Which statement about FM class numbers is true?

• A. A higher number indicates greater protection across fire, impact, wind, and hail.
• B. A higher number indicates lower costs.
• C. A higher number indicates easier installation.
• D. A higher number has no relation to protection.

Answer: (A)

FM class numbers are a performance scale used by FM Approvals to indicate how a roofing product or system has been tested for protection in various conditions. As the class number goes up, the tested performance requirements become more stringent, meaning the material has demonstrated greater protection across criteria such as fire, impact, wind, and hail. This rating is about how well the product performs under designated tests, not about cost or installation ease, and there is a real link between a higher class and higher protection. So the statement that a higher number signifies greater protection is the best description of what the FM class number conveys.