Ozone cracking

Ozone Cracking
A vehicle tire showing signs of ozone cracking
A vehicle tire showing signs of ozone cracking
Ozone cracking in natural rubber tubing
Ozone cracking in natural rubber tubing

Cracks can be formed in many different elastomers by ozone attack, and the characteristic form of attack of vulnerable rubbers is known as ozone cracking. The problem was formerly very common, especially in tires, but is now rarely seen in those products owing to preventive measures.

However, it does occur in many other safety-critical items such as fuel lines and rubber seals, such as gaskets and O-rings, where ozone attack is considered unlikely. Only a trace amount of the gas is needed to initiate cracking, and so these items can also succumb to the problem.