WASHINGTON GAS LIGHT CO

Incident Narrative

ON SUNDAY, FEBRUARY 7, 2016, AT APPROXIMATELY 15:18, WASHINGTON GAS RECEIVED A CALL FROM THE PRINCE WILLIAM COUNTY FIRE DEPARTMENT RELATIVE TO AN OUTSIDE GAS ODOR LOCATED AT 14100 FRANKLIN ST. IN WOODBRIDGE, VA. WASHINGTON GAS PERSONNEL ARRIVED ON SCENE AT 15:31. UPON ARRIVAL, THE WASHINGTON GAS TECHNICIAN HAD EXITED HIS VEHICLE AND WAS APPLYING THE APPROPRIATE PPE WHEN A POSSIBLE LOW ORDER EXPLOSION OCCURRED. THERE WERE NO INJURIES OR FATALITIES AS A RESULT OF THE INCIDENT. AN ODORANT SAMPLE WAS TAKEN AND THE LEVEL OF ODORANT WAS DETERMINED TO BE ACCEPTABLE. RELATIVE TO PART A #13 OF THIS FORM. SELECTING YES WOULD NOT ALLOW THE DATE & TIME TO BE INPUTTED BEFORE THE CURRENT DATE. WG RESPONSE TO PART A #13 IS YES. #13A. 2/8/2016 2100HRS. #13B. CUSTOMER HAS NOT ELECTED TO HAVE NATURAL GAS RESTORED THAT WAS PREVIOUSLY INACTIVE. PART C #3C. READING TUBE CORP. & REVERE TUBING WERE BRANDS USED FOR BARE COPPER SERVICE. WG IS UNABLE TO IDENTIFY WHICH WAS USED FOR THIS SPECIFIC SERVICE. PART D #2F. THE LEAK SIZE (SIZE OF OPENING ON PIPE) WAS UNKNOWN. KNOWN FACTS INCLUDED THAT GAS WAS MIGRATING INTO 14100 FRANKLIN ST, AND THERE WAS A SUFFICIENT CONCENTRATION OF GAS TO RESULT IN AN IGNITION. IN ORDER TO ARRIVE AT AN ESTIMATED AMOUNT OF GAS LOST, THE HOME SIZE WAS FIGURED AT 2,100 SQ. FT., WITH AN ESTIMATED CEILING HEIGHT OF 8 FT. THIS RESULTS IN AN ESTIMATED HOME VOLUME OF 2,100 SQ. FT. * 8 FT = 16,800 CU. FT. AN EXPLOSIVE MIXTURE WOULD EXIST WHEN APPROXIMATELY 5 - 15% OF A VOLUME OF SPACE IS OCCUPIED BY GAS. USING A CONSERVATIVE VOLUME OF 16,800 CU. FT., 10% (MID-RANGE BETWEEN THE LEL AND UEL) OF THE HOME VOLUME WOULD EQUAL 1,680 CU. FT. AT A HEATING VALUE OF APPROXIMATELY 1,040 BTU/CU. FT., THIS WOULD TRANSLATE TO 1,747,200 BTU. AT $3/MMBTU, THIS AMOUNT OF GAS WOULD COST $5.24. IT IS UNLIKELY THAT THE ENTIRE STRUCTURE FILLED WITH 10% OF GAS DUE TO THE LOCALIZED NATURE OF THE INCIDENT. HOWEVER, USING THE ENTIRE HOME VOLUME PROVIDES A CONSERVATIVE ESTIMATE THAT TAKES INTO ACCOUNT SOME CONTINGENCIES SUCH AS GAS THAT MAY HAVE MIGRATED ELSEWHERE (UNDERGROUND, OR ESCAPED THE HOME BEFORE THE IGNITION). PART G # 5. BARE COPPER SERVICE LINE IS NOT COATED.