Drysuit Hazard

[OutlawCaver]

A recent fatality of a public service diver has made me stop and think about this.

He was floating behind a boat without diver gear donned in about 20ffw. His neckseal tore and the suit flooded instantly sending him to the bottom of the near zero viz river. I have often floated out into deep water in a sink before or after a dive. I will certainly be aware of this possibility in the future. Just something to think about.

[newman_diver]

When they trialed our new suits (trilam) for work they tested the buoyancy with the zipper wide open to simulate a flood. Didn't sink.

I wonder if there are any other factors involved (wearing a weight belt, ankle weights, type of undergarment, etc) that may have contributed to this.

[bletso]

Just think a minute. They found him floating. It seems to me he certainly didn't sink.

Dale

[Sludge]

Read it again.

[bletso]

yup, sounds like a panic attack. Ditched his gear and floated up, or did I miss something?


Dale

[FW]

yup, sounds like a panic attack. Ditched his gear and floated up, or did I miss something?


Dale

It was the other way around, He started out floating, tore the neck seal, than sank.

[Gene_Hobbs]

You might also find this article of interest:

Barsky SM, Heine JN. Observations on flooded dry suit buoyancy characteristics. In: Proceedings of the DCIEM Diver Thermal Protection Workshop, Defence and Civil Institute of Environmental Medicine, Toronto, CA, 31 Jan-2 Feb 1989. Edited by RY Nishi, Workshop Chairmen TT Romet and JA Sterba. RRR ID: 3922

Military and scientific divers have increasingly turned to dry suits for thermal protection in cold water and ice diving. Concurrent with this increase comes a concern for proper training procedures, underwear requirements, and safe configuration of the diving system. One area of common concern among all dry suit divers is the residual buoyancy available, or not available, in the event of a catastrophic dry suit failure. This issue must be considered due to the persistent use of dry suits as buoyancy compensators by many dry suit divers. This paper examines dry suit buoyancy under simulated failure conditions with a variety of suit/underwear combinations. Of the 13 combinations tested, after complete flooding and removal of the diver's lead weights, 2 systems remained positively buoyant while the other systems eventually all became negatively buoyant. Recommendations are given for equipment requirements, training, and emergency procedures for dry suit usage.

[OutlawCaver]

I am sure that under garments were involved. I had a catastrophic failure of a boot on a trilam suit with heavy undergarments back in the late 80s in Sullivan Sink. I was extremely negative and very cold getting out of that cave.

[sskasser]

This was eye-opening! Thanks for the heads up, Vince, and thanks, Gene, for the follow-up data.

[Webmaster]

That would be something to test. Buoyancy with shell and compressed neoprene suits with different types of undergarments. I suspect you might see a significant difference.

Marbry