PDFWAC 246-366-110

Sound control.

(1) In new construction, plans submitted under WAC 246-366-040 shall specify ventilation equipment and other mechanical noise sources in classrooms are designed to provide background sound which conforms to a noise criterion curve or equivalent not to exceed NC-35. The owner shall certify equipment and features are installed according to the approved plans.
(2) In new construction, the actual background noise at any student location within the classroom shall not exceed 45 dBA (Legx) and 70 dB (Leqx) (unweighted scale) where x is thirty seconds or more. The health officer shall determine compliance with this section when the ventilation system and the ventilation system's noise generating components, e.g., condenser, heat pump, etc., are in operation.
(3) Existing portable classrooms, constructed before January 1, 1990, moved from one site to another on the same school property or within the same school district are exempt from the requirements of this section if the portable classrooms meet the following:
(a) Noise abating or noise generating features shall not be altered in a manner that may increase noise levels;
(b) The portable classrooms were previously in use for general instruction;
(c) Ownership of the portable classrooms will remain the same; and
(d) The new site is in compliance with WAC 246-366-030(3).
(4) In new construction, the maximum ambient noise level in industrial arts, vocational agriculture and trade, and industrial classrooms shall not exceed 65 dBA when all fume and dust exhaust systems are operating.
(5) The maximum noise exposure for students in vocational education and music areas shall not exceed the levels specified in Table 1.
TABLE 1
MAXIMUM NOISE EXPOSURES PERMISSIBLE
Duration per day
(hours)
 
Sound Level
(dBA)
8
 
hours
 
85
 
6
 
hours
 
87
 
4
 
hours
 
90
 
3
 
hours
 
92
 
2
 
hours
 
95
 
1-1/2
 
hours
 
97
 
1
 
hour
 
100
 
1/2
 
hour
 
105
 
1/4
 
hour
 
110
 
Students shall not be exposed to sound levels equal to or greater than 115 dBA.
(6) Should the total noise exposure in vocational education and music areas exceed the levels specified in Table 1 of subsection (5) of this section, hearing protectors, e.g., ear plugs, muffs, etc., shall be provided to and used by the exposed students. Hearing protectors shall reduce student noise exposure to comply with the levels specified in Table 1 of subsection (5) of this section.
[Statutory Authority: RCW 43.20.050. WSR 92-02-019 (Order 225B), § 246-366-110, filed 12/23/91, effective 1/23/92; WSR 91-02-051 (Order 124B), recodified as § 246-366-110, filed 12/27/90, effective 1/31/91; WSR 89-20-026 (Order 333), § 248-64-320, filed 9/28/89, effective 10/29/89; Order 124, § 248-64-320, filed 3/18/76; Order 88, § 248-64-320, filed 10/3/73; Order 55, § 248-64-320, filed 6/8/71.]