Personal Protective Equipment, Decontamination, and Worker Safety
This domain tests the worker’s last line of defense: respirator selection and care, protective clothing, the decontamination sequence, and hygiene. The exam expects you to know that PPE supports engineering controls and never replaces containment or HEPA filtration.
Respirators
- A medical evaluation is required before fit testing and use. Fit testing is annual, and a user seal check is performed each time the respirator is donned.
- Asbestos abatement requires HEPA particulate filters, not N95 filtering facepieces. Half-face air-purifying respirators have an OSHA assigned protection factor (APF) of 10; full-face APR APF is 50; a loose-fitting powered air-purifying respirator (PAPR) has an APF of 25.
- Select a respirator so that the expected exposure divided by the APF stays below the PEL. Facial hair at the sealing surface, missing fit tests, and damaged valves make the assigned protection unreliable.
- Clean and sanitize reusable respirators; store them so they are not contaminated. Replace HEPA cartridges when breathing resistance rises or according to the manufacturer’s schedule.
Clothing and decontamination
- Wear disposable coveralls with hood, boot covers, and gloves; tape seams. Avoid skin exposure and heat stress.
- Decon sequence: remove contaminated outer clothing in the dirty room, HEPA-vacuum the suit and boots, remove the respirator only after leaving the work area and passing through the shower, then shower before entering the clean room and putting on street clothes.
- No eating, drinking, smoking, or chewing in the regulated area. Wash hands and face before eating. Heat stress controls include fluids, rest breaks, and cooling.
Worked example
A worker’s measured exposure is 1.5 f/cc. A half-face APR has an APF of 10, so the estimated inside concentration is 0.15 f/cc, above the 0.1 f/cc PEL. Upgrading to a loose-fitting PAPR with APF 25 gives 1.5 ÷ 25 = 0.06 f/cc, below the PEL. A full-face APR with APF 50 would also be acceptable. The respirator change does not permit the crew to skip negative pressure or wet methods.
Traps that cost marks
- Choosing an N95 instead of a HEPA cartridge.
- Skipping the medical evaluation or annual fit test.
- Wearing a respirator over a beard at the sealing surface.
- Removing the respirator before showering, or showering with contaminated coveralls on.
- Assuming a higher-APF respirator makes containment optional.
- Ignoring heat stress because the worker is “just wearing a suit.”