Hydrogen Sulfide (H2S)

[gaschef]

Dear All

With reference to the discussion on H2S, and its effect on diving equipment. A few years ago whislt oil rig diving in the middle east, we went down on one well head survey, the first divers back using SCUBA reported a H2S type smell, as a result the remaining dives were conducted using SSDE with KM17 helmets.
At the end of the days diving all chome parts on the helmet were covered with a black deposit, when this was removed, we found 90% of the chrome had been eaten away.

This rig was a production platform (and had been for 10 years), not a drill rig so there was no corrosive drilling MUD around. THe Oil Company Manager of course assured us there was nothing untoward in the water!!!. THe Second day of diving saw a dive team clad in drysuits, gloves and anything else we could use to stop ourselves coming in contact with the beastie in the water.

I have never found out what the stuff was but have a suspiscion that it was gas perculating out of the substrata and mixing with normal sea bed mud,

AS a result I am always very wary of H2S, and stick to the old hands theory, if you can smell it get out quick. if not you will be there forever.

incidentally the safety officer wore his BA set the whole time he was on deck, and rumor had it that he slept with one in his bunk just in case

Just beware H2S is lethal stuff, if there is any hint its a recreational dive site, why bother diving it for fun, I would have to think twice about diving the site and I would be getting paid

Be interesting to hear from anyone else with similar stories


all the best

Tim "gaschef" Stevens





:bonk:

 

[pdoege]

Hello -

When I was growing up in the then small town of Oviedo, FL we had lots of "sulphur water" around. Couldn't get away from it.

Drank it, played in it, bathed in it.

Didn't like it but it was a fact of life. You could really smell it out in the celery and sod fields. It was the primary source of irrigation water.

I haven't smelled that smell in the water for a long time now. This is probably due to the huge population growth and the availability of purified/treated water.

This was in 1979, btw.

No harm done that I can tell

Peter Doege

 

[Rice]

the thing about sulphur gas is that it can be smelled at extremely low concentrations. I've been around laboratory concentrations and that stuff smells far stronger than you're describing.

I don't have first hand knowledge of these sources but I was told recentley that sulfur gas is more toxic than cynanide however you can smell it at suck low concentrations so it dosen't often sneak up on people.

And yeah, if you're around it alot you'll definetley stop smelling it at low concentrations.
HTH,
Rice