Health, Safety, and Environmental Protection
Risk-based safety management
Health, Safety, and Environmental Protection tests whether you can identify hazards, evaluate risk, and select controls that reduce harm in a defensible order. Expect questions on the hierarchy of controls, exposure limits, lockout/tagout, and incident causation.
Core rules
- Apply the hierarchy of controls: elimination, substitution, engineering controls, administrative controls, then PPE. PPE is the last line, not the first choice.
- Risk = likelihood × severity; document the before-and-after rating and the basis for accepting residual risk.
- For airborne exposure, calculate the time-weighted average: TWA = Σ(CᵢTᵢ)/8 for an 8-hour shift, and compare with the applicable TWA and short-term limits.
- Isolate hazardous energy with lockout/tagout, verify zero energy, and control confined-space entry with testing, ventilation, an attendant, and a rescue plan.
- Investigate incidents for root causes, not just the immediate act; check design, training, supervision, and maintenance.
Worked example
A task is rated likelihood 4 and severity 4, giving risk 16 (high). Adding a fixed local exhaust hood reduces exposure likelihood to 2, but severity remains 3 because a release could still injure; residual risk = 6 (medium). The team documents the control, verifies hood capture velocity, sets exposure monitoring, and accepts the residual risk with a review date. Removing PPE alone would not have changed the likelihood rating; the engineering control did.
Traps
Starting with PPE; averaging exposures without time weighting; ignoring skin absorption or ingestion; and recording a residual risk as “low” without monitoring evidence.