When I was a kid with quarries in the area we often heard and felt blasting at home and at school. In the mid '80's I worked near a scrap metal smelter, sometime there would be a huge blast that would make the whole wall of our building move. Most of the workers there were my customers, and one day I asked what the explosions were - he laughed and said ''aerosol can''...they leave one in for a bit of fun. One night I went to drop in at work and the whole area was cordoned off - there was an oxy bottle in the mix, and it nearly destroyed the building.