Battery gassing

[thinwater]

Offshore, we were regularly briefed on H2S, and its dangers and so on, but of course the most dangerous thing about it is perhaps when you no longer smell it, which could mean that it's dispersed, or that it's more concentrated and killed your sense of smell....

... on a rig, for obvious reasons considering the volumes involved, it was an extremely serious risk; colourless, odourless, heavier than air, explosive and corrosive. On a couple of rigs that I was on, facial hair was outlawed as it might interfere with the fitting of the BA set that one had to carry at all times....

Absolutely. the stuff is deadly, and in high concentrations it kills you sense of smell in a single breath. I recall just walking through a plume from a gathering tank vent on a catwalk and going from stink to nothing in one breath. I didn't stop and walked out of the other side of the plume in seconds, with no ill effect. But it was sobering. Past a certain point it does not get worse as it gets stronger, it just goes away. Two or three good breaths and you go away.

In case it was not obvious, the reason for the ban on facial hair in many refineries and on platforms is that you can't wear a respirator properly (leaks). If you are a contractor and show up with a beard they will hand you a prison razor and send you to the locker room. Hand soap, not Gillette Foamy.

 

[Refueler]

Absolutely. the stuff is deadly, and in high concentrations it kills you sense of smell in a single breath. I recall just walking through a plume from a gathering tank vent on a catwalk and going from stink to nothing in one breath. I didn't stop and walked out of the other side of the plume in seconds, with no ill effect. But it was sobering. Past a certain point it does not get worse as it gets stronger, it just goes away. Two or three good breaths and you go away.

In case it was not obvious, the reason for the ban on facial hair in many refineries and on platforms is that you can't wear a respirator properly (leaks). If you are a contractor and show up with a beard they will hand you a prison razor and send you to the locker room. Hand soap, not Gillette Foamy.

H2S does not need 'high concentrations' ... in fact its one of the lowest threshold limits of poisonous vapours ....

As one who has been into many Refineries / Terminals around the world incl USA - if you are in conflict with ANY rule on entering - you will just be refused and told to return once you have corrected the error.

 

[PaulRainbow]

Under normal charging batteries give off H2. If the battery is left on an absorption voltage (or the absorption voltage is too high) the battery will give off H2, possibly enough to set a Co alarm off.

If the battery voltage is excessive it will give off H2S (rotten egg smell). Most common cause for this is when two cells short together, effectively making the battery circa 10V. The charger will see this as a flat battery and will try to charge it at 14.4V or more.

Both of the above gases are explosive and H2S is toxic (as explained above). If the alarm goes off or you smell rotten eggs, turn all charges off (keeping away from the batteries) and keep away from them until the gas has had time to dissipate.

Here's what can happen if you create a spark near a gassing battery.

 

[Sandydog2]

H2S does not need 'high concentrations' ... in fact its one of the lowest threshold limits of poisonous vapours ....

As one who has been into many Refineries / Terminals around the world incl USA - if you are in conflict with ANY rule on entering - you will just be refused and told to return once you have corrected the error.

At high concentrations, it kills your sense of smell, as Thinwater says. I’ve worked with it too in industry. If the alarms were going off and you couldn’t smell it you needed to get out, fast.