A car owner pulls into a gas station for the repair of a flat tire caused by a nail. The nail is still in the tire.
The mechanic pulls the tire and begins to repair the puncture using a rasp-like tool, when suddenly the tire explodes.
The explosion is of such force that plaques are knocked off the wall in the waiting room of the gas station, windshields of cars parked nearby are shattered, and a car passing on an adjoining street is damaged.
The auto mechanic is severely injured.
It appears that the car owner got the flat temporarily fixed with a gas tire inflator. A gas tire inflator is one of those cans you can purchase in any store with a tube that screws into the tire valve and temporarily inflates a flat tire.
Unfortunately, the can contained a latex sealer and a highly flammable gas. It was intended as a temporary fix and the car owner did what anyone would do. He immediately went to the gas station for a permanent repair of the tire.
The theory is the mechanic's tool, which was made of metal, contacted the tire's steel belt causing a spark that ignited the gas. It turns out the inflated gas was a mixture of propane and isobutene. These gases are extremely flammable.
To avoid the dangers to yourself and anyone attempting to repair your tire, you should carefully read the label and avoid gas tire inflators with labels that state "Danger: Extremely Flammable."
There are nonflammable tire inflators. Unfortunately, most of these use an inflating gas containing CFC's which are being phased out because of environmental concerns. Brands that use a nonflammable gas called HCSE-22 may be the answer.
If you have used a gas tire inflator that does contain a flammable gas, you should immediately notify the mechanic before any repairs are made on your tire.
The mechanic should always remove the valve core (preferably outdoors and away from any potential source of flames, sparks, or excessive heat) and completely deflate the tire.