History 5 Insufficient Sprinkler Density

An electrical surge resulted in off-ratio metering of the reactants or poor mixing. The foam was cooled in an envirofoam chamber. A defective section was noted and the operator was instructed to cut out the defect and place the bun outdoors. A short time later, it was discovered that the defective bun had not been moved outdoors, although it showed no signs of smoking or discoloration. An exothermic reaction continued until it autoignited. 

The dry pipe system was probably too slow in operation and did not provide a density sufficient to extinguish the fire. The new system was designed for a sprinkler density of 0.6 gpm/ ft (24 Ipm/m ) which was more than three times the original design density. 

Escalation occurred because of poor fire protection and poor spacing. 

Procedures for abnormal events need to be followed and reasons explained. 

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