Ignition (Autoignition) Temperature 2 : The minimum uniform temperature required to initiate or cause self-sustained combustion of a solid, liquid, or gaseous substance (independent of any other ignition source)
EESiFlo North America, Terminology and Glossary: Explosion Proof & Hazardous Areas, Pennsylvania, USA 2002, flowmeterdirectory.com/flowmeter_terminology, (Mrtm/ Explo Proof and Haz Areas - Amer) {561}