of heat-related illness, the common signs and symptoms of heat-related illness; and

     (g) The importance of immediately reporting signs or symptoms of heat-related illness in either themselves or in co-workers to the person in charge and the procedures the employee must follow including appropriate emergency response procedures.

     (2) Supervisor training. Prior to supervising employees working in outdoor environments with heat exposure at or above the temperature levels listed in WAC 296-62-09510(2) Table 1, supervisors must have training on the following topics:

     (a) The information required to be provided to employees listed in subsection (1) of this section;

     (b) The procedures the supervisor must follow to implement the applicable provisions of WAC 296-62-095 through 296-62-09560;

     (c) The procedures the supervisor must follow if an employee exhibits signs or symptoms consistent with possible heat-related illness, including appropriate emergency response procedures; and

     (d) Procedures for moving or transporting an employee(s) to a place where the employee(s) can be reached by an emergency medical service provider, if necessary.


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