Supplement 2.2:: Properties of Oil (2/2)

Following an oil spill, a large proportion of the substances of content of the oil evaporates and is distilled. The amount of oil decreases and flammable vapours form. The fate of an oil spill and the vapours that form also depends on the temperature of the oil. There are two critical temperatures: the Flash Point and the Fire Point.



The flash point of a flammable liquid is the lowest temperature at which it has developed enough combustible vapour that it can be ignited. However the vapour may cease to burn when the source of ignition is removed.

The vapour evaporating from oils is more or less explosive, depending on the oil's flash point.

The fire point is the temperature at which the vapour of a flammable substance continues to burn after being ignited.
burning of floating oil
Burning of floating oil as a measure of oil spill control.
Photo: ITOPF

The flash point is used to determine the transportation and storage temperature requirements of oils.

Question:

Which of the oils below would you judge to be more suitable for transport on the ocean in terms of safety?

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flash and fire point of two different kinds of motor oil
Flash and fire points of two different kinds of motor oil.