With reference to entry into enclosed spaces onboard, define “Enclosed space”, give examples, describe atmosphere testing checks and explain safety precautions prior to entry?
Short answer
- Definition: space with limited openings, inadequate ventilation, not designed for continuous occupancy
- Examples: cargo spaces, double bottoms, fuel/ballast tanks, pump-rooms, compressor rooms, cofferdams, chain lockers, void spaces, duct keels, inter-barrier spaces, boilers, engine crankcases, scavenge air receivers, sewage tanks
- Atmosphere test: calibrated portable instrument; O₂ 21% vol, flammable ≤1% LFL, toxic ≤50% OEL; test from outside at multiple levels; re-test if ventilation stops
- SOLAS XI-1/7: every ship carries atmosphere-testing instrument for O₂, flammable, H₂S, CO
- SOLAS III/19 §5 para 3.6: enclosed-space entry and rescue drills every two months
- ETO role: verify electrical isolation, ensure lighting/communication equipment is intrinsically safe, confirm gas detector calibration, maintain rescue gear readiness
Full answer
The full answer explains each point step by step, with the regulations and figures behind it and the discussion from other candidates. It is in the ETO section of the Marine One forum, open to members enrolled for the ETO exam.