Tank Car Fire Advice Offered by Safety Board
As a result of railroad tank cars exploding after derailments that led to fires, the National Transportation Safety Board has issued the recommendation that “in a fire involving several tank cars, a prudent course of action may be the complete evacuation of the area within a radius of 2000 feet” whenever there is insufficient information for evaluation of the situation.
The NTSB urged that fire officers study the situation “as closely as possible” before attempting to extinguish fire in a derailment. The commodities involved in the wreck should be identified as soon as possible so that the officer in charge can determine the risks involved, the fire fighting methods that should be used and whether the fire department has sufficient equipment and extinguishing agents on hand to control the situation.
If enough information is not available, then the area should be evacuated for a radius of 2000 feet, the board advised. The exposure of fire fighters should be kept to a minimum when no other persons and a minimal amount of property are endangered, the NTSB advised. However, the board recognized that variables, such as tank cars burning near hospitals or other buildings that cannot be evacuated quickly, have a bearing on the risks that fire fighters might have to assume.
Research being conducted
The problem of exploding and rocketing tank cars is “potentially reducible by technical changes which are under study,” the NTSB disclosed. Research by the United States Department of Transportation and the railroad industry has been going on since the explosion of liquefied petroleum gas tank cars at Laurel, Miss., January 25, 1969. Three persons were killed and 32 others were injured after 15 tank cars were derailed.
The latest NTSB recommendations followed the Missouri Pacific Railroad derailment at Houston last October 19, when one fire fighter was killed and 37 fire fighters, reporters, photographers and spectators were injured.
In this incident, six tank cars of vinyl chloride, three of fuel oil and one each of acetone, butadiene and formaldehyde, were among the 16 cars that piled up in the derailment area. Vinyl chloride escaped from a 48,000-gallon tank car and immediately ignited, the NTSB explained.
The Houston Fire Department attempted to control the fire with water, and 45 minutes after the derailment, a second car of vinyl chloride exploded, causing the death and injuries. Large sections of this tanker were found about 400 feet from the derailment location.
Crescent City disaster
This accident, the NTSB found, was “markedly similar” to the 15-car derailment at Crescent City, Ill., June 21, 1970, when propane escaped from one of the nine tank cars containing this liquefied petroleum gas. Fire fighters attempted to battle the fire that started immediately after the derailment. Explosions occurred for 1 to 4½ hours after the derailment, and 66 fire fighters, reporters and photographers were injured. Large pieces of tank cars rocketed as far as 1700 feet from the derailment.
Investigations of these and other railroad accidents, the board reported, had two distinguishing characteristics. Several tank cars were piled up against one another, and the fire that enveloped one or more tank cars then impinged on relatively undamaged tank cars containing hazardous materials. The board stated that in railroad accidents involving several adjacent tank cars, the resulting fire substantially increases the likelihood of flareups or explosions.
“The reduction in property damage achieved by fire suppression methods used in past accidents,” the NTSB concluded, “has been generally insufficient compared to the risk assumed of injury and death when acting with inadequate or improper information as to the contents of the tank cars.”