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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Hazardous Materials: Requirements for UN Cylinders

Notice of proposed rulemaking.

PHMSA proposes to amend the Hazardous Materials Regulations (HMR) to adopt standards for the design, construction, maintenance and use of cylinders and multiple-element gas containers (MEGCs) based on the standards contained in the United Nations (UN) Recommendations on the Transport of Dangerous Goods. Aligning the HMR with the UN Recommendations will promote flexibility, permit the use of technological advances for the manufacture of pressure receptacles, provide for a broader selection of pressure receptacles, reduce the need for exemptions, and facilitate international commerce in the transportation of compressed gases.

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