# NTSB Safety Recommendation P-78-046 - **operation:** document - **citation:** P-78-046 - **title:** NTSB Safety Recommendation P-78-046 - **source type:** guidance - **agency:** National Transportation Safety Board - **status:** guidance - **official:** true - **published on:** 1978-08-21 - **effective on:** 1978-08-21 - **summary:** DEVISE SOME METHOD OF PHYSICALLY MARKING AND IDENTIFYING HIGH- AND LOW-PRESSURE MAINS IF THEY ARE THE SAME SIZE AND ARE INSTALLED ON THE SAME SIDE OF THE STREET OR HAVE THE POSSIBILITY OF CROSSING EACH OTHER DURING INSTALLATION. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/ntsb-recommendation-p-78-046.json - **markdown:** https://regulus.evalyn.ai/document/ntsb-recommendation-p-78-046.md - **app url:** https://regulus.evalyn.ai/document/ntsb-recommendation-p-78-046 - **source url:** https://data.ntsb.gov/carol-main-public/sr-details/P-78-046 **body:** NTSB safety recommendation P-78-046. DEVISE SOME METHOD OF PHYSICALLY MARKING AND IDENTIFYING HIGH- AND LOW-PRESSURE MAINS IF THEY ARE THE SAME SIZE AND ARE INSTALLED ON THE SAME SIDE OF THE STREET OR HAVE THE POSSIBILITY OF CROSSING EACH OTHER DURING INSTALLATION. Priority: CLASS II Overall Status: Closed - Acceptable Alternate Action Issued Date: 1978-08-21 Adopted Date: 1978-08-08 Overall Date Closed: 1988-06-08 Synopsis: ON MAY 17, 1978, A COLUMBIA GAS OF OHIO, INC., CONSTRUCTION CREW, MISTAKING AN 8-INCH, LOW-PRESSURE STEEL GAS MAIN FOR AN 8-INCH, HIGH-PRESSURE STEEL GAS MAIN, DRILLED A SMALL PILOT BIT HOLE THROUGH THE WALL OF THE LOW-PRESSURE GAS MAIN AND BEGAN TO CUT INTO THE PIPE WALL WITH A LARGE DIAMETER BIT. GAS FROM THE HIGH PRESSURE GAS SYSTEM ENTERED THE 14-INCH WATER COLUMN LOW-PRESSURE GAS MAIN AND RAPIDLY INCREASED THE PRESSURE IN THE LOW-PRESSURE SYSTEM IN A 4.8-SQUARE-MILE AREA OF MANSFIELD. THE MANSFIELD FIRE DEPARTMENT BEGAN RECEIVING REPORTS OF FIRES CAUSED BY EXCESSIVELY HIGH APPLIANCE FLAMES ON GAS APPLIANCES. THERE WERE NO FATALITIES OR INJURIES REQUIRING HOSPITALIZATION. PROPERTY DAMAGE TO 16 HOUSES RESULTED FROM THE IGNITION OF NEARBY COMBUSTIBLES BY HIGH PILOT FLAMES; 5 OF THESE HOUSES WERE EXTENSIVELY DAMAGED. Ntsbnumber: DCA78FP019 Report Number: None Addressee Name: NiSource, Inc. (formerly Columbia Gas) Addressee Status: Closed - Acceptable Alternate Action Addressee Date Closed: 1988-06-08 Addressee Organization Type: P-Private Industry Communication Date: 1978-09-25 Communication Type: Official Correspondence Communication Contents: COLUMBIA GAS OF OHIO LTR: THIS RECOMMENDATION MUST BE CONSIDERED FURTHER BY COLUMBIA GAS. THERE IS NO PRACTICAL WAY TO ACCOMPLISH THIS AT PRESENT. A CREW COULD STILL NOT BE ASSURED THAT THE MARKING WAS RELIABLE. COLUMBIA BELIEVES RECOMMENDATION P-78-45 IS THE POSITIVE WAY TO IDENTIFY THIS TYPE OF SITUATION. Addressee Organization Type: P-Private Industry Communication Date: 1988-04-18 Communication Type: Official Correspondence Communication Contents: COLUMBIA HAS NOT BEEN ABLE TO DEVISE ANY PRACTICAL "METHOD OF PHYSICALLY MARKING AND IDENTIFYING" MAINS OF SIMILAR SIZE LOCATED IN CLOSE PROXIMITY TO EACH OTHER THAT WOULD BE PERMANENT AND WOULD INSURE POSITIVE IDENTIFICATION. EVEN IF A PRACTICAL METHOD OF MAIN IDENTIFICATION OF NEW CONSTRUCTION WAS AVAILABLE, IT WOULD NOT ADDRESS THE APPROXIMATELY 15,000 MILES OF EXISTING MAINS. ALSO, IT WOULD NOT ADDRESS FUTURE PRESSURE UPRATES AND DOWNRATES