To correct confusion about the out-of-service status regarding dual wheels, the Commercial Vehicle Safety Alliance (CVSA) has issued a clarification for that section of its training bulletin.
Items 10 b (2), 10 b (3), and 10 b (7) contain notes indicating the out-of-service condition applies for a single tire when one tire meets the condition, and on dual wheels when both tires meet the condition. According to the CVSA Vehicle Committee, if both tires in a dual wheel set meet any combination of the out-of-service conditions under 10 b (2), 10 b (3), or 10 b (7), then both tires are to be placed out of service.
For example, if one tire in a dual wheel set has an exposed area of the top ply exceeding two square inches and the other tire has less than 1/32" tread when measured in any two adjacent major tread grooves at three separate locations on the tire, then both tires would be out of service.