# NTSB Safety Recommendation P-77-043 **Citation:** P-77-043 **Type / status:** guidance / guidance **Agency:** National Transportation Safety Board **Effective:** 1977-11-28 **Published:** 1977-11-28 EVALUATE THE EFFECTS UPON THE GAS SYSTEM PRIOR TO PLACING ANY PORTION OUT OF SERVICE AND TAKE ACTIONS NECESSARY TO ASSURE CONTINUED SAFE OPERATION. APPENDIX G - 12 OF THE ASME GUIDE FOR GAS TRANSMISSION AND DISTRIBUTION PIPING SYSTEMS - 1976, PROVIDES GUIDANCE TO AID IN ACCOMPLISHING THESE ACTIONS. ## Document text NTSB safety recommendation P-77-043. EVALUATE THE EFFECTS UPON THE GAS SYSTEM PRIOR TO PLACING ANY PORTION OUT OF SERVICE AND TAKE ACTIONS NECESSARY TO ASSURE CONTINUED SAFE OPERATION. APPENDIX G - 12 OF THE ASME GUIDE FOR GAS TRANSMISSION AND DISTRIBUTION PIPING SYSTEMS - 1976, PROVIDES GUIDANCE TO AID IN ACCOMPLISHING THESE ACTIONS. Priority: CLASS II Overall Status: Closed - Acceptable Action Issued Date: 1977-11-28 Adopted Date: 1977-11-23 Overall Date Closed: 1983-01-27 Synopsis: ON AUGUST 9, 1977, NATURAL GAS UNDER HIGH PRESSURE WAS BRIEFLY ALLOWED TO ENTER A LOW-PRESSURE NATURAL GAS DISTRIBUTION LINE AND OVERPRESSURED MORE THAN 750 CUSTOMER SERVICE LINES IN A SEVEN-BLOCK AREA IN EL PASO, TEXAS. FLAMES FROM GAS PILOTS AND THE BURNERS OF APPLIANCES BURNED OUT OF CONTROL AND CAUSED FIRES IN NEARBY FLAMMABLE MATERIALS. THERE WERE A FEW MINOR INJURIES AND SOME MINOR PROPERTY DAMAGE, BUT NO FATALITIES. Ntsbnumber: FTW77FP001 Report Number: None Addressee Name: Southern Union Gas Company Addressee Status: Closed--No Longer Applicable Addressee Date Closed: 1983-01-27 Addressee Organization Type: P-Private Industry Communication Date: 1982-10-29 Communication Type: Official Correspondence Communication Contents: SOUTHERN UNION GAS COMPANY LTR: THE SAFETY OF OUR CUSTOMERS THROUGH THE INTEGRITY OF OUR DISTRIBUTION SYSTEM IS OF THE UPMOST IMPORTANCE TO OUR COMPANY. TO ENSURE THAT EVERY REASONABLE SAFETY PRECAUTION IS EXERCISED WHILE DOING CONSTRUCTION OR MAINTENANCE WORK, THE FOLLOWING POLICIES SHALL BE OBSERVED: (1) PRESSURE GAUGES WILL BE INSTALLED ON BOTH THE UPSTREAM AND DOWNSTREAM SIDES OF ANY SECTION OF PIPE OR EQUIPMENT THAT IS TO BE TAKEN OUT OF SEVICE OR ALTERED. THE GAUGES SHALL BE LOCATED AT A POINT WHERE IT WILL BE EVIDENT THAT THE PRESSURES ARE REPRESENTATIVE. IF POSSIBLE, THE GAUGES SHOULD BE SO LOCATED THAT THEY CAN BE EASILY OBSERVED BY THE PERSON THAT IS PERFORMING THE WORK. (2) A PROCEDURE SHALL BE WRITTEN AND FOLLOWED FOR ANY "MAJOR" PROJECT OR ANY PROJECT THAT IS LOCATED IN CLOSE PROXIMITY TO A REGULATOR STATION. THE PROCEDURE SHALL BE APPROVED BY THE APPLICABLE C & M SUPERINTENDENT AND DISTRICT ENGINEER. (3) MEASUREMENT SHALL BE