Sidewall Zipper Failures

Injuries to tire installers and bystanders often occur during the inflation process when the sidewall of the tire bursts or explodes. The patterns of the rupture often resembles an open zipper - thus the phrase “sidewall zipper failure.”

Prior to inflation, there generally are no visual signs of stress in the sidewall and no outward indications that the tire may experience failure during normal servicing. The deflation of the tire (either in road operation or in a static condition) may, however, cause such stress and lead to a catastrophic blowout when the tire is reinflated. One particular United States manufacturer seems to have a higher incidence of zipper failures because of its sidewall design and manufacture, although the condition is also known to occur in the case of retreads (where the weakness in the sidewall went undetected during the retread operation).

Though zipper failures are a recognized risk in the tire industry, the response of the manufacturers has been to issue warnings, rather than to make tires less susceptible to the anticipated stresses. Even experienced tire repair people are victims of this problem.