WAC 296-36-145
Regulation of pressure and air quality in
working areas -- Air quality in working areas. (1) Ventilation. An automatic air quality monitoring system acceptable to the
director, department of labor and industries, shall be installed
in the pressurized working chamber and shall at all times be
maintained in proper working condition. The system shall provide
continuous sampling and monitoring of the air and shall indicate
by visual and audible alarm the presence of dangerous air
contaminants in excess of the following:
| Carbon monoxide |
0.01% |
100 ppm |
| Carbon dioxide |
0.50% |
5000 ppm |
| Oxides of nitrogen |
0.0005% |
5 ppm |
| Methane |
0.25% |
2500 ppm |
| Hydrogen sulphide |
0.002% |
20 ppm |
The director in his discretion may change these
concentrations to conform with good practices as recommended by
the American Conference of Governmental Industrial Hygienists.
The system shall also indicate and give alarm at any time
the oxygen content is less than 19.5 percent.
The system shall be so arranged that the visual and audible
alarm will give warning in the working chamber and at the lock
tender's station at the low pressure side of the locks.
In addition to the specific requirements contained in these
standards of safety chapter 296-62 WAC shall apply for rock dust
and ventilation.
(2) Protection against atmospheric containments: The
requirements of chapters 296-62 and 296-155 WAC, Part Q shall
apply.
[Statutory Authority: Chapter 49.17 RCW. 90-17-051 (Order
90-10), § 296-36-145, filed 8/13/90, effective 9/24/90; Rules
(Part VII C), filed 12/28/62; § 25, filed 3/23/60.]