The List of Hazardous Substances in 49 CFR hazardous materials will soon be gone. The requirements won’t change, but the list is being expunged from the hazardous material shipping regulations. Appendix A of the 172.101 Hazardous Materials Table will go from its current physical list to a reference, requiring shippers to defer to the 40 CFR 302.4 hazardous substance list.
A DOT hazardous substance is a material or hazardous waste listed in 40 CFR 302.4 as referenced in Appendix A to 172.101 in a quantity, in one package equaling or exceeding the reportable quantity (RQ).
It’s not that confusing. Appendix A is a clone, a copy. A cheap imitation of the 40 CFR 302.4 List of Hazardous Substances from the very start. So, a new final rule issued on August 4th, to reduce duplication and redundancy DOT will require shippers to access (through online services like e-regs websites) physically cross referencing the EPA 302.4 list, to ensure compliance with the identification, marking and documentation requirements when offering hazardous substances for transportation.
This does clear up one of the RQ compliance issues. Now, if a new reportable quantity is listed in the 40 CFR EPA regulations, it will instantly become an RQ under 49 CFR DOT shipping regulations. There was always a lag when there were changes to the 302.4 EPA regulations before DOT got around to finalizing changes in their Appendix A.
DOT requires you to identify reportable quantities, EPA requires you to report releases, neither of these requirements overlap. They will soon share the same list. Expect e-regs to update this new 49 CFR reference before December 2, 2026, the effective date.
Now you can see it, but soon you won’t.
Our current, 2025/2026 Hazardous Materials, Substances and Wastes Compliance Guide will be the last edition with the lists appearing in both Appendix A of the DOT regulations and in the 302.4 under the EPA regulations.
So, grab a copy before they also disappear.
Robert J. Keegan
Publisher and President
Hazardous Materials Publishing Company
Transportation Skills Program Inc
** If you are located in Hawaii, Alaska, or Puerto Rico, email us directly: lisa@hazmat-tsp.com with your order information (Name, Company, ship to, bill to, number of books) and please include a phone number to call you. Thank you!
PLEASE NOTE WE CANNOT SHIP TO P.O. BOX. Thank you!
The 2025/2026 Compliance guides with the Emergency Response Guidebook contain the most up-to-date mandatory regulations covering the activities of all HAZMAT/WASTE Employees and Employers engaged in any activity, taking place in any location involving hazardous materials, chemicals, substances, or wastes.
These are the only available Compliance Guides that provide all the critical interfacing DOT/EPA/OSHA Hazard Communication and Compliance requirements for Hazardous Materials, Chemicals, Substances, and Wastes.