I've been locating possible storm drain exploration sites and some mysterious holes and doors in the ground. I've also researched a few oxygen detectors but I'm hoping someone who owns one or is more experienced will have an affordable one they recommend that would help keep me safe from dangerous gasses and particulates in which a respirator won't save me.

your lungs

if you cant breathe then there is no oxygen
if you pass out then there are dangerous gasses

Posted by Thecurious I've been locating possible storm drain exploration sites and some mysterious holes and doors in the ground. I've also researched a few oxygen detectors but I'm hoping someone who owns one or is more experienced will have an affordable one they recommend that would help keep me safe from dangerous gasses and particulates in which a respirator won't save me.

I won't recommend a specific meter. Your research should lead you to the correct choice. That said, I strongly recommend a four gas meter (Oxygen (O2), Carbon Monoxide (CO), Hydrogen Sulfide (H2S), and Combustible Gases (LEL))

Some of the folks I know will tie a line to their meter and let it dangle a few feet below them as they descend into unknown confined areas. If the alarm goes off, they stop descending and climb back out. I explore underground mines and have never had mine go off. Friend have told me of low O2 warnings, but never any of the other gasses.

Every now and then I have read of trained professionals losing their lives in confined spaces.

Abby Normal

Alright thanks a lot. I may just be too worried about it but after hearing some of the stories about people who come in contact with "dead air" and gasses such as hydrogen sulfide, I can't help but be cautious. I don't have many mines in my near vicinity but even storm drains and weird rusted out tunnels could harbor some harmful gasses. I'll look into that four gas meter, thanks again.

A friend you don't like to walk 20 meters ahead of you.

For 99% of storm drains a gas meter is completely unnecessary. The only time you should be worried about bad air in drains is when there's a thick layer of organic matter (dead leaves/grass) trapped in mud- if your footprints bubble or you start to smell rotten eggs, turn around and go towards safer air. But most drains will have either clear flowing water, gravel, or dry floor- none of which are problematic.

Now sewers on the other hand, are chock full of decaying organic matter that can create sewer gas. You should absolutely have a gas meter when running sewers. Of course, I'm from the midwest where nobody does that and instead relies on the ol' "leave if you feel yourself dying" method, but don't mess around with sewers until you're more experienced with storm drains. Just to be safe, double check whether the city you're exploring in has separate wastewater and stormwater systems because some cities combine them and some separate them.

Oh yeah, and when it rains no drains. Don't fear the air, fear the weather.

Posted by Aran For 99% of storm drains a gas meter is completely unnecessary. The only time you should be worried about bad air in drains is when there's a thick layer of organic matter (dead leaves/grass) trapped in mud- if your footprints bubble or you start to smell rotten eggs, turn around and go towards safer air. But most drains will have either clear flowing water, gravel, or dry floor- none of which are problematic. Now sewers on the other hand, are chock full of decaying organic matter that can create sewer gas. You should absolutely have a gas meter when running sewers. Of course, I'm from the midwest where nobody does that and instead relies on the ol' "leave if you feel yourself dying" method, but don't mess around with sewers until you're more experienced with storm drains. Just to be safe, double check whether the city you're exploring in has separate wastewater and stormwater systems because some cities combine them and some separate them. Oh yeah, and when it rains no drains. Don't fear the air, fear the weather.

I was near the outside of a gated off storm drain with two friends the other night and there was about a foot of snow and no way for me to get in unless I twisted off the bolts. Anyway I smell the rotten egg smell you mentioned and I asked which of my friends farted to which they said they didn't(they're the type who doesn't really care and they would just be upfront). I don't know why that smell would've came from the drain but now after you say some sewers and storm drains are combined, though the entrance we found was in a detention basic which wouldn't make too much sense, but now I know for future reference. I'll refrain from buying one until I find something I'm more confident will have harmful air. Thanks.