WAC 296-56-60055. Carbon monoxide

(1) The carbon monoxide content of the atmosphere in a room, building, vehicle, railcar or any enclosed space must be maintained below 50 parts per million (0.005%) as an eight-hour average area level. Employees must be removed from the enclosed space if the carbon monoxide concentration exceeds 100 parts per million (0.01%). (2) Employers must conduct tests to determine carbon monoxide concentration whenever necessary to ensure that employee exposure does not exceed the limits specified in subsection (1) of this section. (3) Employers must make sure tests for carbon monoxide concentration are made by designated persons using gas detector tube units certified by NIOSH under 30 C.F.R. Part 11 or other measuring instruments whose accuracy is as great or greater. (4) Employers must make available a record of the date, time, location and result of carbon monoxide tests for at least 30 days.