Gasoline Flows After Frost Cracks Breakaway Valve
During extremely cold weather, the Oak Brook, Ill., Fire Department responded to an unusual call. A gasoline station was experiencing a leaking dispensing pump, which could not be explained.
Fuel was pumped to the dispensing pump from an underground tank by a submersible pump inside the tank. On the day of our response, whenever the pumps were turned on, gasoline would leak from beneath the dispensing pump. A visual inspection of the pump and the connecting piping revealed no apparent trouble. A much closer inspection by the Oak Brook Fire Department revealed a leaking break-away valve. It appears that the following chain of events brought about this unique circumstance.
During the preceding few days, the temperatures ranged from about — 20°F at night to daytime highs of about +15°F. Frost beneath the dispensing pump island apparently raised the island approximately ¼ to ½ inch. The pressures developed by this were sufficient to cause the break away valve to separate where the valve and piping connected.
The separation was minor, but sufficient to permit gasoline to escape whenever the pumps were turned on.
It is our belief that many other gasoline dispensing pumps in areas affected by severe cold may develop a similar problem, that of a break in the piping that is insufficient to trip the shut-off valve.
