{"operation":"document","citation":"DCA14MP002","title":"Natural Gas-Fueled Building Explosion and Resulting Fire","source_type":"incident","agency":"National Transportation Safety Board","status":"current","official":true,"published_on":"2020-11-13","effective_on":"2014-03-12","summary":"Pipeline occurrence. in Manhattan, NY, USA. on 2014-03-12","machine_formats":{"json":"https://regulus.evalyn.ai/document/ntsb-case-dca14mp002.json","markdown":"https://regulus.evalyn.ai/document/ntsb-case-dca14mp002.md"},"app_url":"https://regulus.evalyn.ai/document/ntsb-case-dca14mp002","source_url":"https://www.ntsb.gov/investigations/Pages/DCA14MP002.aspx","body":"NTSB investigation DCA14MP002.\n\nEvent Date: 2014-03-12\n\nEvent City: Manhattan\n\nEvent State Or Region: NY\n\nEvent Country: USA\n\nCompletion Status: Completed\n\nProbable cause: The National Transportation Safety Board determines that the probable cause of the accident was (1) the failure of the defective fusion joint at the service tee, installed by Consolidated Edison Company of New York, Inc., in 2011, that allowed natural gas to leak from the gas main and migrate into the building where it ignited and (2) a breach in the sewer line that went unrepaired by the New York City Department of Environmental Protection since at least 2006 that allowed groundwater and soil to flow into the sewer, resulting in a loss of support for the gas main, which caused the line to sag and overstressed the defective fusion joint.\n\nTier1Name: Unknown\n\nTier2Name: Pipe structural malfunction/failure\n\nTier1Name: System operating\n\nTier2Name: Pipe structural malfunction/failure\n\nTier1Name: System not operating\n\nTier2Name: Pipe structural malfunction/failure\n\nTier1Name: Initiating product flow\n\nTier2Name: Servicing event\n\nTier1Name: System operating\n\nTier2Name: Inspection event\n\nTier1Name: System shutdown\n\nTier2Name: Emergency shutoff\n\nTier1Name: Post-release\n\nTier2Name: Evacuation\n\nTier1Name: Post-release\n\nTier2Name: Emergency response\n\nTier1Name: System operating, changing flow/pressure\n\nTier2Name: Fire/explosion (post-release)\n\nTier1Name: System maintenance\n\nTier2Name: System disabled\n\nTier1Name: System operating\n\nTier2Name: Miscellaneous/other\n\nFinding Tier1Name: Organizational\n\nFinding Tier2Name: Management\n\nFinding Tier3Name: Communication (organizational)\n\nFinding Modifier Name: Pipeline operator\n\nFinding Report Text: Organizational - Management - Communication (organizational) - Pipeline operator\n\nFinding Tier1Name: Organizational\n\nFinding Tier2Name: Support/oversight/monitoring\n\nFinding Tier3Name: Oversight\n\nFinding Modifier Name: State/Local agency\n\nFinding Report Text: Organizational - Support/oversight/monitoring - Oversight - State/Local agency\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline structure\n\nFinding Tier3Name: Joint/weld/seam\n\nFinding Modifier Name: Failure\n\nFinding Report Text: Pipeline - Pipeline structure - Joint/weld/seam - Failure\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline structure\n\nFinding Tier3Name: Joint/weld/seam\n\nFinding Modifier Name: Design\n\nFinding Report Text: Pipeline - Pipeline structure - Joint/weld/seam - Design\n\nFinding Tier1Name: Personnel\n\nFinding Tier2Name: Experience/knowledge\n\nFinding Tier3Name: Skill/ability\n\nFinding Modifier Name: Pipeline maintenance personnel\n\nFinding Report Text: Personnel - Experience/knowledge - Skill/ability - Pipeline maintenance personnel\n\nFinding Tier1Name: Personnel\n\nFinding Tier2Name: Action/decision\n\nFinding Tier3Name: Information processing/decision making\n\nFinding Modifier Name: Pipeline maintenance personnel\n\nFinding Report Text: Personnel - Action/decision - Information processing/decision making - Pipeline maintenance personnel\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline handling/service\n\nFinding Tier3Name: Securing\n\nFinding Modifier Name: Unintentional use/operation\n\nFinding Report Text: Pipeline - Pipeline handling/service - Securing - Unintentional use/operation\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline operation/capability\n\nFinding Tier3Name: Pipeline integrity/capacity\n\nFinding Modifier Name: Design\n\nFinding Report Text: Pipeline - Pipeline operation/capability - Pipeline integrity/capacity - Design\n\nFinding Tier1Name: Environment/Infrastructure\n\nFinding Tier2Name: Conditions/weather/phenomena\n\nFinding Tier3Name: Precipitation\n\nFinding Modifier Name: Use of related info\n\nFinding Report Text: Environment/Infrastructure - Conditions/weather/phenomena - Precipitation - Use of related info\n\nFinding Tier1Name: Environment/Infrastructure\n\nFinding Tier2Name: Conditions/weather/phenomena\n\nFinding Tier3Name: Precipitation\n\nFinding Modifier Name: Unknown/Not determined\n\nFinding Report Text: Environment/Infrastructure - Conditions/weather/phenomena - Precipitation - Unknown/Not determined\n\nFinding Tier1Name: Environment/Infrastructure\n\nFinding Tier2Name: Task environment\n\nFinding Tier3Name: Pressures/demands\n\nFinding Modifier Name: Awareness of condition\n\nFinding Report Text: