Overview: A tire blowout occurs after the mechanical failure of the tire or rim assembly at pressures typically around 145 psi. Tires exposed to heat may undergo the process described below and violently explode.
Explosive Process: There are three (3) phases leading to a tire explosion:
1. Air pressure inside the tire will rise from 90 to 235 psi as temperatures rise.
2. At approximately 365⁰ Fahrenheit, the rubber undergoes a runaway exothermic reaction, releasing flammable gases that increase pressure within the tire. This reaction can continue even if an exterior fire is extinguished.
3. An explosion will occur when the tire contains at least 5.5 percent oxygen, and the flammable gases reach their lower explosive limit and auto-ignition temperature. The explosion may generate shock waves and pressures over 1000 psi.
NOTE: this explosive force is generated from tires inflated with ambient air regardless of the rim assembly present on the vehicle.