Which standard addresses the integrity of compressed natural gas fuel containers?

The correct choice regarding the standard that addresses the integrity of compressed natural gas (CNG) fuel containers is 49 CFR 571.304. This standard is part of the Code of Federal Regulations that governs motor vehicle safety and includes specific requirements for the construction and performance of fuel containers used in vehicles.

The focus of this regulation is to ensure that the fuel systems, including the containers for CNG, are safe and can withstand various stresses and conditions that may occur during operation. This encompasses aspects like material integrity, pressure testing, and specific design criteria, all crucial to preventing leaks and ensuring the safe transportation of CNG.

In contrast, the other options pertain to various aspects of standards and practices related to gas and fuel systems. CGA S-1.1 focuses on gas cylinder safety, while ANSI/IAS PRD 1 and ANSI/CSA PRD 1b address pressure relief devices and related equipment, rather than the overall integrity of fuel containers themselves. Understanding the scope of each of these standards helps clarify why 49 CFR 571.304 is the appropriate choice for CNG fuel container integrity.