RESPONSIBLE FOR MAINTAINING PRESSURE CONTROL OF ALL METERING AND REGULATING EQUIPMENT. (4) MEASUREMENT SHALL BE NOTIFIED OF ANY WORK IN PROGRESS THAT IS IN CLOSE PROXIMITY TO A REGULATING STATION. THEY SHALL ALSO BE NOTIFIED OF ANY "MAJOR" PROJECT THAT COULD AFFECT THE DISTRIBUTION SYSTEM SHOULD AN INCIDENT OCCUR. (5) MEASUREMENT SHALL HAVE A REPRESENTATIVE PRESENT WHERE THE WORK IN PROGRESS IS WITHIN THE CLOSE PROXIMITY OF A REGULATING STATION. MEASUREMENT SHALL ALSO HAVE A REPRESENTATIVE PRESENT DURING ANY "MAJOR" ALTERATION OF A DISTRIBUTION SYSTEM. (6) NO OVERPRESSURE PROTECTION DEVICE SHALL BE TAKEN OUT OF SERVICE UNLESS THE SYSTEM IS CONTINUOUSLY MONITORED BY MEASUREMENT PERSONNEL. MEASURE MENT PERSONNEL SHALL BE PREPARED TO TAKE IMMEDIATE CORRECTIVE ACTION SHOULD A MALFUNCTION OCCUR. FAILURE TO OBSERVE THESE POLICIES BY THOSE RESPONSIBLE WILL BE GROUNDS FOR IMMEDIATE SUSPENSION FOR THE FIRST OFFENSE IF NO INCIDENT OCCURS. IF AN INCIDENT SHOULD OCCUR OR IF THE POLICIES ARE NOT OBSERVED AFTER THE FIRST WARNING, IT WILL BE CONSIDERED GROUNDS FOR IMMEDIATE TERMINATION. THIS PROCEDURE IS IN LINE WITH THE RECOMMENDATION MADE BY THE NTSB. DAVID MISTROT, WITH THE TEXAS RAILROAD COMMISSION, FOLLOWED UP ON THIS INCIDENT AT A LATER DATE. NO WRITTEN REPORT WAS MADE. Addressee Organization Type: P-Private Industry Communication Date: 1983-01-27 Communication Type: Official Correspondence Addressee Organization Type: P-Private Industry Communication Date: 1982-10-08 Communication Type: Official Correspondence ## Provenance - Official: Yes - Source: - Source ID: `ntsb-pipeline` - SHA-256: `4ec527b0e7e6405197224876a51b5a8e83e25b06e00852476d6362aba13e2485` - Retrieved: 2026-08-20T04:57:24.741Z - Exported: 2026-08-22T22:34:52.173Z - Document slug: `ntsb-recommendation-p-77-043` ### Source metadata ```json { "recordKind": "ntsb_safety_recommendation", "safetyRecommendationNumber": "P-77-043", "recommendationMode": "Pipeline", "topicMode": "Pipeline", "ntsbNumber": "FTW77FP001", "priority": "CLASS II", "overallStatus": "Closed - Acceptable Action", "overallStatusAcronym": "CAA", "overallDateClosed": "1983-01-27", "lastModifiedDate": "2016-11-15", "reportNumber": "None", "reportUrl": null, "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P77_43.pdf", "addressees": [ { "addresseeName": "Southern Union Gas Company", "addresseeStatusAcronym": "CNLA", "addresseeStatus": "Closed--No Longer Applicable", "addresseeDateClosed": "1983-01-27", "addresseeDetails": [ { "addresseeAcronym": null, "addresseeOrganizationType": "P-Private Industry", "isFromNtsb": false, "communicationDate": "1982-10-29", "communicationType": "Official Correspondence", "communicationContents": "SOUTHERN