Unintentional release of diving helmet – neck dam/helmet securing arrangements
A member reported two incidents in which there has been unintentional release between neck ring and helmet on a KM17C diving helmet during saturation diving operations. Members are encouraged to ensure that diving personnel are aware and that they check the interface between helmet and its securing arrangement towards other equipment supporting the diver. Working conditions could also give same results, e.g. working close to (taut) wires or large insertion bolts, etc.
Our member identified the following corrective actions:
- Verify that interface between helmet and other diving equipment is such that it cannot hook up the release mechanism;
- Be aware of the potential of release such that operational measures could be taken to prevent this;
- Report any further problems (with helmet and locking mechanisms) immediately.

The manufacturer has developed a pull pin sleeve, which may also work to prevent this from recurring. See the Kirby Morgan website for more details: kirbymorgan.com/support/bulletins/2012/bulletin-07-2012.
A series of photographs follows for illustrative purposes:






Safety Event
Published: 2 August 2016
Download: IMCA SF 20/16
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