OF MAINS. HOWEVER, COLUMBIA HAS INCLUDED THE FOLLOWING WORDING IN ITS TIE-IN POLICY AND PROCEDURE TO INSURE A MORE POSITIVE MEANS OF PRESSURE IDENTIFICATION: OVERPRESSURE PREVENTION TO AVOID THE ACCIDENTAL INTRODUCTION OF GAS INTO THE WRONG PIPING SYSTEM, LINE PRESSURE AND CONTENT SHALL BE VERIFIED AT EACH TIE-IN LOCATION PRIOR TO COMMENCING THE TIE-IN. LINE PRESSURE SHALL BE VERIFIED USING A PRESSURE GAUGE, OR OTHER POSITIVE MEANS. NOTE: IT SHOULD BE RECOGNIZED THAT THE INFORMATION ON OPERATING MAPS MAY BE INACCURATE OR INCOMPLETE. AS SUCH, THEY ARE CONSIDERED UNRELIABLE FOR THE PURPOSE OF IDENTIFYING MAINS WHICH ARE INVOLVED IN THE TIE IN. DISCUSSION WITH OTHER UTILITIES HAS SUPPORTED COLUMBIA'S ORIGINAL RESPONSE TO THE SAFETY BOARD. THUS, COLUMBIA CONTINUES TO STRESS THROUGH ITS TRAINING, THE NEED TO DETERMINE MAIN PRESSURE BY POSITIVE MEANS PRIOR TO COMMENCING ANY PHYSICAL TIE-IN. PERFORMANCE IN COMPLYING WITH THIS PROCEDURE HAS BEEN CLOSELY MONITORED BY MANAGEMENT THROUGH AUDITS AND CREW EVALUATIONS. Addressee Organization Type: P-Private Industry Communication Date: 1988-06-17 Communication Type: Official Correspondence Communication Contents: RECOMMENDATIONS P-78-46 AND P-78-47 SHOULD BE LOOKED AT AS RELATED TO EACH OTHER AND NOT AS SEPARATE ENTITIES. BOTH RECOMMENDATIONS ARE DESIGNED TO PREVENT THE INADVERTENT TAPPING OF AN INCORRECT PIPELINE, ESPECIALLY IF IT IS IN PROXIMITY TO ANOTHER PIPELINE OPERATING AT A DIFFERENT PRESSURE. RECOMMENDATION P-78-46 RECOMMENDS A MEANS OF POSITIVE IDENTIFICATION OF THE PIPELINE. COLUMBIA HAS COMPLIED WITH THIS RECOMMENDATION BY REQUIRING A PRESSURE CHECK BEFORE COMMENCING ANY TIE-IN ACTIVITY. RECOMMENDATION P-78-47 RECOMMENDS THAT MAPPING PROCEDURES REQUIRE GREATER DETAIL IN CONGESTED AREAS SUCH AS AT INTERSECTIONS. AS STATED IN OUR LETTER OF APRIL 18, 1988, WE BELIEVE THAT EVEN BEFORE THE MANSFIELD INCIDENT OUR MAPS WERE ADEQUATE IN THAT CONGESTED AREAS WERE DETAILED AT A LARGER SCALE EITHER IN THE MARGINS OF THE MAP OR ON SUPPLEMENTAL SHEETS. REGARD LESS OF THE SCALE OF THE DETAIL, ITS VALUE IS ONLY AS GOOD AS ITS ACCURACY. AS IS THE CASE IN THE MAPPING OF FACILI TIES BY ALL UTILITIES, COLUMBIA ACKNOWLEDGES THAT AT ANY GIVEN TIME ITS MAPS CANNOT BE 100% ACCURATE. WITH THIS IN MIND, COLUMBIA HAS, SINCE THE MANSFIELD INCIDENT, EMPHA SIZED, THROUGH SPECIFIC TRAINING, THAT THE MAPS ARE TO BE USED AS A GENERAL GUIDELINE, REGARDLESS OF DETAIL, AND THAT POSITIVE LOCATION AND IDENTIFICATION IS REQUIRED BEFORE MAKING A TIE-IN. WE APPRECIATE THE OPPORTUNITY TO CLARIFY OUR POSITION REGARDING THIS MATTER AND REQUEST THAT BASED ON THE ABOVE THE BOARD WILL RECONSIDER THEIR ACTION REGARDING P-78-47 AND REVISE ITS STATUS TO AN ACCEPTABLE CLASSIFICA TION. Addressee Organization Type: P-Private Industry Communication Date: 1988-02-23 Communication Type: Official Correspondence Addressee Organization Type: P-Private Industry Communication Date: 1978-12-14 Communication Type: Official Correspondence Addressee Organization Type: P-Private Industry Communication Date: 1988-02-23 Communication Type: Official Correspondence Addressee Organization Type: P-Private Industry Communication Date: 1988-06-07 Communication Type: Official Correspondence Addressee Organization Type: P-Private Industry Communication Date: 1988-09-27 Communication Type: Official Correspondence - **truncated:** false - **body characters:** 5883