That is a shame, hope he is ok.
You always have to be careful when mixing chemicals and sometimes chemicals will explode when you mix the wrong ones together.
If you are dealing with flammable mixtures and smoking that is not a good idea either.
The firefighters do not know what chemicals he was mixing or if he was smoking at the time but the accident will probably have impacts in that community like tighter regulations on chemicals or proper labeling on all containers (there should always be labels on all containers of chemicals at all times) in case there is an accident like this one so they know what they are dealing with and what precautions to take if it was worse.
Typically we don't use any flammable chemicals to clean houses, roofs, concrete, heavy equipment, trucks, buildings, etc.... Makes you wonder if he was dealing with flammable chemicals or if it was a reaction of mixing 2 different chemicals together that are not supposed to be mixed together.
Does anyone know this guy or if he is ok?