Causes of Ignition

Static ignition statistics must be used with prudence not only because of possible misdiagnosis of the cause of ignition but also because of the way the losses are often grouped together. As discussed in Chapters 5 and 6 the likeli-... 

Earthquakes provide the ultimate test of the storage of incompatible chemicals and are sometimes followed by fires in chemical stores. Very few causes of ignition are found alkali metals halogen oxysalts in conjunction with strong acids and sulphuric or nitric acid and cellulose (wood flooring). These usually then ignite vapours of flammable solvents. 

Based on the information provided in the chart, which cause of ignition is responsible for the most number of injuries in residential fires ... 

The so-called "secondary or after flame which arises from the combination of reaction products of primary flame (such as of CO) with surrounding oxygpn in the air, is also dangerous. Other causes of ignition include any naked flame present in mine hot or inflamed particles ejected from the expl adiabatic compression of the gas by a shock wave at supersonic velocity general adiabatic compression of a body or pocket of gas electric sparks or sparks produced by drills hitting stones (which are sometimes embedded in coal) (Refs 7b, 7c, 16a, 22 31)... 

In the period up to about 1980 it was common practice for senior electrical engineers to determine the various hazardous areas on a site. This was historically due to the fact that electrical power equipment was the easiest to identify as a possible cause of ignition. It would often be the first equipment to be investigated when an incident occurred. 

Although autoignition is the probable cause of ignition in most compressed-air-line fires, other sources are possible. They include heat generated by the oxidation of iron sulfide, other sulfur compounds or carbonaceous deposits which may unexpectedly be present in the line, and friction or static-electricity-generated sparks. 

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