TIRE DEFECTS  
While trying to fixa flat, manytire workers and others can beblinded, maimed, or even decapitated when thetireexplodes. Most of these tires had been previously filled with a can of tire sealantto fix a leak in the tire. The propellant in the tire sealantoften times contains the butane & propane.When an ignition source is present a massive explosion is possible.
http://www.tiredefects.com/fix-a-flat/Default.htm  In United States