Environment/Infrastructure - Task environment - Pressures/demands - Awareness of condition\n\nFinding Tier1Name: Personnel\n\nFinding Tier2Name: Action/decision\n\nFinding Tier3Name: Action\n\nFinding Modifier Name: Other government personnel\n\nFinding Report Text: Personnel - Action/decision - Action - Other government personnel\n\nFinding Tier1Name: Environment/Infrastructure\n\nFinding Tier2Name: Conditions/weather/phenomena\n\nFinding Tier3Name: Precipitation\n\nFinding Modifier Name: Awareness of condition\n\nFinding Report Text: Environment/Infrastructure - Conditions/weather/phenomena - Precipitation - Awareness of condition\n\nFinding Tier1Name: Environment/Infrastructure\n\nFinding Tier2Name: Conditions/weather/phenomena\n\nFinding Tier3Name: Precipitation\n\nFinding Modifier Name: Contributed to outcome\n\nFinding Report Text: Environment/Infrastructure - Conditions/weather/phenomena - Precipitation - Contributed to outcome\n\nOfficial NTSB investigation data. NTSB findings determine probable cause and make safety recommendations; they do not adjudicate civil liability or regulatory violations.\n\nWhat Happened\nOn March 12, 2014, about 9:30 a.m. eastern daylight time, two adjacent multiuse five story buildings were destroyed by a natural gas fueled explosion and resulti ng fire. The buildings were situated on the west side of Park Avenue between East 116th Street and East 117th Street in the East Harlem district of the Borough of Manhattan in New York City. The violent explosion damaged buildings on the east and west side s of Park Avenue and along East 116th and East 117th Streets. The Metro North R ailroad suspended rail service for about 7 1/2 hours on the elevated railway along Park Avenue because of debris from the explosion on the track. Eight people died, more than 50 people were injured, and more than 100 families were displaced from their homes as a result of this accident. The cost to Consolidated Edison Company of New York, Inc. (Con Edison), of equipment damages, emergency response activities, remediation, and replacement exceeded $1.9 million.\n\nWhat We Found\nWe determined that the probable cause of the accident was (1) the failure of the defective fusion joint at the service tee, installed by Consolidated Edison Company of New York, Inc., in 2011, that allowed natural gas to leak from the gas main and migrate into the building where it ignited and (2) a breach in the sewer line that went unrepaired by the New York City Department of Environmental Protection since at least 2006 that allowed groundwater and soil to flow into the sewer, resulting in a loss of support for the gas main, which caused the line to sag and overstressed the defective fusion joint.\n\nWhat We Recommended\nAs a result of this investigation, We made the following new safety recommendations:\nTo the City of New York: Implement a written program or procedure to ensure the integrity of your sewer lines, repair breaches in a timely manner, and coordinate with other agencies to identify and address potential soil disruption and voids. (P-15-33)\nTo Consolidated Edison Company of New York, Inc.:\nRevise your plastic pipe fusion welding procedure to require cleaning of the surfaces to be welded with suitable solvents to remove all dirt, water, oil, paint, and other contaminants as recommended in ASTM F2620, Standard Practice for Heat Fusion Joining of Polyethylene Pipe and Fittings. (P-15-34)\nRevise your plastic pipe fusion welding procedure to specify that the solidified beads should be visually examined after completing a joint to ensure the beads are uniformly shaped and sized around the joint as recommended in ASTM F2620, Standard Practice for Heat Fusion Joining of Polyethylene Pipe and Fittings. (P-15-35)\nProvide clear written guidance to the Gas Emergency Response Center staff on the conditions for promptly notifying the New York City Fire Department and provide additional staff training. (P-15-36)\nExtend your gas main isolation valve installation program to include strategic locations where long distribution mains currently cannot be isolated, giving priority to pipelines in more densely populated areas. (P-15-37)\nTo the New York State Public Service Commission: Revise the New York State Department of Public Service gas utility operator program to ensure all elements of the regulations are included in the 5-year audit plan. (P-15-38)\n\nPAR-15-01\n<<<PAGE 1>>>\n\nNatural Gas-Fueled Building Explosion and Resulting Fire\nNew York City, New York\nMarch 12, 2014\nAccident Report\nNTSB/PAR-15/01\nPB2015-104889\nNational\nTransportation\nSafety Board\n\n<<<PAGE 2>>>\n\nNTSB/PAR-15/01\nPB2015-104889\nNotation 8696\nAdopted June 9, 2015\nPipeline Accident Report\nNatural Gas-Fueled Building Explosion and Resulting Fire\nNational\nTransportation\nSafety Board\n490 L’Enfant Plaza, S.W.\nWashington, D.C. 20594\n\n<<<PAGE 3>>>\n\nNational Transportation Safety Board. 2015. Natural Gas-Fueled Building Explosion and Resulting\nFire. Pipeline Accident Report NTSB/PAR-15/01. Washington, DC.