H2S Detection Tubes!

The H₂S safety training I went through today consists mostly of "practical" information, as it is intended for um, the "mechanical"/"industrial technician" type of audience, machine operators and such. Topics include things such as the properties of hydrogen sulfide, safety response in case of an accident, instructions on wearing a self-containing breathing apparatus, and using gas monitors. All quite straightforward, but I did find one thing really cool: H₂S detector tubes!

Obligatory picture:

These things are for determining the concentration of H₂S in air. Other tubes exist for detecting other gases, though they all generally work the same way.

Basically, the ampouled, calibrated glass tube contains a compound that changes colour in the presence of the analyte gas. To use it, break off both ends of the tube and insert it into a specialized pump (arrow points towards the pump). The pump can be a piston or a bellows, and is used to draw a specified amount of gaseous sample (e.g. 100 mL) through the tube; it also has a marker that tells us how long to wait for the reaction to be complete. Multiple draws of sample may be required depending on the tube. Finally, we simply read the concentration of the gas by looking at where the discolouration ends.

These things are cheaper than electronic monitors, and wrecking a tube is much cheaper than wrecking a sensor. (Wrecking the pump will cost alot more, though.) The error is pretty large, though, say ~25%, so it's more used for industrial safety checks than for analytical purposes.

What I like the most about the H₂S detection tubes is that they are filled with lead acetate! I want! (Sadly, I don't get to keep one. Boo.)

I also learnt a little bit of first aid (e.g. different types of rescue carries). A couple of fellow students were volunteered into being "victims"*; sadly, they are too heavy for me to lift. Erk. Things like the portable compressed air tanks with harness and regulator were heavy, too, but at least I can lift that. No glasses with face mask though - doesn't fit.

Oh, and apparently FeS is pyrophoric (with no form specified! Is it a fine powder? A chunk of pyrite? Storage conditions?). Without more details, I don't quite believe that.

*The "volunteers" were both male, and the instructor made them repeat the following:
Lord our father, let us protect our family jewels.
It took awhile for the "volunteers" to realize why. (I couldn't stop laughing for awhile when I heard that...lowbrow humour, I know.)

[Edited]
I spelled "tubes" wrong in the title. Erk.