Question 653 Deck Safety

The correct answer is D) The ignition temperature is always higher. The flash point is the lowest temperature at which a liquid or solid gives off enough vapor to ignite upon application of an external source of ignition. The auto-ignition temperature is the minimum temperature required for a substance to spontaneously ignite without an external source of ignition. By definition, the auto-ignition temperature is always higher than the flash point, as the substance needs to reach a higher temperature to ignite without an external ignition source. The other options are incorrect because A) the flash point is lower than the auto-ignition temperature, B) the two temperatures are related, with the auto-ignition temperature being higher, and C) the auto-ignition temperature is higher than both the flash point and normal burning temperatures.