PHMSA Warns of Heat Risks in Aging Plastic Gas Distribution Pipelines

PHMSA has issued a safety advisory warning natural gas distribution operators about heat-related failure risks in aging Aldyl A plastic pipelines, following a fatal 2023 explosion in Pennsylvania.

(P&GJ) — The Pipeline and Hazardous Materials Safety Administration (PHMSA) has issued a safety advisory urging natural gas distribution operators to address heat-related risks associated with older plastic piping, particularly systems containing Aldyl A polyethylene.

The advisory follows a 2023 explosion at a chocolate factory in West Reading, Pennsylvania, that killed seven people and injured 10 others. Investigators determined that natural gas leaked from a degraded Aldyl A pipeline, with the incident worsened by a damaged steam pipe and elevated ground temperatures.

According to findings by the National Transportation Safety Board (NTSB), Aldyl A pipe materials are more susceptible to accelerated degradation and failure when exposed to higher temperatures. The NTSB recommended that operators replace or remediate any remaining Aldyl A components still in service.

PHMSA’s advisory highlights Distribution Integrity Management Program (DIMP) requirements and calls on operators to take additional steps, including completing a one-time inventory of plastic pipeline assets located in areas with elevated temperatures. Operators are also advised to conduct ongoing monitoring during construction and maintenance activities to identify potential heat-related threats.

PHMSA emphasized that advisory bulletins serve as guidance and do not impose new regulatory requirements. The safety advisory has been published in the Federal Register.