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PHMSA Safety Advisory Notice: Special Permits for Composite Gas Cylinders

Tuesday, January 12, 2021

On March 3, 2020, the Pipeline and Hazardous Materials Safety Administration (PHMSA) conducted an Investigative Hearing in response to incidents and roll-over crashes associated with operations using packagings authorized under certain Hazardous Materials Special Permits for the manufacture, mark, sale and use of non-DOT specification fully wrapped fiber reinforced composite gas cylinders.  The gas cylinders are used for the transportation of compressed natural gas (CNG) and other hazardous materials.  

As a result of the information presented at the hearing and subsequent evaluation, PHMSA is publishing this Safety Advisory Notice with recommendations to help facilitate the safe transportation of CNG under the terms of each related special permit.  See the Safety Advisory Notice in the related documents section for more details.