Are OPDs required under DOT regulations?
The Hazardous Materials Regulations (HMR; 49 CFR Parts 171 – 180) do not contain specific design requirements for cylinder valves. We have not adopted the OPD requirements into the HMR. It is contained in the National Fire Protection Association’s publication “NFPA 58, Liquefied Petroleum Gas Code,” 1998 edition. NFPA is not a governmental agency; however, many states have adopted the NFPA Code as state law. You should contact your state or local government agency to find out if your state requires propane cylinders to conform to the OPD requirement.