\nAbstract:\nOn March 12, 2014, about 9:30 a.m. eastern daylight time, two adjacent multiuse five-story buildings\nwere destroyed by a natural gas-fueled explosion and resulting fire. The buildings were situated on the\nwest side of Park Avenue between East 116th Street and East 117th Street in the East Harlem district of\nthe Borough of Manhattan in New York City. The violent explosion damaged buildings on the east and\nwest sides of Park Avenue and along East 116th and East 117th Streets. Eight people died, more than 50\npeople were injured, and more than 100 families were displaced from their homes as a result of this\naccident. The accident investigation focused on the following safety issues: the adequacy of Consolidated\nEdison’s (Con Edison) quality assurance and quality control procedures for joining plastic pipes, the\neffectiveness of Con Edison’s public awareness program, the adequacy of Con Edison’s gas odor report\nresponse, the effectiveness of the New York City Department of Environmental Protection sewer integrity\nprogram, and the effectiveness of federal and state oversight. Safety recommendations are made to the\nNew York State Public Service Commission, the City of New York, and Con Edison.\nThe National Transportation Safety Board (NTSB) is an independent federal agency dedicated to promoting\naviation, railroad, highway, marine, and pipeline safety. Established in 1967, the agency is mandated by Congress\nthrough the Independent Safety Board Act of 1974 to investigate transportation accidents, determine the probable\ncauses of the accidents, issue safety recommendations, study transportation safety issues, and evaluate the safety\neffectiveness of government agencies involved in transportation. The NTSB makes public its actions and decisions\nthrough accident reports, safety studies, special investigation reports, safety recommendations, and statistical\nreviews.\nThe NTSB does not assign fault or blame for an accident or incident; rather, as specified by NTSB regulation,\n“accident/incident investigations are fact-finding proceedings with no formal issues and no adverse parties … and\nare not conducted for the purpose of determining the rights or liabilities of any person.” 49 C.F.R. § 831.4.\nAssignment of fault or legal liability is not relevant to the NTSB’s statutory mission to improve transportation safety\nby investigating accidents and incidents and issuing safety recommendations. In addition, statutory language\nprohibits the admission into evidence or use of any part of an NTSB report related to an accident in a civil action for\ndamages resulting from a matter mentioned in the report. 49 U.S.C. § 1154(b).\nFor more detailed background information on this report, visit http://www.ntsb.gov/investigations/dms.html and\nsearch for NTSB accident ID DCA14MP002. Recent publications are available in their entirety on the Internet at\nhttp://www.ntsb.gov. Other information about available publications also may be obtained from the website or by\ncontacting:\nNational Transportation Safety Board\nRecords Management Division, CIO-40\n490 L’Enfant Plaza, SW\nWashington, DC 20594\n(800) 877-6799 or (202) 314-6551\nNTSB publications may be purchased from the National Technical Information Service. To purchase this\npublication, order product number PB2015-104889 from:\nNational Technical Information Service\n5301 Shawnee Rd.\nAlexandria, VA 22312\n(800) 553-6847 or (703) 605-6000\nhttp://www.ntis.gov/\n\n<<<PAGE 4>>>\n\nNTSB Pipeline Accident Report\nContents\nFigures ........................................................................................................................................... iii\nTable ................................................................................................................................................v\nAcronyms and Abbreviations ..................................................................................................... vi\nExecutive Summary .................................................................................................................... vii\n1 Factual Information ....................................................................................................................1\n1.1 Accident Synopsis ......................................................................................................................1\n1.2 Accident Site ..............................................................................................................................2\n1.3 Gas Odor Calls to Con Edison ...................................................................................................2\n1.4 Emergency Response .................................................................................................................4\n1.5 Injuries .......................................................................................................................................5\n1.6 Damages .....................................................................................................................................5\n1.7 Natural Gas and Other Utilities..................................................................................................6\n1.8 