Oil-soaked lagging

Bowes, P. C., Fires in Oil-Soaked Lagging, CP35/74, Garston, Building. Res. Establ., 1974... 

As stated in Preface, the oxidatively-heating behavior of a gas-permeable oxidatively-heating substance, such as sawdust, coal dust or oil-soaked lagging, is also of the TD type. Therefore, it is possible, in principle, to calculate the critical temperature for the spontaneous ignition or Tc for a heap of a gas-permeable oxidatively-heating substance such as sawdust of every wood species, having an arbitrary shape and an arbitrary size, placed in the atmosphere under isothermal conditions, by applying the reduced form of the F-K equation, i.e., Eq. (79) derived in Section 6.2, provided the value of for the shape of the substance is known. 

A combustion characteristic which appears to be outside the usual range of characteristics is spontaneous combustion. This is the phenomenon of the apparently inexplicable bursting into flame or smoke of some substances such as oil-soaked rags or overalls, oil-soaked lagging, hay and straw. The explanation is simple a slow oxidation of the oil gives off heat with the formation of substances with lower molecular weights which also have lower flash points. As the oxidation continues the temperature of the... 

Thermal insulation (or lagging) on plant equipment may become soaked or impregnated witli oils and otlier flanuiuible liquids. When the lagging gets hot, spontaneous combustion can occur. Lagging fires are affected by oil laiks, insulation material, and temperature. Spontaneous combustion occurs only when tlie oil is nonvolatile, since volatile oil evaporates more easily, tlius delaying tlie... 

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