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Safety Recommendation Details

Safety Recommendation P-18-002
Synopsis: The National Transportation Safety Board (NTSB) is providing the following information to urge the Pipeline and Hazardous Materials Safety Administration (PHMSA) and Honeywell to take action on safety recommendations intended to prevent the incorrect installation of PermaLock mechanical tapping tee assemblies in gas distribution systems. These recommendations are derived from our ongoing investigation of a fatal accident involving a natural gas explosion and fire in Millersville, Pennsylvania. The NTSB is issuing two recommendations to PHMSA and two recommendations to Honeywell.
Recommendation: TO THE PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION: Reference the use of external sources of information for threat identification in your frequently asked questions for preparation of distribution integrity management programs.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Pipeline
Location: Millersville, PA, United States
Is Reiterated: No
Is Hazmat: No
Accident #: DCA17FP006
Accident Reports: Gas Explosion Destroyed HomesSafety Recommendation Report: Installation of PermaLock Mechanical Tapping Tee Assemblies​Pipeline Accident Brief: UGI Utilities Natural Gas-Fueled Explosion Millersville, Pennsylvania July 2, 2017
Report #: PSR-18-01
Accident Date: 7/2/2017
Issue Date: 6/25/2018
Date Closed: 2/4/2019
Addressee(s) and Addressee Status: PHMSA (Closed - Acceptable Action)
Keyword(s): Hazmat

Safety Recommendation History
From: NTSB
Date: 2/4/2019
Response: We issued this recommendation out of concern that gas distribution companies other than the operator in the Millersville accident might not be aware of the problems with installing PermaLock tees when preparing their DIMPs. We note that you posted a reference to our safety recommendation report about the Millersville accident on your DIMP resources webpage, under “Advisory Bulletins,” to direct operators to this external source of information. We agree with you that posting this reference—and your current FAQ C.4.a.5, “What comprises ‘reasonably available’ information?”—ensures that operators consult external sources for information during their threat identification process. Therefore, Safety Recommendation P-18-2 is classified CLOSED--ACCEPTABLE ACTION.

Date: 8/31/2018
Response: -From Howard L. Elliott, Administrator: We concur and propose closure of the recommendation. PHMSA has posted a reference to the NTSB Safety Recommendation Report, Installation of PermaLock Mechanical Tapping Tee Assemblies, on the DIMP Resources webpage under Advisory Bulletins at to communicate to operators this external source of information for threat identification. PHMSA believes that a combination of posting this reference to the NTSB report and our current frequently asked questions (FAQs) meets the NTSB's intent of ensuring that operators consult external sources for information in their threat identification process. PHMSA agrees that operators are responsible for using all relevant external sources in the threat identification step of their distribution integrity management programs. PHMSA uses FAQs to support implementation of the regulations by operators and regulators . These FAQs are important for performance-based regulations like DIMP. PHMSA posts public FAQs and other important information and resources. PHMSA's current DIMP FAQ includes C.4.a.5, "What comprises 'reasonably available' information?" {...}PHMSA expects that operators will devote sufficient effort to develop as thorough an understanding of their pipelines as they can while using reasonable effort. [...} Operators need to review all records that are relevant to the current condition of the pipe or have a significant impact on the integrity of the pipe.{. ..} Operators must identify additional information that is needed to fill gaps due to missing, inaccurate, or incomplete records and develop a plan to collect it. They may collect this information through their normal activities including those that go beyond those activities specified in Part 192. For example, missing facility location, material and condition data can be gained when the pipe is located and/or exposed. Operators could involve maintenance personnel in their information collection activities, surveying them about unusual circumstances they have encountered in their activities and/or asking them to review resulting system descriptions and identify any information they believe is useful that is not already included. CONCLUSION PHMSA is committed to continued improvements in pipeline safety, and we take seriously our responsibility to address all NTSB recommendations. We think the recommended actions discussed above adequately address the Board's safety concerns to prevent similar future incidents. We look forward to working with your office in the future as we continue our efforts to ensure the safe, reliable, and environmentally sound operation of the Nation's pipeline transportation system.

From: NTSB
Date: 6/25/2018
Response: On June 18, 2018, the National Transportation Safety Board (NTSB) adopted its safety recommendation report Installation of PermaLock Mechanical Tapping Tee Assemblies, PSR-18/01. This report is based on our ongoing investigation of a fatal accident involving a natural gas explosion and fire in Millersville, Pennsylvania, on July 2, 2017. The details of the ongoing investigation and the resulting safety recommendations may be found in the attached report, which can also be accessed at Among the Safety Recommendations are two recommendations issued to the Pipeline and Hazardous Materials Safety Administration, which can be found on page 9 of the report. The NTSB is vitally interested in these recommendations because they are designed to prevent accidents and save lives. We would appreciate a response within 90 days, detailing the actions you have taken or intend to take to implement these recommendations. When replying, please refer to the safety recommendations by number. We encourage you to submit your response to If it exceeds 10 megabytes, including attachments, please e-mail us at the same address for instructions. Please do not submit both an electronic copy and a hard copy of the same response.