Preaccident Activities ................................................................................................................8\n1.8.1 Gas Odor Reports ............................................................................................................8\n1.8.2 Gas Leak Surveys ..........................................................................................................10\n1.8.3 Water Leak Surveys .......................................................................................................10\n1.8.4 Sewer Inspections ..........................................................................................................10\n1.8.5 Street Cave-ins and Repairs ...........................................................................................11\n1.9 Con Edison Operations ............................................................................................................12\n1.9.1 Heat Fusion Procedure ...................................................................................................12\n1.9.2 Emergency Call Response .............................................................................................13\n1.9.3 Pipeline Integrity Management ......................................................................................14\n1.9.4 Emergency Preparedness and Response ........................................................................14\n1.10 Tests and Research .................................................................................................................15\n1.10.1 Materials Laboratory Examination of Accident Pipe and Joint ...................................15\n1.10.2 Saddle Fusion Joints ....................................................................................................17\n1.10.3 Accident Service Tee ...................................................................................................19\n1.10.4 Accident Saddle Joint Fusion Bead Size .....................................................................21\n1.10.5 Gas Pipe Size and Dimensional Conformity ...............................................................22\n1.10.6 Mechanical and Physical Properties ............................................................................22\n1.10.7 Finite Element Modeling .............................................................................................23\n1.10.8 Metallurgical Examination of Cast Iron Water Pipe ...................................................23\n1.11 Public Awareness ...................................................................................................................25\n1.11.1 Regulatory Requirements ............................................................................................25\n1.11.2 Con Edison Public Awareness Program ......................................................................26\n1.11.3 Con Edison Public Awareness Program Leak Recognition and Response .................27\n1.11.4 Con Edison Public Awareness Program Effectiveness ...............................................27\ni\n\n<<<PAGE 5>>>\n\nNTSB Pipeline Accident Report\n1.12 Regulatory Oversight .............................................................................................................28\n1.12.1 Federal Oversight .........................................................................................................28\n1.12.2 New York State Oversight ...........................................................................................29\n1.12.3 Comparison of Federal and State Regulations .............................................................30\n1.13 Postaccident Activities ...........................................................................................................32\n1.13.1 FDNY Fire Investigation .............................................................................................32\n1.13.2 Con Edison Heat Fusion Procedure Upgrade ..............................................................32\n1.13.3 Sewer Inspection and Excavation ................................................................................32\n1.13.4 Gas Pressure Tests .......................................................................................................33\n1.13.5 Examination of Area Below the Pavement ..................................................................33\n1.13.6 New York City Underground Infrastructure Working Group .....................................36\n1.13.7 Use of 911 for Gas Odor Calls ....................................................................................37\n1.13.8 Plastic Fusion Welder Qualifications ..........................................................................38\n1.13.9 New York Public Service Commission Notice of Proposed Rulemaking ...................40\n2 Analysis ......................................................................................................................................41\n2.1 Water Main Damage ................................................................................................................41\n2.2 