State the hazards and precautions for enclosed space entry, sketch and describe an oxygen analyser, and give ISM instructions to entrants?
Short answer
| Aspect | Key Points |
|---|---|
| Hazards | Oxygen-deficient, H₂S, CO, flammable vapours |
| Precautions | Risk assessment, permit, isolation, ventilation, testing, attendant, rescue gear |
| O₂ analyser | Electrochemical, calibrated, multi-level sampling |
| ISM instructions | Toolbox talk, PPE, communication, evacuate if unsafe |
| ETO checks | Electrical isolation, instrument calibration, comms |
- Hazards: oxygen-deficient atmosphere, toxic gases (H₂S, CO, cargo vapours), flammable vapours
- Precautions: risk assessment, permit to work, isolation, continuous ventilation, atmosphere testing at multiple levels, attendant at entrance, rescue equipment ready
- Oxygen analyser: portable electrochemical sensor, calibrated before use, samples at top/middle/bottom
- ISM instructions: toolbox talk, understand permit, wear PPE and harness/lifeline, maintain communication, evacuate if unsafe
- Requirements: SOLAS XI-1/7, A.1050(27), MS Act 2025 s.147, IACS UR F7, ISM Code §1.2.2, MSC.1/Circ.1477
- ETO role: ensure electrical isolation, verify instrument calibration, confirm communication equipment
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.