WASHINGTON, D.C. — The Pipeline and Hazardous Materials Safety Administration issued a notice of proposed rulemaking on Monday to update the Hazardous Materials Regulations by harmonizing them with international standards. The proposal aims to adopt international standards to reduce costs for entities within the United States and lower regulatory burdens on the U.S. economy.

The agency states that harmonizing domestic and international regulations will reduce delays and interruptions in transportation while maintaining current safety levels. The Pipeline and Hazardous Materials Safety Administration regulates nearly one million daily shipments of hazardous materials by land, sea, and air.

The proposal includes adopting the 24th revised edition of the United Nations Model Regulations, changes consistent with the 2027–28 edition of the International Civil Aviation Organization Technical Instructions, and Amendment 43-26 to the International Maritime Dangerous Goods Code. It also includes adopting the 2024 updates to Transport Canada’s Transportation of Dangerous Goods Regulations.

The Federal Hazardous Materials Transportation Law directs the Secretary of Transportation to ensure domestic regulations for the transportation of hazardous materials are generally consistent with the latest international regulations and standards, unless they are unnecessary or unsafe, or a more stringent safety standard is in the public interest. Comments on the proposed rule must be received within 60 days of publication in the Federal Register.

The docket number for the rulemaking is PHMSA-2025-0048 (HM-215S), the document number is 2026-21922, and the regulation identification number is RIN 2137-AF75. The proposed rule affects 49 CFR Parts 171, 172, 173, 175, 176, 178, and 180.