IMPORTANT:

1. The requirements in this section are in addition to the requirements found in other chapters:

a. Airborne contaminants, chapter 296-841 WAC.

b. Respirators, chapter 296-842 WAC.

1. (1) You must provide each employee with an appropriate respirator that complies with the requirements of this section, and require that employees use them in circumstances where exposure is above the permissible exposure limit (PEL), including any of the following circumstances:

   1. (a) Employees are in an exposure control area.
   2. (b) Feasible exposure controls are being put in place.
   3. (c) Where you determine that exposure controls are not feasible.
   4. (d) Feasible exposure controls do not reduce exposures to, or below, the PEL.
   5. (e) Emergencies.
2. (2) You must provide high-efficiency particulate air (HEPA) filters or N-, R-, or P-100 filters for powered air-purifying respirators (PAPRs) and negative-pressure air-purifying respirators.

3. (3) You must provide a powered air-purifying respirator (PAPR) to employees required to use respirators when:

   1. (a) The employee chooses to use this type of respirator or a licensed health care professional (LHCP) recommends this type of respirator in their written opinion; and
   2. (b) It will provide proper protection.

4. (4) You must follow these additional specifications for inorganic arsenic compounds with significant vapor pressure such as arsenic trichloride and arsenic phosphide:

   1. (a) Select front- or back-mounted gas masks equipped with HEPA filters and acid gas canisters or any full facepiece supplied-air respirator, when concentrations are at or below 500 mg/m³.
   2. (b) Select for powered air-purifying respirators (PAPRs) and negative-pressure air-purifying respirators equipped with HEPA (or equivalent) filters and acid gas cartridges when concentrations are at or below 100.

5. (5) You must prohibit the use of half-facepiece respirators for protection against arsenic trichloride. This is because arsenic trichloride is corrosive and rapidly absorbed through the skin.

   Note:

   When selecting air-purifying respirators for protection against inorganic arsenic, you'll need to consider whether other contaminants could be present at levels above permissible exposure limits and determine if a combination filter/gas-sorbent cartridge or canister is appropriate.

[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. WSR 18-22-116, § 296-848-40045, filed 11/6/18, effective 12/7/18; WSR 09-15-145, § 296-848-40045, filed 7/21/09, effective 9/1/09; WSR 07-05-072, § 296-848-40045, filed 2/20/07, effective 4/1/07; WSR 05-01-173, § 296-848-40045, filed 12/21/04, effective 5/1/05.]