Sewer Damage .........................................................................................................................41\n2.3 Gas Main and Service Tee .......................................................................................................42\n2.3.1 Service Tee Failure Examination ...................................................................................42\n2.3.2 Fusion Joint Operator Qualification ..............................................................................44\n2.4 Con Edison Emergency Call Response ....................................................................................45\n2.5 Con Edison Public Awareness Program ..................................................................................46\n2.6 Alignment of State and Federal Gas Pipeline Regulations ......................................................46\n3 Conclusions ................................................................................................................................48\n3.1 Findings....................................................................................................................................48\n3.2 Probable Cause.........................................................................................................................49\n4 Recommendations .....................................................................................................................50\nAppendix A. Investigation ...........................................................................................................52\nAppendix B. Timeline ..................................................................................................................53\nReferences .....................................................................................................................................55\nii\n\n<<<PAGE 6>>>\n\nNTSB Pipeline Accident Report\nFigures\nFigure 1. Buildings on west side of Park Avenue between East 116th and\nEast 117th Streets before March 12, 2014, accident. ...................................................................... 1\nFigure 2. Buildings 1644 and 1646 Park Avenue in New York City after\nMarch 12, 2014, explosion.............................................................................................................. 6\nFigure 3. Overhead view of accident block. .................................................................................. 7\nFigure 4. Gas main, water main, and sewer main positions below road at gas\nservice tee location. ......................................................................................................................... 8\nFigure 5. Sewer damage on south-facing video frame from October 2006 inspection. .............. 11\nFigure 6. Exemplar gas main with service tee welded to it ........................................................ 13\nFigure 7. Saddle fusion machine................... .............................................................................. 13\nFigure 8. Exemplar service tee showing cutter and seal cap. ...................................................... 15\nFigure 9. Accident 8-inch-diameter HDPE service main (top) and HDPE service tee\nat left of 2-inch-diameter HDPE service pipe (bottom). ............................................................... 16\nFigure 10. Installed configuration of accident 2-inch-diameter service pipe and\n8-inch-diameter main. ................................................................................................................... 16\nFigure 11. Exemplar saddle fusion joint service tee assembly with a round base\nportion and showing three distinct fusion beads. .......................................................................... 17\nFigure 12. Inlet face of exemplar service tee that was pressed against heater\nadapter plate (heating iron) preheated to about 500°F but not fusion joined to a pipe. ................ 18\nFigure 13. Fracture faces after drop weight tests on exemplar service tee inlet fusion\njoint from the sound fusion joint (left) and the oil-contaminated fusion joint (right). ................. 19\nFigure 14. Upper fracture face (saddle end) recovered from accident saddle fusion joint ......... 20\nFigure 15. Fusion joint on 8-inch gas main recovered from accident site. .................................. 20\nFigure 16. Exemplar saddle fusion joint service tee assembly with a round base portion\nshowing three distinct fusion beads. ............................................................................................. 22\nFigure 17. Mating fracture faces of 12-inch cast iron water main. .............................................. 24\niii\n\n<<<PAGE 7>>>\n\nNTSB Pipeline Accident Report\nFigure 18. North water main pipe segment fracture face showing regions of graphitic\ncorrosion that appear as dark features adjacent to outer and inner surfaces. ................................ 25\nFigure 19. Schematic comparing federal and New York regulatory definitions of\nservice line leading to a gas meter inside a building. ................................................................... 