Personal Safety, Protective Actions, and Decontamination Basics
PPE and respiratory protection
Chemical protective clothing is grouped into levels A through D. Level A is a fully encapsulating suit with SCBA or supplied air. Level B uses SCBA or supplied air with chemical-resistant clothing that is not fully encapsulating. Level C uses an air-purifying respirator with chemical-resistant clothing, permitted only when the contaminant and concentration are known and oxygen is at least 19.5 percent. Level D is a work uniform with no respiratory protection. Structural firefighting turnout gear provides thermal protection, not chemical protection, and it absorbs contaminants. Watch for heat stress and fatigue, and rotate personnel through rehab.
Protective actions
Work upwind, uphill, and upstream. Choose evacuation or shelter-in-place based on the product, weather, population, and time available, and use ERG isolation and protective action distances as a starting point, not a substitute for monitoring and judgment.
Decontamination
Set up decontamination before anyone enters. Emergency gross decontamination handles immediate life safety; technical decontamination uses a corridor with stations such as tool drop, gross wash, rinse, and bagging. Ambulatory and non-ambulatory victims are decontaminated separately. Decontaminate tools, equipment, and the decontamination workers themselves, and contain runoff.
Traps
- Selecting Level C for an unknown material or an unmeasured atmosphere.
- Believing turnout gear is chemical protection.
- Building the decontamination line after entry teams are committed.
- Forgetting that decontamination workers get contaminated too.
Rule of thumb
If you can smell it, taste it, or your eyes water, your respiratory protection has failed - back out and upgrade.