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United States Department of Transportation United States Department of Transportation

Hazardous Materials Information Center

1-800-HMR-4922
1-800-467-4922
202-366-4488
infocntr@dot.gov

Have a question about transporting hazardous materials? Need clarification on an entry in the Hazardous Materials Regulations? PHMSA's Hazmat Information Center provides live, one-on-one assistance Monday through Friday from 9 a.m. - 5 p.m.

Call the Info Center:

  • for help with use of the Hazardous Materials Regulations (49 CFR Parts 100-185);
  • for information concerning hazardous materials transportation and rulemakings;
  • to report violations of the HMR;
  • to receive recent copies of Federal Register publications or DOT special permits;
  • to request copies of training materials;
  • to request a formal letter of interpretation*

To request a formal letter of interpretation or to mail your question, write to:

Mr. Shane Kelley
Director, Standards and Rulemaking Division
U.S. DOT/PHMSA (PHH-10)
1200 New Jersey Avenue, SE East Building, 2nd Floor
Washington, DC 20590

Last updated: Wednesday, February 7, 2018