Chlorine?
MY dad and I accidentaly made a chlorine bomb in our pool pump and it started reacting and exploding. We ended up trying to open the container with a stick from far away, all while breathing the fumes in. It got worse so we called the police for advice.
They sent firetrucks, police cars and ambulances to our house with the quickness. Fire Rescuse didnt want to touch it, so HAZMAT people got called in thier suits. They ended up throwing the canister in the pool and said dont go swimming for a week.
IT was a good day.