Ignition temperature chemical substances, general

Flash Point — This is defined as the lowest temperature at which vapors above a volatile combustible substance will ignite in air when exposed to a flame. Depending on the test method used, the values given are either Tag Closed Cup (C.C.) (ASTM D56) or Cleveland Open Cup (O.C.) (ASTM 093). The values, along with those given below, provide an indication of the relative flammability of the chemical. In general, the open cup value is about 10° to 15 °F higher than the closed cup value. 

Oxidation processes arc, as a general rule, greatly accelerated by a rise in temperature the first effect of the application of heat may be merely to initiate a slow oxidation which soon ceases on the removal of the source of heat but a higher temperature may cause so marked an increase m the rate of the chemical action that the heat produced suffices to maintain the temperature, and the oxidation or combustion will proceed unaided. This temperature at which the process of rapid combustion becomes independent of external supplies of heat is termed the ignition temperature of the substance (see p. 106). Phosphorus does not commence rapid combustion until a temperature of 60° C. is attained hydrogen will combine, albeit excessively slowly, with oxygen already at 180° C., but the reaction is not very appreciable below 400° C., and continuous inflammation does not occur until near... 

Flammable Any chemical substance, liquid or solid, that has a flash point of 100°F or below any solid that can sustain fire and ignite readily any material that can be ignited easily and will burn rapidly Flash point The temperature at which a liquid will generate sufficient vapors to promote combustion. Generally, the lower the flash point is, the greater the danger of combustion is... 

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