Wildfire smoke is a separate occupational hazard from heat: it is tracked as its own smoke_overlay rule type and is never averaged into the heat work/rest composite. California's rule is AQI-for-PM2.5-canonical; Oregon's and Washington's rules are PM2.5-canonical (EPA revised its AQI breakpoints in 2024, so PM2.5 concentration is the stable denominator for those two rules).
| AQI | PM2.5 µg/m³ (24h avg) | Category |
|---|---|---|
| 0–50 | 0.0–9.0 | Good |
| 51–100 | 9.1–35.4 | Moderate |
| 101–150 | 35.5–55.4 | Unhealthy for Sensitive Groups |
| 151–200 | 55.5–125.4 | Unhealthy |
| 201–300 | 125.5–225.4 | Very Unhealthy |
| 301–500 | 225.5–325.4 | Hazardous |
PM2.5 columns are read live from FORMULAS.aqiToPm25() at each AQI band edge, not retyped — see EPA Air Quality System breakpoints (revised February 2024, 89 FR 16202).
California wildfire smoke protection regulation (Title 8 §5141.1). PM2.5-specific AQI standard for occupational wildfire smoke exposure. Canonical metric: Current AQI for PM2.5.
| AQI for PM2.5 | Respirator requirement |
|---|---|
| 150 | AQI for PM2.5 below Cal/OSHA §5141.1 trigger (151). |
| 151.1 | Voluntary — AQI for PM2.5 ≥151 (respirator voluntary) |
| 500.1 | Full RPP — AQI for PM2.5 above 500 (respirator mandatory) |
Wildfire smoke overlays are excluded from the work/rest composite and are never averaged with WBGT-based standards.
Oregon wildfire smoke protection rule (OAR 437-002-1081 / 437-004-9791). PM2.5 concentration is canonical; AQI equivalents shift with EPA breakpoints. Canonical metric: Ambient PM2.5 concentration (µg/m³).
| PM2.5 | Respirator requirement |
|---|---|
| 34.5 µg/m³ | PM2.5 below Oregon OSHA wildfire smoke training trigger (35.5 µg/m³). |
| 35.6 µg/m³ | Voluntary — PM2.5 ≥35.5 µg/m³ (training + voluntary respirator) |
| 201 µg/m³ | Mandatory FFR — PM2.5 ≥200.9 µg/m³ (mandatory filtering facepiece use) |
| 500.5 µg/m³ | Full RPP — PM2.5 ≥500.4 µg/m³ (full respiratory protection program) |
Wildfire smoke overlays are excluded from the work/rest composite and are never averaged with WBGT-based standards.
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. Canonical metric: PM2.5 concentration (µg/m³).
| 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.