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Safety Recommendation Details

Safety Recommendation P-77-036
Details
Synopsis: ON DECEMBER 7, 1976, A NATURAL GAS COMPRESSOR FAILED AND THEN EXPLODED AND BURNED AT AN EXXON GAS SYSTEM, INC., STATION NEAR ROBSTOWN, TEXAS. AN EMERGENCY SHUTDOWN SYSTEM WAS ACTIVATED, BUT FOUR AUTOMATED FIRE GATE VALVES DID NOT CLOSE. ANOTHER EMERGENCY CONTROL SYSTEM ALSO FAILED TO AUTOMATICALLY CLOSE THE SHUTOFF VALVES LEADING TO TWO OF THE FIVE COMPRESSORS IN THE STATION. A SECOND EXPLOSION OCCURRED WITHIN THE BURNING BUILDING. THE FIRE KILLED ONE PERSON, INJURED TWO PERSONS, AND DESTROYED THREE ENGINE-DRIVEN COMPRESSORS AND THE COMPRESSOR BUILDING.
Recommendation: ADD TO 49 CFR 192.729 A SECTION TO REQUIRE THE PROPER TORQUING PROCEDURES FOR STUDS, AS SPECIFIED BY THE COMPRESSOR MANUFACTURER, WHEN REASSEMBLING COMPRESSORS AFTER MAINTENANCE WORK. INCLUDE PERIODIC TESTING OF THESE STUDS, BY ULTRASONIC OR OTHER MEANS, TO INSURE THEIR INTEGRITY DURING OPERATION.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Unacceptable Action
Mode: Pipeline
Location: Robstown, TX, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA77MP005
Accident Reports:
Exxon Gas System, Inc., Natural Gas Explosion and Fire
Report #: PAR-77-03
Accident Date: 12/7/1976
Issue Date: 10/31/1977
Date Closed: 9/3/1985
Addressee(s) and Addressee Status: RSPA (Closed - Unacceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: RSPA
Date: 9/3/1985
Response:

From: RSPA
To: NTSB
Date: 3/21/1983
Response: RSPA LETTER: INCIDENTS INVOLVING COMPRESSOR STATIONS ARE A COMPARATIVELY MINOR FRACTION OF ALL INCIDENTS REPORTED TO THE MTB. SINCE 1970, THE NUMBER OF INCIDENTS INVOLVING COMPRESSOR STATIONS HAS DECLINED BOTH IN ABSOLUTE AND IN RELATIVE TERMS. SINCE 1976, THREE NTSB SAFETY RECOMMENDATIONS WERE MADE. THERE HAS BEEN SIGNIFICANT IMPROVEMENTS IN THE AVERAGE INCIDENT RATES ASSOCIATED WITH COMPRESSOR STATIONS, GENERALLY. DURING THE PERIOD 1970-1976, THE AVERAGE ANNUAL NUMBER OF INCIDENTS FOR COMPRESSOR STATIONS WAS 23.6; DURING THE PERIOD FROM 1977 TO THE PRESENT, THIS NUMBER HAS DROPPED TO 15.2.

From: NTSB
To: RSPA
Date: 1/22/1979
Response:

From: RSPA
To: NTSB
Date: 11/17/1978
Response: LETTER FROM MTB: MTB AGREES WITH THE FIRST PART OF THE RECOMMENDATION AND WILL CONSIDER INCORPORATING PROPER TORQUING PROCEDURES FOR STUDS IN THE 1979 RULEMAKING SCHEDULE. THE SECOND PART TO REQUIRE PERIODIC TESTING WILL REQUIRE FURTHER INFORMATION BEFORE ACTING. THIS WILL BE PART OF THE STUDY UNDERTAKEN AS A RESULT OF P-77-34. IF A PROBLEM IS IDENTIFIED, RULEMAKING ACTION WILL BE UNDERTAKEN.