Gas testing & enclosed space: what SIRE 2.0 inspectors ask and find
Gas detectors, calibration records, span gas and enclosed space entry procedures are checked closely, along with how the crew uses them.
Do this before the inspector arrives: Check gas meter calibration and span gas dates.
What the inspector wants to see
- Gas meter calibration and bump-test records, span gas in date
- Enclosed space entry permits and procedure
- Detector alarm settings
Questions inspectors ask about Gas testing & enclosed space
Does the SMS cover spaces that are not classed as enclosed spaces?
Inspectors asked to see the procedure covering such spaces.
Which IMO resolution requires CO2 measurement before enclosed space entry?
MSC.581(110), effective 3 December 2025. Inspectors asked for the company procedure and the enclosed space register.
The entry permit sets benzene and H2S evacuation at 50% of 1 ppm. How will you measure that?
Inspectors expect you to show equipment that can actually detect that low level (0.5 ppm), as the permit demands.
What is required for entry into the N2 generator room?
An entry procedure and an O2 meter at both entrances (a CDI requirement). Atmosphere results and entry/exit times should be recorded.
How is a portable gas meter calibrated and bump-tested, and how are its alarms set?
An engineer was asked to explain calibration, alarm and pre-alarm settings, and how to carry out a bump test. All officers should know this.
Your multi-gas meter hose is 15 m but the tank is 20 m deep. Can you still sample?
Per the GX-6000 maker, yes: increase the sampling time to 90 seconds or more and a 20 m hose can be used.
There are 27 Gas testing & enclosed space questions in NilObs, with spaced repetition so the ones you miss come back. Practise them free.
Real Gas testing & enclosed space observations, and how to avoid them
Interviewee did not know the portable gas detectors used for entry permits could not sample the full depth of the cargo tanks and pump room.
Avoid it: Know your gas detector's sampling hose limits and confirm they reach the bottom of each space before entry.
Per the maker's manual, the three portable gas detectors could only sample to 50 ft, while the cargo tanks and pump room were about 20 m deep.
Avoid it: Match sampling hose length and pump capacity to the deepest space on board and order extensions if needed.
Same issue recorded again: entry-permit gas detectors had a 50 ft sampling limit against cargo tank and pump room depths of about 20 m.
Avoid it: Verify detector capability against space depth whenever gas testing equipment or permits are reviewed.
A crankcase inspection with web deflections had been carried out, but no enclosed space entry permit was raised for it.
Avoid it: Treat crankcase entry as enclosed space entry: ventilate, test the atmosphere and raise a permit.
The fixed flammable gas detection system for ballast tanks and accommodation entrances was defective; logged, acknowledged by shore and class informed.
Avoid it: Know the interim measures, such as portable gas checks, while fixed gas detection is out of service.
Company procedure did not define spare parts or calibration gas quantities for gas detectors, only saying 'sufficient'.
Avoid it: Keep an inventory of calibration gases and spares with minimum stock levels and expiry dates.
The ballast pump room housed a nitrogen buffer tank, but its low oxygen alarm sounded only in the CCR, not locally in the space.
Avoid it: Test low-oxygen alarms both locally and remotely for any space containing nitrogen equipment.
There was no local oxygen readout at the entrance to the ballast pump room, although the space held a nitrogen buffer tank.
Avoid it: Check oxygen levels before entering any space with nitrogen equipment, using a portable meter if needed.
Who answers for Gas testing & enclosed space
Chief Officer, Third Officer, Pumpman, HSEQ Manager, Training Officer. NilObs picks the questions and the daily drill for your role.
Rehearse Gas testing & enclosed space before your next inspection.
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