US PHMSA Proposes Hazardous Materials Transport Updates

The US Pipeline and Hazardous Materials Safety Administration (PHMSA) has proposed changes to hazardous materials transport rules to align them with international standards. The HM-215S notice, published on 27 October 2026, sets a comment deadline of 28 December 2026.

The proposal covers shipping descriptions, hazard classes, packing groups, special provisions and packaging authorisations. It also addresses quantity limits for air transport and vessel stowage requirements. These are proposed amendments, rather than a final rule taking effect now.

Changes To Chemical Entries And Packaging

PHMSA proposes adding a Packing Group II entry for butyl acrylates. Its explanation cites the flash point of tert-butyl acrylate and the existing entry’s Packing Group III designation. The proposal also distinguishes vanadium pentoxide in non-fused form containing at least 10% respirable particles from material remaining in Packing Group III.

Harmonisation would not extend to every international change. PHMSA is not proposing to adopt provisions allowing recycled plastics in intermediate bulk containers. The agency says oversight remains necessary to ensure the safety of containers made from recycled material.

How The Proposal Fits The Existing Framework

The notice’s background section explains that UN Model Regulations are updated every two years and underpin national and international transport rules. PHMSA routinely updates the US Hazardous Materials Regulations through rulemaking to incorporate relevant changes, while considering whether individual provisions are appropriate for US adoption.

Comments on this proposal should identify docket PHMSA-2025-0048 (HM-215S). The notice provides electronic submission through Regulations.gov and alternative submission methods.