NTSB Safety Recommendation P-06-003

NTSB safety recommendation P-06-003.

The National Transportation Safety Board recommends that the National Fuel Gas Distribution Corporation: Revise your initial qualification and requalification procedures for plastic gas pipe to ensure fusers produce test joints made from coiled pipe with characteristics similar to those experienced in the field.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 2006-06-08

Adopted Date: 2006-05-31

Overall Date Closed: 2006-12-14

Synopsis: On August 21, 2004, about 8:54 a.m., a natural gas explosion destroyed a residence located at 48 Woodland Lane in DuBois, Pennsylvania. Two residents were killed in this accident. The Safety Board determined that the probable cause of the leak, explosion, and fire in DuBois, Pennsylvania, on August 21, 2004, was the fracture of a defective butt-fusion joint and the failure of National Fuel to have an adequate program to inspect butt-fusion joints and replace those joints not meeting its inspection criteria.

Probable Cause: The National Transportation Safety Board determines that the probable cause of the leak, explosion, and fire in DuBois, Pennsylvania, on August 21, 2004, was the fracture of a defective butt-fusion joint and the failure of the National Fuel Gas Distribution Corporation to have an adequate program to inspect butt-fusion joints and replace those joints not meeting its inspection criteria.

Ntsbnumber: DCA04MP006

Report Number: PAB-06-01

Addressee Name: National Fuel Gas Distribution Corporation

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 2006-12-14

Addressee Organization Type: P-Private Industry

Communication Date: 2006-08-10

Communication Type: Official Correspondence

Communication Contents: Letter Mail Controlled 8/21/2006 2:42:19 PM MC# 2060406: As a preliminary note, NFGDC disagrees with the Safety Board’s determination contained in the Safety Recommendation that the probable case of the leak, explosion and fire . . . was the fracture of a defective butt-fusion joint and the failure of National Fuel to have an adequate program to inspect butt-fusion joints and replace those joints not meeting its inspection criteria. To the contrary, NFGDC maintains that the probable cause of the leak was a third party excavation that undermined and placed an undue bending stress on a butt-fusion joint causing a failure in the pipe adjacent to that butt-fusion joint. Further, NFGDC’s pipeline inspection program has met, and continues to meet, all applicable requirements. That disagreement notwithstanding, NFGDC has duly considered the Safety Recommendation and, consistent therewith, is implementing the changes discussed below to its procedures. Copies of the amended pages from our Operations and Maintenance Manual are enclosed as Attachments A & B. NFGDC considers these documents to contain proprietary information and request that they be treated as confidential pursuant to 49 CFR 831.6. As stated in response to P-06-2, NFGDC is revising its procedures such that that the use of butt fusions to join two sections of coiled pipe is no longer permitted. The relevant procedure now reads: Butt fusions shall not be used to join coiled pipe to coiled pipe. When joining two coils of pipe together, either: a) butt fuse a short length of straight pipe between the two coils or b) use an electrofusion coupling. See Attachment B. NFGDC has revised its qualification and re-qualification procedures accordingly. Specifically, individuals are now required to successfully complete, among other things, a stick-to-coil butt fusion in order to be qualified as detailed on NFGDC’s Plastic Pipe Joining: Hands-on Evaluation Check List which is included herewith as Attachment C. If you should have any questions, comments or concerns regarding any aspect of the foregoing, please do not hesitate to contact me at (716) 857-7575. Sincerely, James D. Ramsdell, Senior Vice President

Addressee Organization Type: P-Private Industry

Communication Date: 2006-12-14

Communication Type: Official Correspondence

Communication Contents: The Safety Board is pleased that the NFGDC has revised its procedures as follows: Butt fusions shall not be used to join coiled pipe to coiled pipe. When joining two coils of pipe together, either: a) butt fuse a short length of straight pipe between the two coils or b) use an electrofusion coupling. In addition, the NFGDC has revised its qualification and requalification procedures so that individuals are required to successfully complete, among other things, a stick-to-coil butt fusion in order to qualify as detailed according to the NFGDC’s Plastic Pipe Joining: Hands-on Evaluation Check List. Because the NFGDC has revised these procedures as recommended, Safety Recommendation P-06-3 is classified Closed Acceptable Action.