Process safety - Fires in insulation

Many fires, some of them devastating, have occurred due to fires caused by lube oil/ thermic fluid soaked insulation.
An article by Don Drewry and Dominique Dieken mentions the following on lube oil fires in steam turbines:
"Most steam turbines use mineral oil with a flash point ranging between 375 F and 500 F (190 to 260 Deg C). When sprayed onto a hot surface the oil will self-ignite at about 675 F (357 Deg C). Pressurized supply oil lines, if damaged, can compound the problem as atomized oil would be sprayed onto hot surfaces. Either self-ignition or a nearby ignition source can result in a three-dimensional fire at the bearing or lube oil piping with the burning oil flowing downward and collecting at ground level in the form of a pool fire.
The flame temperature of a lube oil fire, up to 2,100 F (1148 Deg C), can cause heat to be transferred to various turbine components through conduction, convection and radation. If there is flame impingement, the surface temperature of any exposed area can be expected to reach 2,100 F (1148 Deg C) within five minutes. As the temperature rises the turbine generator components expand at different rates. If this expansion is prevented because of geometric limitations, thermal stresses occur, which can exceed the yield strength of the materials and cause the components to fail.When a fire occurs the heat rising from the fire can also collect at the ceiling. If this happens the temperature can rise above 900 F and failure of the roof can occur. Likewise, a pool fire at ground level will quickly involve control and power cables beneath the turbine deck. Any extended exposure to heat will also damage the turbine's concrete pedestal".
Read the article in this link.

Fires have also occurred in reactors with coils that use thermic fluids to heat/cool the reactor. A presentation by John Griffiths mentions the following:
"Gas phase or liquid phase reaction?
Exothermic reaction of the liquid occurs as a result of oxidation by atmospheric oxygen. The liquid is dispersed over an enormous surface area within the structure.
How close to classical “thermal ignition”?
It all depends: if the fluid is very involatile at a typical temperature for exothermic reaction then the problem reduces to “thermal ignition”.The principles of lagging fires are the same – a breakdown of the balance between heat release and heat loss leads to thermal runaway.
So what are the distinctions from “thermal ignition”?
1.Vaporisation of the liquid can occur. It may be sufficiently rapid that most is dispersed, preventing self-heating taking place.
2.There can be an depletion of oxygen within the porous structure as a result of fuel vapour movement, but not necessarily enough to preclude oxidation.
3.The endothermic effect of vaporisation, contributes to the “heat loss” component.
4.Condensation is possible elsewhere in the structure (“giving back” the enthalpy of vaporisation).
Studies prior to ours erred towards involatile liquids so the most important distinctions (and features) of lagging fires were masked.
Is autoignition temperature of the fluid (AIT) relevant?
No (other than giving some indication of how reactive a substance might be)".
See the complete presentation in this link.