Washington permanent wildfire smoke rule (chapter WAC 296-820, effective 2024; supersedes the emergency WAC 296-62-085). Based on PM2.5 concentration; PM2.5 thresholds are canonical and did not change with the EPA 2024 AQI breakpoint revision.
Open Washington L&I / DOSH Wildfire Smoke Rule (WAC 296-820) in the interactive Guidance Wiki →
No standalone formula is published for this standard; see programmable logic and parameters below.
| PM2.5 | Respirator requirement |
|---|---|
| 19.5 µg/m³ | PM2.5 below Washington wildfire smoke training trigger (20.5 µg/m³). |
| 20.6 µg/m³ | Voluntary — PM2.5 ≥20.5 µg/m³ (training/notification + voluntary respirator) |
| 35.6 µg/m³ | Voluntary — PM2.5 ≥35.5 µg/m³ (mandatory exposure controls + voluntary N95) |
| 500.5 µg/m³ | Full RPP — PM2.5 ≥500.4 µg/m³ (mandatory full respiratory protection program) |
| 555.1 µg/m³ | Full RPP — PM2.5 ≥555.0 µg/m³ (mandatory respirator, APF ≥ 25) |
Wildfire smoke overlays are excluded from the work/rest composite and are never averaged with WBGT-based standards.
Required inputs: none
Optional inputs: pm25ugm3, aqiPm25, usStateCode, wildfireSmoke, outdoor