31\nFigure 20. Water containing fluorescent dye flowing into sewer main through damaged\narea in east side of sewer main as shown in a video frame from March 28, 2014, inspection. .... 33\nFigure 21. Circumferential crack in exposed 12-inch cast iron water main near 8-inch\nHDPE gas main. ............................................................................................................................ 34\nFigure 22. Eight-inch HDPE gas main, detached service tee, and service line\nin front of Building 1642 with closeup of detached service tee. .................................................. 35\nFigure 23. Voids and gaps in ground beneath sidewalk in front of Buildings 1642\nand 1644. Inset photo shows void above brick basement foundation at Building 1644. .............. 36\niv\n\n<<<PAGE 8>>>\n\nNTSB Pipeline Accident Report\nTable\nTable 1. Injuries. ..............................................................................................................................5\nv\n\n<<<PAGE 9>>>\n\nNTSB Pipeline Accident Report\nAcronyms and Abbreviations\nAPI American Petroleum Institute\nASTM ASTM International\nBuildings 1642, 1644, 1646 1642, 1644, and 1646 Park Avenue\nCall Center Con Edison Customer Service Call Center\nCFR Code of Federal Regulations\nCon Edison Consolidated Edison Company of New York, Inc.\nCSR customer service representative\nDOT US Department of Transportation\nFDNY New York City Fire Department\nFDS Manhattan Fire Dispatch System\nGERC Gas Emergency Response Center\nHDPE high-density polyethylene\nmechanic gas distribution service mechanic\nMetro-North Metro-North Railroad\nNGA Northeast Gas Association\nNTSB National Transportation Safety Board\nNYCDEP New York City Department of Environmental Protection\nNYCDOT New York City Department of Transportation\nNYCRR New York Codes, Rules and Regulations\nNYPD New York City Police Department\nNYPSC New York Public Service Commission\nNYSDPS New York State Department of Public Service\nOPS Office of Pipeline Safety\nPHMSA Pipeline and Hazardous Materials Safety Administration\npsig pounds per square inch, gauge\nvi\n\n<<<PAGE 10>>>\n\nNTSB Pipeline Accident Report\nExecutive Summary\nOn March 12, 2014, about 9:30 a.m. eastern daylight time, two adjacent multiuse\nfive-story buildings were destroyed by a natural gas-fueled explosion and resulting fire. The\nbuildings were situated on the west side of Park Avenue between East 116th Street and\nEast 117th Street in the East Harlem district of the Borough of Manhattan in New York City. The\nviolent explosion damaged buildings on the east and west sides of Park Avenue and along\nEast 116th and East 117th Streets. The Metro-North Railroad suspended rail service for about\n7 1/2 hours on the elevated railway along Park Avenue because of debris from the explosion on\nthe track. Eight people died, more than 50 people were injured, and more than 100 families were\ndisplaced from their homes as a result of this accident. The cost to Consolidated Edison\nCompany of New York, Inc. (Con Edison), of equipment damages, emergency response\nactivities, remediation, and replacement exceeded $1.9 million.\nThe National Transportation Safety Board determines that the probable cause of the\naccident was (1) the failure of the defective fusion joint at the service tee, installed by\nConsolidated Edison Company of New York, Inc., in 2011, that allowed natural gas to leak from\nthe gas main and migrate into the building where it ignited and (2) a breach in the sewer line that\nwent unrepaired by the New York City Department of Environmental Protection since at least\n2006 that allowed groundwater and soil to flow into the sewer, resulting in a loss of support for\nthe gas main, which caused the line to sag and overstressed the defective fusion joint.\nThe accident investigation focused on the following safety issues:\n Adequacy of Con Edison’s quality assurance and quality control procedures for\njoining plastic pipes. A Con Edison contractor installed the service tee in 2011 using\na Con Edison heat fusion procedure for plastic pipe. Postaccident examination of the\nseparated service tee joint showed fracture features indicating that the surfaces were\ncontaminated, resulting in a weak joint. Review of the Con Edison plastic pipe fusion\nprocedure revealed that some industry-standard steps, such as cleaning the surface\nwith alcohol, were omitted. In addition, inspection of the fusion joint revealed\ninconsistent bead sizes.\n Effectiveness of Con Edison’s public awareness program. Con Edison had an\nextensive public awareness program that included informing the public and gas\ncustomers to call Con Edison in the event of a suspected gas leak. This information\nwas included in customer billings, in newspaper advertisements, and in flyers posted\nin apartment buildings. However, the investigation found that people who said they\nsmelled gas the day before the accident did not call Con Edison, the fire department,\nor 911.