Solvent Fumes and Explosive Limits

Many of the hydrocarbon gasses are anaesthetic at these levels and you may pass out. In addition, some are toxic and can kill you. You can also be suffocated if there is no longer enough oxygen to support life, but this is an extreme case.

You should consider the density of the gas that leaks into the room. Some sink, and some float in air. Ceilings can get filled with light gasses, climb a ladder and fall off.

CO2 can fill basements, go down the stairs and never climb up.

Another thing, tanks of Kerosine/gasoline are very dangerous if you fall in, because you will sink in the light liquid right to the bottom. A 200 pouns man will feel a weight of about 40-50 pounds dragging him down. All such tanks have guides on the bottom, so close eyes, and follow the guide to the wall with your feet and a ladder will be there. Workers are trained in this and as long as you do not aspirate any hydrocarbons, you can get out.

With an oxygen plant I installed, we had a situation where birds would roost on the outlet, which was exhausting pure N2.

The area around frequently had dead birds. They had simply gone to sleep from oxygen starvation and never woke up.

Not the action of a solvent of course, but the action of most chemical vapors is similar - a displacement of oxygen.

There have been numerous cases where a worker entered an incompletely ventilated tank, passed out and his mate jumped in to save him, also passed out, etc. Usually the third or fourth worker wakes up and races off to get breathing apparatus or similar.

While many solvents are also toxic, O2 displacement will knock you out faster than the toxic effect. One lung full is normally enough.

The gases being within the flammable range has little bearing, unless it is right down near the lower flammability limit (you may then get enough O2 to realize something is wrong and get yourself out). You will certainly feel woozy, possibly also start to hallucinate, if the O2 is reduced but still enough to survive for a while.

The vapor itself will probably also make you nauseous.

If you break your safety lamp and it shorts while you are in there, you may leave considerably faster than you would like, although you have a good chance of being beyond caring by the time you are out.