Final answer:
To evaluate tire sidewall condition, a tool with visual aids is used to compare the cracking on the tire's sidewall to provided pictures, determining if the tire is safe or needs replacement.
Step-by-step explanation:
When evaluating the condition of a tire's sidewall due to ozone or weather-related cracking, one would use a specific tool designed for this purpose. This tool often has visual aids to help determine the severity of the sidewall damage. The user places this tool against the tire's sidewall and matches the visible cracking with the pictures provided on the tool to assess the tire's condition. This analysis is crucial as it can indicate whether the tire is still safe to use or if it requires replacement to avoid potential safety issues on the road.