Front steering tires on an apparatus should have a minimum tread depth of which measurement?

• A. 6/32 of an inch
• B. 4/32 of an inch
• C. 2/32 of an inch
• D. 1/32 of an inch

Answer: (B)

The minimum tread depth for front steering tires is four thirty-seconds of an inch. This level gives enough grip for effective steering and braking and helps pull water away from the contact patch to reduce hydroplaning risk. When tread wear reaches two thirty-seconds or one thirty-second, traction and steering feel degrade, increasing stopping distances and the chance of loss of control, especially in wet or aggressive driving conditions common in emergencies. Deeper tread, like six thirty-seconds, would still meet the requirement, but the standard establishes four thirty-seconds as the minimum. Use a tread depth gauge and check multiple grooves to ensure this minimum is maintained.