Question - Gas detector for ironstone mine exploration

[The Lone Ranger]

One thing I'll add is always turn on your gas meter before you head down a mine, away from the entrance and in clean air. All gas meters go through a self-calibration sequence when you turn it on.

You may have a top of the range 4 gas monitor, but if you turn it on when there is already gasses present it will give you false readings, there have been fatalities in industrial situations due to the workers turning the gas monitor on once they reach the work location to comply with the permit to work, then believe there wasn't an issue as the gas meter did not alarm. They died blissfully unaware of the hazardous atmosphere around them thinking they were safe.

 

[crashed.out]

Thank you @cunningcorgi @Ojay & @pirate - you've taught me something I ought to have known / figured out. Refreshing to see a community that informs and assists rather than denigrates and insults

 

[marcman]

Thank you all for the further replies.

The info on atmospheric pressure is very useful and something I had already thought about. I have purchased a barometer iPhone app that seems to work well. Evidently, this week would not have been a good one for exploring.

@crashed.out - your information regarding checking at floor level as well as eye level is gold, and something I probably would not have considered. Also thanks for pointing out that a 4-gas does not monitor CO2. I'm now hunting around for a reasonably priced CO2 monitor. Also not yet decided between the single gas, 2yr O2 monitors, or a 4-gas. Not rushing it yet, as won't be back to exploring for a couple of weeks,