\n Adequacy of Con Edison’s gas odor report response. About 25 minutes before the\naccident, Con Edison received a call from a resident of an adjacent building who\nreported a gas odor inside and outside of his residence. He said the gas was coming\nfrom one of the accident buildings. During the call, the Con Edison customer service\nvii\n\n<<<PAGE 11>>>\n\nNTSB Pipeline Accident Report\nrepresentative’s computer stopped responding, which delayed the notifications.\nAlthough a gas service mechanic was dispatched, the fire department was not notified\nas required by Con Edison’s response procedure.\n Effectiveness of the New York City Department of Environmental Protection\nsewer integrity program. Investigators discovered a large breach in the sewer main\nnear the destroyed buildings that had gone unrepaired for more than 8 years. They\nalso learned of recurring major street repair work in the vicinity of the sewer breach\nover several years. This work included a repair that was made a few days before the\naccident to correct significant ground settling below the pavement in the vicinity of\nthe gas main and building service lines.\n Effectiveness of federal and state oversight. The state pipeline safety program\ncertifications in Title 49 United States Code section 60105(a) allow states to inspect\nand enforce intrastate pipeline safety. The state must adopt the minimum federal\nregulations for pipeline safety. Examination of the New York state pipeline safety\nregulations revealed that they are less stringent than the federal regulations in two\nareas: definition of service line and pipeline pressure testing. These deficiencies were\nnot identified by the Pipeline and Hazardous Materials Safety Administration during\nstate program recertifications.\nAs a result of this investigation, the National Transportation Safety Board makes safety\nrecommendations to the New York State Public Service Commission, the City of New York, and\nConsolidated Edison Company of New York, Inc.\nviii\n\n<<<PAGE 12>>>\n\nNTSB Pipeline Accident Report\n1 Factual Information\n1.1 Accident Synopsis\nOn March 12, 2014, about 9:30 a.m. eastern daylight time, two adjacent multiuse\nfive-story buildings were destroyed by a natural gas-fueled explosion and resulting fire. The\nbuildings were situated on the west side of Park Avenue between East 116th Street and\nEast 117th Street in the East Harlem district of the Borough of Manhattan in New York City.\n(See figure 1.)\nFigure 1. Buildings on west side of Park Avenue between East 116th and East 117th Streets\nbefore March 12, 2014, accident.\nThe violent explosion damaged buildings on the east and west sides of Park Avenue and\nalong East 116th and East 117th Streets. The Metro-North Railroad (Metro-North) suspended\nrail service on March 12 for about 7 1/2 hours on the elevated railway along Park Avenue\nbecause of debris from the explosion on the track.\nEight people died, more than 50 people were injured, and more than 100 families were\ndisplaced from their homes as a result of this accident. Although the amount of natural gas\nreleased from the distribution system could not be accurately estimated, Consolidated Edison\nCompany of New York, Inc. (Con Edison) stated that in the worst-case scenario, at the operating\npressure of 8 inches of water column (about 1/3 pound per square inch, gauge [psig]), up to\n1\n\n<<<PAGE 13>>>\n\nNTSB Pipeline Accident Report\n158 cubic feet of natural gas could be released per minute through the 1 7/8-inch-diameter hole\nthat was tapped into the 8-inch-diameter high-density polyethylene (HDPE) gas main in front of\nBuilding 1642. The cost of equipment damages, emergency response activities, remediation, and\nreplacement to Con Edison exceeded $1.9 million.\n1.2 Accident Site\nThe building at 1644 Park Avenue (Building 1644) was a five-story walk-up built about\n1898. It contained the Spanish Christian Church, which occupied the basement and the first two\nfloors, and three residential floors with two apartments on each floor.1 This building had an\noil-fired heating system, with natural gas used for cooking. Five fatalities occurred in this\nbuilding. The building at 1646 Park Avenue (Building 1646) also was a five-story walk-up built\nabout 1898. This building contained a piano store that occupied the basement and the first floor\nand four residential floors with two apartments on each floor; one of the eight apartments was\nvacant. Three fatalities occurred in this building. The building at 1642 Park Avenue\n(Building 1642) had four stories and four apartments and was built in 2011. It was significantly\ndamaged in the explosion.\n1.3 Gas Odor Calls to Con Edison\nAbout 9:06 a.m. on March 12, a resident of Building 1652 called the Con Edison\nCustomer Service Call Center (Call Center) to report a natural gas odor.2 The caller’s building\nwas north of and next to Building 1646. (See figure 1.) The caller reported smelling gas both\ninside and outside and said that the odor was coming from “another building … right next to\n[this one].” The caller further described the odor as coming from a building with a piano store.