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Diver fainted

A member has reported an incident in which a diver fainted. The incident occurred when the diver arrived at the stage feeling very tired and requested permission to enter the bell without removing his chemical oversuit (barrier suit), (which was being worn due to potential seabed contamination). The dive supervisor subsequently approved this request. Shortly thereafter the diver fainted. He was assisted into his seat where he regained consciousness with the bell being flushed simultaneously.

The other divers in the bell displayed no visible symptoms of fatigue or contamination. The diver then had a drink of water and the bell was prepared for recovery. The bell was recovered under normal procedure as planned at the end of the dive. After mating to the chamber system all divers entered the sat complex as normal and without assistance.

Our member’s initial investigation noted the following:

  • Enhanced diving procedures had been discussed with the offshore team and the bells were dressed appropriately; . It became apparen’t that correct procedures had not been followed before and during the incident, particularly the requirements to wear the built in breathing systems (BIBS) and remove the chemical oversuit; . The enhanced diving procedural checklist had not been formally retained.

Despite there being a potential for contamination, the incident was considered “a straightforward episode of faint” and the result of a number of contributory factors such as:

  • Lack of food and drink;
  • Working hard in the water (tidal flow);
  • Balancing on the bell seat;
  • Relief of hydrostatic pressure;
  • Diver not removing his neck dam.

Our member identified the following lessons:

  • Need to enhanced diving procedures, contingency procedures, associated check lists and use of such procedures appropriately for the work site;
  • Need to review bell contamination exercise and carry out and record drills;
  • Need to review dive site assurance process;
  • Need to review method of storing and verifying diving operational checklists;
  • Need to review company guidance with respect to precautionary decompressing divers after medical or health issues.

Members may wish to refer to the following similar incidents (key words: diver, faint):

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