PHMSA Issues Safety Advisory: Plastic Gas Pipelines

PHMSA Issues Safety Advisory on Heat Risks in Older Plastic Gas Pipelines

On January 23, 2025, the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) issued a Safety Advisory to natural gas distribution pipeline operators that highlights risks associated with older plastic pipeline materials when exposed to elevated temperatures. The advisory responds to findings from a fatal 2023 natural gas pipeline explosion in Pennsylvania that claimed multiple lives and caused significant community impact.

Federal Register Publication and Advisory Scope

The advisory has been published in the Federal Register, and provides guidance to operators on assessing and mitigating heat-related degradation risks, particularly for plastic piping components, such as those made from Aldyl A polyethylene.

Background of the West Reading Explosion:

On March 24, 2023, a natural gas-fueled explosion and fire occurred at the R.M. Palmer Company chocolate factory in West Reading, Pennsylvania. The incident resulted in the deaths of seven people, injuries to ten others, and destroyed part of the facility. The National Transportation Safety Board (NTSB) investigation determined that the explosion was caused by a leak from a retired Aldyl A polyethylene service tee that had degraded over time, allowing natural gas to accumulate and subsequently ignite. The degradation was accelerated by elevated ground temperatures caused by a nearby steam pipe leak.

NTSB Investigation and Findings

Additional details on the incident and the National Transportation Safety Board’s findings are available through the agency’s public investigation docket for the UGI Corporation natural gas–fueled explosion and fire in West Reading, Pennsylvania.

PHMSA Response and DIMP Obligations

In response to the NTSB’s recommendations, PHMSA issued a safety advisory bulletin reminding pipeline operators of their existing Distribution Integrity Management Program (DIMP) obligations under 49 CFR Part 192, Subpart P, and encouraging proactive risk management of plastic pipeline assets in elevated temperature environments.

Key Safety Advisory Takeaways

Key points from the advisory include:

Reinforcement of DIMP Requirements: Operators should ensure their integrity management programs account for specific threats posed by plastic materials, including heat-induced degradation.
Inventory of Plastic Assets: A one-time inventory of plastic piping and components in heat-affected areas is recommended.
Continuous Monitoring: Operators should monitor plastic assets for degradation during construction, maintenance, and operations.
Replacement or Remediation: Where appropriate, operators should evaluate the replacement or remediation of plastic components, particularly those known to be susceptible to degradation.

Why This Advisory Matters

PHMSA notes that advisory bulletins are guidance documents and do not impose new regulatory obligations but rather clarify and reinforce existing safety practices.

Preventing Future Tragedies

While advisory bulletins do not change regulatory requirements, they provide important safety guidance to help pipeline operators identify and mitigate risks that may not be fully addressed by current practices. The West Reading tragedy underscores how material degradation in legacy pipeline systems, particularly older plastic pipes and components, can have severe consequences when combined with environmental stressors like heat.

Proactive asset identification, monitoring, and targeted remediation can help prevent similar incidents and protect workers, the public, and critical infrastructure.

ICC Compliance Center has a team of full-time Regulatory Experts who have years of experience and are certified/recognized in their field of expertise. Ask us your tough questions by calling 888.442.9628 (USA) or 888.977.4834 (Canada) or send us an email.