\nDuring the call, the Call Center computer system stopped responding to the customer service\nrepresentative’s [CSR] entries), and the CSR put the call on hold several times. The call took\nabout 6 minutes to complete. The CSR told the caller to evacuate immediately, and added, “we’ll\nbe there within 45 minutes.”\nAt 9:12 a.m., the CSR called the Con Edison Gas Emergency Response Center (GERC)\nand spoke with a dispatcher about the gas odor report. Con Edison’s Gas Operations Emergency\nResponse Plan describes GERC in section 3.2. a. (4) (Con Edison 2014):\nThe GERC is responsible for the safe and reliable operation of the company’s gas\ndistribution system. Activities include dispatching and directing gas crews in\nresponse to gas odor reports and other gas system problems, and monitoring\nexcavation activities in the vicinity of gas transmission mains and\nidentifying/initiating contingency plans. The GERC coordinates emergency\nresponse efforts associated with incidents on the gas distribution system and\n1 The New York City Fire Department (FDNY) determined that the explosion and fire originated inside of\n1644 Park Avenue, in the Spanish Christian Church on the first and second floors, when a mixture of natural gas and\nair was ignited by an unidentified ignition source (FDNY 2014).\n2 See appendix B for a timeline of the activities of Con Edison and first responders beginning with the call to\nCon Edison.\n2\n\n<<<PAGE 14>>>\n\nNTSB Pipeline Accident Report\nimplements the incident command system. GERC is responsible for notifying and\nreceiving information from appropriate federal, state, or local agencies, including\nfirst responders, regarding gas distribution system status. The GERC maintains\nthe Emergency Contact and Notification list for Gas Operations and first\nresponders. …\nThe Con Edison computer system was designed so that data from the call taken by the\nCSR—time, location, content—was transmitted to the GERC computer system. In addition, the\nCon Edison procedure required the CSR to call GERC to confirm that the key information from\nthe report was received and correctly understood as it had been entered into the computer. On\nMarch 12, when the CSR called GERC after receiving the gas odor call from Building 1652, she\ntold the dispatcher that her computer was down, but then she noted that it was back up and said\nthat she was entering a ticket for an indoor gas leak.3 The dispatcher asked the CSR to call back.\nAbout 9:13 a.m., the CSR made a second call to GERC to confirm receipt by the\ndispatcher of the indoor gas leak ticket that she had just entered and to confirm the key\ninformation provided by the caller. During this call, the CSR gave the address and details of the\nticket to the dispatcher. The CSR indicated that the caller had stated that there was a smell of gas\nboth inside and outside. The dispatcher told the CSR that another ticket, for a report of gas odor\noutside, should be entered into the computer.\nAbout 9:15 a.m. the dispatcher called a gas distribution service mechanic (mechanic) who\nwas about 4 miles away from the location of the gas odor report. The dispatcher told the\nmechanic that he would receive two tickets for gas odor, one for inside the building and one for\noutside.\nAbout 9:16 a.m. the CSR made a third call to the GERC dispatcher to follow up the\noutside gas leak ticket. The CSR told the dispatcher that the computer system was “freezing” and\nasked if the ticket for Building 1652 had been received. The dispatcher said that it had not.\nAbout 9:19 a.m. the dispatcher called the New York City Fire Department (FDNY) to\nreport the gas odor at Building 1652. During the call, the dispatcher said, “Hold up, no, sorry,\nhold on one second, hold on, hold on, I’ll call you right back.” After this call, GERC made no\ncalls to the FDNY before the buildings exploded at 9:30 a.m.\nAbout 9:39 a.m. the GERC operations manager called the Manhattan Fire Dispatch\nSystem (FDS), which is part of the FDNY, to ask whether the FDNY had received any reports of\nfire at the Park Avenue location of the gas odor report. The FDNY operator said that there was a\nreport of a “building that exploded” at Park Avenue and 114th Street, it had “collapsed, and it’s\non fire.” About 9:46 a.m. the operations manager called all Manhattan gas operations personnel\nto request that all available personnel respond to the explosion location.\n3 A ticket is a work order for a mechanic to investigate a gas odor report.\n3\n\n<<<PAGE 15>>>\n\nNTSB Pipeline Accident Report\nThe GERC operations manager called a gas construction planner about 9:55 a.m. to\ndiscuss where to dig fire banks to stop the flow of natural gas to the two destroyed buildings.4\nThe operations manager told the planner that he would call back once he determined the distance\nfrom the curb line to the gas mains. About 10:08 a.m. he called the New York State Department\nof Public Service (NYSDPS) to report where the fire banks would be located. Fire bank\nexcavation began in three locations about 10:45 a.m.\nBy 1:44 p.m. Con Edison had completed the emergency excavations and the necessary\np","truncated":true,"body_characters":146796}