[Arkcon]

Is there a simple way to determine if a chamber, purged with argon, is really free from air, or it has a leak or another inadequacy?  A simple google search isn't helping me -- I get suggestions on how to insure the chamber is as inert as possible, I get reminders that I can never get a perfect chamber, etc.

What I'm interested is something like a pouch of chemicals, or a pile of some reagent.  Left out in the air for 4 hours it turns some dark color, sealed in an airless, well purged bag, it stays clear or turns a faint color, then in my chamber, it does one or the other, and I'd have an answer.  I'm not looking for a gauge to give me an answer to 4 decimal places, or to capture a sample for GC analysis.

It seems like there should be a simple Color reaction for oxygen, but I can't think of one.  Probably because I'd never observe it in real life.

[AWK]

Trace oxygen sensor?