We have three types of compressed gas here: nitrogen, nitrous oxide, and oxygen. We have a lot of them, clustered near Rig 1 (Rm 329), and Rig 2 (Rm 322).
There are actually three hazards you have to worry about with compressed gases.
The first is the contents of the cylinder. Oxygen is flammable, so don't use open flames. Nitrous, also known as laughing gas, is mildly anesthetic and can cause dizziness, sound distortion, and dissociation from reality. Nitrous smells sweet, but oxygen and nitrogen don't smell. If you open a couple of tanks in a closed room, you'll quickly drive out all the oxygen and asphyxiate yourself. (Or in the case of oxygen, you'll have a seizure and then go unconscious while the oxygen works on destroying your lungs.) You must be trained on how to prevent leaks before changing a tank. The only people allowed to change a nitrous oxide tank are Steve, Zoey and Daniel
Secondly, the tanks themselves are very heavy, the kind of heavy you don't want to drop on your foot. Get someone to teach you how to roll the tanks, and don't lean them at more than a 5% or so angle. Never ever lift them, and keep them secured behind a chain, strap, or cage at all times so that if they tip, they can't go far. If the tank isn't actively in use, the metal cap must be screwed on over the valve assembly.
The third hazard is the pressure of the gas itself. If for some reason the valve suddenly fails (like if the tank fell over and struck the bench), there is enough pressure to send the whole tank flying around the room, banging holes in the walls. Mythbusters did a bit on this and made a hole straight through a concrete wall. Needless to say, people are not as sturdy as concrete walls, so try not to get yourself in a situation where you could be in the way of one of these things.
Attached below is an inventory of all the tanks we have as of 3/9/2020. For questions, email firstname.lastname@example.org We no longer use Air Gas, only Middlesex Gas.