Two men down in a hold of direct reduced iron

Stop him, physically if necessary. A dust mask gives him no protection whatsoever against the hazard in that hold, and he will become the third casualty at the bottom of the ladder. This is the classic enclosed space multiple fatality: the would-be rescuer is the second death.

The hazard. DRI oxidises slowly and consumes oxygen; it can also evolve hydrogen, which is explosive from about 4% upwards, and generates fine dust. A hold sealed for four days is exactly where an oxygen-depleted, possibly hydrogen-bearing atmosphere should be expected. DRI cargoes are also prone to self-heating. A dust mask filters particles; it supplies no oxygen.

First five minutes.

1. Raise the general alarm, inform the master and the bridge, and stop the third seaman from entering. Post a man at the hatch to prevent anyone else going down.
2. Muster the rescue team; the master takes charge. Note the time of the alarm and the last known movement of the casualties.
3. Test the atmosphere from the deck with an extension probe at several levels - oxygen, hydrogen/flammable gas, carbon monoxide - before anyone opens the hatch further. Record the readings and the time.
4. Only a properly equipped team enters: self-contained breathing apparatus, rescue harness and lifeline, a tripod and winch, a standby man at the hatch, and communications. Two entrants minimum, with a third man at the coaming. No entry on a filter mask, ever.
5. Start forced ventilation, but be alert to the hydrogen and dust - no ignition sources, bonded and earthed equipment, no smoking, and no hot work anywhere near No. 3.
6. Treat it as a fire-and-rescue standby as well: lay out a hose, brief the engine room to be ready, and have the ship's medic and first aid party standing by at the hatch with oxygen and the defibrillator.

If BA is not immediately available, the honest answer is that entry must wait. A body is not a reason for a third death.

Bosun - cardiac arrest from hypoxia.

1. Confirm unresponsiveness, no breathing and no pulse (no more than 10 seconds), then start CPR at 30 compressions to 2 ventilations, with compressions about 100–120 per minute and a depth of one third of chest depth.
2. Ventilate with a bag-valve mask on high-flow oxygen - this is a hypoxic arrest, so oxygenation and good compressions are what give him a chance.
3. Attach the AED as soon as it arrives, follow its prompts, and continue CPR. Do not stop to reassess unless there are signs of life or the AED tells you to.
4. Consider the mechanism: he may have fallen 9 m. If there is a possibility of spinal injury this does not change CPR - you cannot resuscitate a spine.
5. Rotate the compressor every two minutes; fatigue produces shallow compressions.

AB - breathing but hypoxic and confused.

• High-flow oxygen by mask, sitting up if his breathing allows.
• Continuous monitoring of breathing, pulse, consciousness and skin colour. Be ready to assist ventilation.
• Treat for the fall as well: check the head, neck and back, look for other injuries, and if a spinal injury is suspected keep the head aligned and immobilise before moving him.
• Do not give food or drink; keep him warm and reassured, and keep someone with him at all times.

Both. Record the times of collapse, recovery, first breath, first compression; keep the hold closed and secure; treat the space as still hazardous and keep everyone out until it has been ventilated and re-tested. The medical advice is then sought while treatment continues, not instead of it.

Getting advice. The master (or the radio officer) sends a distress/urgency priority alert on the GMDSS: VHF DSC or HF DSC to the nearest Rescue Coordination Centre, or an Inmarsat call using the special access code for medical advice through a shore earth station, with the ship's position, course and speed, the number of casualties, their condition, the treatment given so far and the assistance required. The offshore terminal on VHF is worth calling in parallel - a 60 nm helicopter is a far better asset than a 10-hour passage, and the terminal's own medic may be closer to the scene. Use the Telemedical Maritime Assistance Service through the RCC if available; shore doctors can direct treatment and confirm whether the casualty must be moved.

The decision. It is the master's, taking advice, and it turns on:

• Time to definitive care. A hypoxic cardiac arrest after prolonged immersion in a depleted hold has a very poor prognosis. If there is any return of circulation, the helicopter is clearly right; if there is none after prolonged resuscitation, the master must weigh the risk to the helicopter crew against a rescue that may not save the casualty.
• Recovery conditions. A 1.5 m swell and a dark hold are not ideal for winching. Winching needs a clear deck area, the ship's course and speed adjusted to make a lee, deck lighting, no obstructions and, ideally, daylight - it is now mid-morning, which helps.
• The second casualty is breathing but confused: he is more likely to survive a 10-hour passage than a cardiac arrest, but he still needs oxygen, monitoring and, probably, hospital care.
• The ship. Deviation towards the terminal costs time and fuel; the remaining DRI cargo has to be monitored (hydrogen, self-heating) and No. 3 made secure before any helicopter operation, because the hatch cannot stay open.

Decision. Request the helicopter for the bosun and continue CPR on deck; keep the AB on oxygen and plan to land him ashore for assessment. Advise the company, the agent, immigration and the port authority, and record every clinical time and every message.