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Site Notification

Site Notification

The latest general information on the Coronavirus (COVID-19) is available on Coronavirus.gov. For PHMSA contact information during the COVID-19 health emergency, please visit our page.

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MR Number Brochure PDF

PHMSA no longer issues R-number Approvals and has transitioned to M-number Approvals that include expiration dates in an effort to accurately locate and verify manufacturing facilities prior to performing safety inspections.

DOT is committed to ensuring that information is available in appropriate alternative formats to meet the requirements of persons who have a disability. If you require an alternative version of files provided on this page, please contact PHMSA-Accessibility@dot.gov.
Published Date: Sunday, July 1, 2018
Issued Date: Sunday, July 1, 2018