UNION GAS COMPANY LTR: THE SAFETY OF OUR CUSTOMERS THROUGH THE INTEGRITY OF OUR DISTRIBUTION SYSTEM IS OF THE UPMOST IMPORTANCE TO OUR COMPANY. TO ENSURE THAT EVERY REASONABLE SAFETY PRECAUTION IS EXERCISED WHILE DOING CONSTRUCTION OR MAINTENANCE WORK, THE FOLLOWING POLICIES SHALL BE OBSERVED: (1) PRESSURE GAUGES WILL BE INSTALLED ON BOTH THE UPSTREAM AND DOWNSTREAM SIDES OF ANY SECTION OF PIPE OR EQUIPMENT THAT IS TO BE TAKEN OUT OF SEVICE OR ALTERED. THE GAUGES SHALL BE LOCATED AT A POINT WHERE IT WILL BE EVIDENT THAT THE PRESSURES ARE REPRESENTATIVE. IF POSSIBLE, THE GAUGES SHOULD BE SO LOCATED THAT THEY CAN BE EASILY OBSERVED BY THE PERSON THAT IS PERFORMING THE WORK. (2) A PROCEDURE SHALL BE WRITTEN AND FOLLOWED FOR ANY \"MAJOR\" PROJECT OR ANY PROJECT THAT IS LOCATED IN CLOSE PROXIMITY TO A REGULATOR STATION. THE PROCEDURE SHALL BE APPROVED BY THE APPLICABLE C & M SUPERINTENDENT AND DISTRICT ENGINEER. (3) MEASUREMENT SHALL BE RESPONSIBLE FOR MAINTAINING PRESSURE CONTROL OF ALL METERING AND REGULATING EQUIPMENT. (4) MEASUREMENT SHALL BE NOTIFIED OF ANY WORK IN PROGRESS THAT IS IN CLOSE PROXIMITY TO A REGULATING STATION. THEY SHALL ALSO BE NOTIFIED OF ANY \"MAJOR\" PROJECT THAT COULD AFFECT THE DISTRIBUTION SYSTEM SHOULD AN INCIDENT OCCUR. (5) MEASUREMENT SHALL HAVE A REPRESENTATIVE PRESENT WHERE THE WORK IN PROGRESS IS WITHIN THE CLOSE PROXIMITY OF A REGULATING STATION. MEASUREMENT SHALL ALSO HAVE A REPRESENTATIVE PRESENT DURING ANY \"MAJOR\" ALTERATION OF A DISTRIBUTION SYSTEM. (6) NO OVERPRESSURE PROTECTION DEVICE SHALL BE TAKEN OUT OF SERVICE UNLESS THE SYSTEM IS CONTINUOUSLY MONITORED BY MEASUREMENT PERSONNEL. MEASURE MENT PERSONNEL SHALL BE PREPARED TO TAKE IMMEDIATE CORRECTIVE ACTION SHOULD A MALFUNCTION OCCUR. FAILURE TO OBSERVE THESE POLICIES BY THOSE RESPONSIBLE WILL BE GROUNDS FOR IMMEDIATE SUSPENSION FOR THE FIRST OFFENSE IF NO INCIDENT OCCURS. IF AN INCIDENT SHOULD OCCUR OR IF THE POLICIES ARE NOT OBSERVED AFTER THE FIRST WARNING, IT WILL BE CONSIDERED GROUNDS FOR IMMEDIATE TERMINATION. THIS PROCEDURE IS IN LINE WITH THE RECOMMENDATION MADE BY THE NTSB. DAVID MISTROT, WITH THE TEXAS RAILROAD COMMISSION, FOLLOWED UP ON THIS INCIDENT AT A LATER DATE. NO WRITTEN REPORT WAS MADE." }, { "addresseeAcronym": null, "addresseeOrganizationType": "P-Private Industry", "isFromNtsb": true, "communicationDate": "1983-01-27", "communicationType": "Official Correspondence", "communicationContents": "" }, { "addresseeAcronym": null, "addresseeOrganizationType": "P-Private Industry", "isFromNtsb": true, "communicationDate": "1982-10-08", "communicationType": "Official Correspondence", "communicationContents": "" } ] } ], "jurisdiction": "US" } ```