PROPANE GAS LEAK IN VEHICLE RESULTS IN FLASH FIRE
A number of vehicles are converting to propane fuel as an economy measure. However, the safety aspects of this trend could have implications for fire fighters and investigators.
Six hours after a new 1982 propaneoperated sedan was put in service at the Audubon, N.J., Police Department, vapors in the passenger compartment ignited, seriously injuring Corporal Larry Nicely, the police officer operating the vehicle.
The police department acquired the vehicle last October and immediately had it equipped with a dual fuel system so that the car could be operated with either gasoline or propane.
On Oct. 18, after fueling the car with propane, Nicely drove about 100 yards from the main fill tank and stopped to check the vehicle’s operating features. Since the portable radar would be operated from the car’s cigarette lighter. Nicely pushed in the lighter at the center of the dashboard.
There was an instant explosion and the interior of the car burst into flames. Unable to open the door, Nicely escaped through the open window on the driver’s side of the car.
Nicely reported the incident and requested assistance via his portable radio. An alarm was transmitted to the Camden County Fire Alarm Center at Lakeland. Two pumpers, one from the Audubon Fire Department under the command of Chief lack Bell, and the other from Defender Fire Co., Audubon, under the command of Captain Greg Murphy, were dispatched.
Both units stretched 1 ¾ -inch lines and extinguished the fire. Bell had the rear trunk forced open and turned off the main feed line leading to the engine compartment.
Nicely was reported to have sustained second and third-degree burns on the right side of his head, neck, face and hands.
Deputy Fire Marshal Philip Baldwin was assigned to conduct an investigation. Following the on-site examination, Baldwin had the vehicle removed from the scene and impounded until a complete investigation could be made.
Sergeant R. McCarthy of the New jersey State Police Emergency Services and Chief Fire Marshal David C. Aaron assisted with the investigation. After again examining and photographing the vehicle, Aaron ordered it removed to the Camden County Complex for confinement and extensive examination.
On Oct. 22, the investigation team was joined by Investigator lames E. Persik of James E. Persik Associates of H.T. Hutchinson, Inc., representatives of the propane industry and the installer of the propane unit in the car.
photos by the author
The main body of fire was concentrated in the vehicle’s passenger compartment, with the dashboard being very badly damaged. Additional examination revealed that the interior rear seat was not properly sealed off from the tank area, and no vents were observed in the tank itself. However, the fire did not extend to the tank or trunk area.
Fire damage also occurred in the engine compartment, but the lower portion of the engine was not involved, verified by the fact that the rubber hoses were still in their original condition. The upper portion of the engine compartment was damaged when heat and fire dislodged the propane tank’s feed line from the liquid petroleum gas converter.
The gasoline fuel line was still intact and did not appear to have any involvement in the fire.
Propane officials insisted that the installation of the propane system was made in compliance with the National Fire Protection Association’s Standard 58, 1979 edition. They further stated that propane gas has an explosive range between 2.4 and 9.6 percent of air, and if gas were present in the car, Nicely would have noticed its odor.
Propane ID Decal
To alert emergency personnel and the public to vehicles with concealed propane tanks, a propane vehicle identification decal has been developed.
The black, diamond-shaped decal with a silver Scotchlite border consists of the word “propane” in 1-inch silver Scotchlite letters for easy nighttime visibility.
The decal should be placed on the outside right rear of the vehicle or as near as practical to the propane tank.
For more information, contact the National LP-Gas Association, 1301 West 22 Street, Oak Brook, III. 60521; telephone (312) 986-4800.
Further examination and pressure tests of the fuel lines and propane tank were needed to determine the cause of the fire. A second investigator, William S. Bigelow, was called in.
Baldwin, Persik and Bigelow met on Nov. 17 to conduct pressure tests.
A low pressure gas test system to check the fill line into the main propane tank showed that when the main fill line was pressurized, there was a definite leak into the high pressure fill line at the coupling. The coupling was discovered to be loose, verified by pouring a liquid solution into the fitting under pressure. This in turn produced air bubbles at the coupler end of the high pressure fill line.
It was concluded from investigation tests that the fire was caused by a propane gas leak in the high pressure fill line at the coupling just prior to the tank. The investigation report stated that the vehicle’s rear seat was not properly sealed off from the tank area as per NFPA standards, allowing vapors to enter the passenger area. Plugging in the cigarette lighter ignited the propane vapors in the passenger compartment, resulting in a flash fire.
An interesting postscript to this incident is that the Audubon Police Department, which has been using propane-operated vehicles for over a year, as well as other police departments in the area that use propane-fueled police cars, plan no changes,