Enclosed Space Casualty in No. 2 Double Bottom
During hold cleaning at anchor, the bosun sends a deckhand into the No. 2 double-bottom ballast tank to clear a blocked suction; the tank was not gas-tested and no permit was issued. Two minutes later the deckhand is at the bottom of the 5 m deep tank, slumped against the ladder, not responding to shouts. The bosun shouts to you, the nearest rating, to 'get down there and pull him out - quickly'. You see the tank hatch is open and the portable oxygen meter lying beside it reads 13.9% O2 when you press the sample button. The ship's rescue equipment and breathing apparatus are kept in the forepeak store, the accommodation ladder is 200 m away, and the master is on the bridge.
1. What do you do in the first minute, and why is the bosun's order wrong?
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Refuse the order, out loud and clearly, then raise the alarm. Say: 'No - no BA, no permit, meter reads 13.9% oxygen, I'd be a second casualty.'
Why the bosun is wrong: 13.9% O2 is well below the 19.5% minimum for entry. At that level judgement goes first, then consciousness within a minute or two, and the tank may also hold CO2, H2S or hydrocarbon gas from the ballast spaces. You have no breathing apparatus, no harness, no lifeline and no standby man. Entering would almost certainly produce a second body at the bottom of the tank - which is exactly how most enclosed-space fatalities multiply, as one would-be rescuer after another goes in after the first casualty.
Next: tell the bridge or master immediately, muster the rescue team, get the rescue kit and BA from the forepeak store, start ventilation of the tank if the fan is available, clear the hatch area, and stop anyone else going near it.
2. Set out the rescue you would carry out without entering the tank.
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Rescue from outside, using equipment and the ladder:
- Lower a rescue line with a bowline, or a rescue sling or harness, and try to get it over the casualty's arms or body; a boathook can help snag clothing or a harness.
- Rig the tripod or hatch davit over the opening if one can be brought. A manual vertical lift of an unconscious person 5 m up a ladder is not realistic.
- Keep talking to the casualty even if there is no response, and listen for breathing or groaning.
- Only a trained person in full BA, with harness, lifeline and a standby man at the hatch with a second set, may go down, and only after the atmosphere has been tested and the entry permit signed by the master. Two people at the top: one on the lifeline, one on the radio.
- Ventilate continuously and re-test before anyone goes near the bottom.
If the casualty is jammed on the ladder, use the line to take the weight off and pull from above rather than sending someone down.
3. Once the casualty is on deck, what are the first aid priorities and what communication must go out?
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First aid once on deck:
- Airway - check response, open the airway, look/listen/feel for breathing.
- Breathing - if not breathing, give two rescue breaths and start CPR at 30 compressions to 2 breaths, 100–120 per minute, and keep going; if breathing, place in the recovery position and give 100% oxygen by bag-valve mask.
- Circulation - feel for a pulse only to confirm, check for injuries from the fall, keep the casualty warm, give nothing by mouth, and never leave him alone.
Communication: tell the master and the bridge whether the casualty is breathing, and ask for radio medical advice (TMAS) with the oxygen reading, the time of collapse and the current condition; prepare the rescue boat or helicopter winch area. Write down the times - collapse, recovery from the tank, first breath, first compression - because the medical authority will ask for them. The tank is now a scene: nobody re-enters, and the master makes the reports.