What standard must fiber reinforced plastic and hoop wrapped composite cylinders comply with?

Fiber reinforced plastic (FRP) and hoop wrapped composite cylinders must comply with DOT FRP2 standards. This standard is specifically designed to govern the manufacturing, testing, and performance requirements of these types of composite pressure vessels used for storing compressed gases like natural gas. The regulations under DOT FRP2 ensure that these cylinders have the necessary structural integrity and safety measures to handle high-pressure conditions, which is crucial for maintaining safety in transportation and storage.

DOT FRP1, FRP3, and FRP4 refer to other categories and specific types of composite cylinders with different design, performance, and testing criteria, which would not be applicable to fiber reinforced plastic and hoop wrapped composite cylinders. Therefore, understanding DOT FRP2 is essential for ensuring compliance and safety in the use of these specialized materials.