PHMSA OK’s Use of DG Hazmat Rules for Highway, Rail Transport

Move Should Simplify Compliance for Sodium Ion Batteries

In a memo to the regulated community late last year, PHMSA made two important enforcement-related announcements for shippers of hazardous materials in 2025. The first part of the announcement will streamline regulatory compliance for shippers of hazardous materials by air or vessel. The second part provides flexibility for shippers of certain types of hazmat by highway or rail.  

Shipping by Hazmat Air and Vessel in 2025 (ICAO TI, IMDG Code) 

First, PHMSA announced that the agency will not take enforcement action against any person who offers or accepts hazardous materials for transportation in violation of US regulations if: 
 

• the shipment complies with the 2025-26 editions of the ICAO Technical Instructions or IMDG Code, and 
• all or part of the journey is by air or vessel. 

This part of the enforcement memo is typical from PHMSA. To facilitate international commerce and streamline compliance for stakeholders in the US, the agency allows shippers to use international rules like the ICAO Technical Instructions and the IMDG Code to prepare their shipments, as long as the consignment will travel by air or vessel or at least part of the trip. 

Most major air and cargo ship carriers require compliance with the international rules. Without this enforcement “break” from PHMSA, some shippers would be forced to follow the 49 CFR Hazardous Materials Regulations (HMR) to ship cargo to the airport, only to then re-label or re-package the cargo at the airport to comply with the ICAO TI. 

Using ICAO or IMDG for Highway or Rail Transportation

Later in the memo, PHMSA also says this: 

"In addition, for transport by rail and highway to, from, or within the United States, PHMSA will not take enforcement action against any offeror or carrier who offers or accepts hazardous materials identified and described on a shipping paper and/or packages marked and/or labeled in accordance with these standards—provided that appropriate emergency response information consistent with 49 CFR Part 172, Subpart G, accompanies the shipment." 

This new policy provides flexibility for shippers of hazardous materials that are newly regulated under the latest ICAO and/or IMDG regulations but are not yet regulated domestically—namely sodium ion batteries.



The current edition of the ICAO Technical Instructions, for example, includes dangerous goods list entries for sodium ion batteries—UN 3551 and UN 3552. These batteries are not yet regulated as hazardous materials in the US. Therefore, a shipper in the US who offers sodium batteries for transportation by air or vessel might run into confusion or shipping delays because they marked or labeled an "unregulated" product as hazmat. 

By clarifying that these batteries may be offered in line with the international standards, even when shipped by highway and rail, PHMSA hopes to simplify supply chain logistics for shippers of sodium batteries, stateside freight forwarders, and carriers, It should also improve supply chain safety overall, as shippers apply more stringent standards to a "non-hazmat" product.  

 

Tags: hazardous materials, international regulations, sodium ion batteries