USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Safety Advisory: Unauthorized Marking and Modification of Compressed Gas Cylinders

Safety advisory notice.

This is to notify the public that RSPA is investigating the unauthorized marking and modification of high-pressure compressed gas cylinders. On March 27, 1997, RSPA inspectors entered the premises of Browns Welding Supply. They observed numerous compressed gas cylinders and found a significant number marked with an expired Retester Identification Number (RIN) or unauthorized RIN. Based on those RIN markings and the inspectors' observations, RSPA believes that many of these cylinders may not have been retested in accordance with the Hazardous Materials Regulations (49 CFR Parts 171-180)(HMR). Furthermore, the inspectors observed many cylinders that exhibited evidence of improper grinding. Unauthorized grinding can have a significant effect on a cylinder's minimum wall thickness, and therefore, its structural integrity. Unauthorized grinding can remove required markings and can be used to mask a cylinder's overall condition. Serious personal injury, death, and property damage could result from the rupture of a cylinder. Cylinders which have not been retested in accordance with the HMR may not be charged or filled with a hazardous material.

View PDF