I have been in a lab fire with Na-K alloy plus diethyl ether, which was not fun, nor especially my fault, although I did put that one out and hit the alarm.That evacuated an entire building, putting my future wife out in the rain. We met that night where I had to explain that she got soaked because of me.
Once my students managed to evacuate a wing of a school when one ignored the instructions making copper sulphate via sulphuric and copper oxide, heating unneutralised acid to form acidic plumes. Think that was my third week in that school.
I once dunked a bit of sodium accudentally- it hit the ceiling with a huge bang, making a girl in the front scream and possibly wet herself. I have had a couple of ethanol fires, again due to potassium, evacuating the school but only as a precaution you understand, and burned a hole through two heatproof mats into a wooden bench with charcoal blocks used in the extraction of lead from lead oxide. The mark is still there, and nowadays we use five mats.
During my A levels I got concerned sulphuric on my trousers and shirt leading to a rapid removal of clothes as it ate through them. Also threw away some phosphorous chloride down the sink which is not to be recommended.
When working for Mobil I saw a heated bitumen canister lose its lid and fly across the room into the wall, that was my bad, not putting holes in the canister first.
I have seen Lithium Aluminium Hydride go up from a washing up bowl, which really should not happen. Had a few halogens go haywire.
I won't mention chlorate bombs.....
Strangely despite all this and more I ended up being my school's health and safety officer....