Sumps...

[netmage]

So, I was browsing thru the new CDS book, specifically a few articles about sumps, and I got to thinking.....

We're taught in cave training to assume any air pocket is suspect/foul...

Why is the same assumption not valid when traversing sumps....?

-Tim

[Sludge]

It's a different animal. When cave diving we're pretty much below the water table, so any air pocket has to be artificial. In sumps, this isn't the case.

[fixxervi6]

It's a different animal. When cave diving we're pretty much below the water table, so any air pocket has to be artificial. In sumps, this isn't the case.

Doesn't auto qualify all found air as breathable tho

Every any accidents recorded due to crossing a sump into bad air?

[sskasser]

I'll have to go dig around, but I'm pretty sure Farr's book mentioned some (or one?) incidents of bad air. I'm guessing most sump divers are pretty careful to self-monitor when breathing "new sump air" ...not perfect, but it is what it is.

[Arnold Mesiser]

A lot of sumps have constant oxygenation due to the flowing water etc there are certainly some bad air sumps though

[FW]

You are right, air quality is a issue. There has been a lot of discussion about taking air testing equipment into new sumps.

Generally, I keep the reg handy, until I give the air a sniff test. I have had problems though. One one trip, my buddy and I were both feeling funny and had to beat a hasty retreat back to our gear.

[Webmaster]

Usually in a sump when you surface it's in an actual passage segment rather than a bump in the ceiling. So a. you're dealing with a larger volume of air and b. hopefully it's a passage connected to more cave that has some sort of airflow at times. But you always need to be careful.

If I'm alone, I'll try to carefully smell the air and take a small breath then put my reg back in. If there's nothing foul and I feel ok I'll try to ease into it, keeping the reg in hand until I'm sure it's ok.

If two or more people, same thing more or less but you have someone close to watch you.

Even if it seems ok at first I monitor myself and others closely for a few minutes. I've run into enough bad air (never related to diving) before that elevated CO2 becomes obvious. That can take a few minutes before symptoms start to present though.