NTSB Safety Recommendation P-76-018

NTSB safety recommendation P-76-018.

DEVELOP COMPREHENSIVE CONSTRUCTION STANDARDS FOR THE INSTALLATION OF COMPRESSION COUPLINGS FOR EACH TYPE OF PIPE FOR WHICH EACH TYPE OF FITTING WILL BE USED. (URGENT)

Priority: CLASS I

Overall Status: Closed--No Longer Applicable

Issued Date: 1976-02-08

Adopted Date: 1976-04-29

Overall Date Closed: 1983-01-27

Synopsis: ON FEBRUARY 8, 1976, A HOUSE IN PHOENIX, ARIZONA, EXPLODED AND BURNED. OF TWO PERSONS WHO WERE HOSPITALIZED AS A RESULT OF THE ACCIDENT, ONE DIED.

Probable Cause: The National Transportation Safety Board's investigation of this accident disclosed that the natural gas at 39-psig pressure had leaked from the compression coupled connection of a 2-inch pipe appeared to have been inserted insufficiently through the gasket and into the coupling. Gas which leaked from this joint was trapped from above by heavily compacted soil; it consequently seeped into the house, where it was ignited by an unknown source. The 2-inch plastic pipe, which was installed in 1968 by the Arizona Public Service Company, was damaged by an excavator in 1969. The gas company repaired the leak by installing a 6-inch-ling compression coupling to connect each end of the severed 2-inch plastic pipe. The repaired section was wrapped with tape which extended 3 to 4 inches over the pipe on each side of the coupling.

Ntsbnumber: DCA76FP015

Report Number: None

Addressee Name: Arizona Public Service Company

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1983-01-27

Addressee Acronym: APS

Addressee Organization Type: P-Private Industry

Communication Date: 1982-11-12

Communication Type: Official Correspondence

Communication Contents: ARIZONA PUBLIC SERVICE COMPANY LTR: BASED UPON A REVIEW OF EXISTING CONSTRUCTION STANDARDS AND COUPLED WITH APS' DECISION TO DISCONTINUE FUTURE USE OF THE SUBJECT COUPLINGS, THERE DOES NOT APPEAR TO BE A NEED FOR A COMPREHENSIVE SET OF NEW INSTALLATION CONSTRUCTION STANDARDS.

Addressee Acronym: APS

Addressee Organization Type: P-Private Industry

Communication Date: 1982-10-05

Communication Type: Official Correspondence

Addressee Acronym: APS

Addressee Organization Type: P-Private Industry

Communication Date: 1983-01-27

Communication Type: Official Correspondence