This SAE Recommended Practice provides guidance for the construction, operation, and maintenance of LNG powered heavy-duty vehicles and all LNG vehicles used for public transit or commercial applications.. The purpose of this document is to establish a uniform practice for construction, operation, and maintenance of LNG powered vehicles and is subject to change to keep pace with experience and technical advances. The revised Failure Modes and Effect Analysis (FMEA) which influences this document is a separate document, available in part as an informative appendix.