Occupational Safety
Occupational Safety
This domain tests hazard identification and control for acute injury risks: machinery, electricity, falls, confined spaces, fire, lifting and vehicles. Expect hierarchy-of-controls decisions and practical safeguards, not just PPE lists.
Core rules
- Hierarchy: eliminate, substitute, engineering controls (guards, interlocks, ventilation), administrative controls (procedures, training, permit-to-work, LOTO), PPE last.
- Machinery: guarding at the point of operation, interlocks, emergency stops; lockout/tagout for maintenance with verification of zero energy. Consider stored energy: gravity, hydraulic, pneumatic, thermal.
- Work at height: avoid work at height; prevent falls by platforms and guardrails; arrest falls by harness only when prevention is not practicable. Scaffolds need competent erection and inspection.
- Confined spaces: hazard assessment, isolation, purging/ventilation, atmospheric testing before and during entry, standby person, rescue plan. A permit-to-work is a control, not a substitute for testing.
- Electrical: isolation, lockout, proving dead, earthing, residual current devices, competent persons.
Worked example
A conveyor jams during production. The operator wants to reach in while the motor is running because the stop button is nearby. Better: stop and isolate the conveyor, apply lockout/tagout, verify zero energy, clear the jam with tools, then restore guards and restart. A guard opening with an interlock is an engineering control; LOTO is administrative but essential for maintenance. PPE is not the primary control.
Traps
- Jumping to PPE before engineering controls.
- Lockout without verifying stored energy.
- Treating a permit-to-work as proof of safety.
- Forgetting contractors and cleaning staff in isolation.