Wilhelm Jost Institut Förderverein e.V.

Ignition temperature


The ignition temperature is the lowest temperature of a hot surface at which the inflammation of an inflammable material as gas/air or steam/air mixture occurs. The ignition tempeature is determined under prescribed test conditions.


Testing Method:

according to DIN EN 51 794 in a pre-heated Erlenmeyer flask


Safety-relevant meaning:


The ignition temperature is needed for the new material registration and serves for the organization of inflammable materials into temperature classes according to DIN EN 50 014. Electrical and non electrical equipment only have to be used in highly combustible ranges if they are certified in accordance to the following table for the appropriate temperature class.


Ignition temperature according to DIN EN 51 794

Temperature class according to DIN EN 50 014

Maximum surface temperature

IT > 450 °C

T 1

450 °C

300 °C < IT < 450 °C

T 2

300 °C

200 °C < IT < 300 °C

T 3

200 °C

135 °C < IT < 200 °C

T 4

135 °C

100 °C < IT < 135 °C

T 5

100 °C

85 °C < IT < 100 °C

T 6

85 °C


In general it is to be noted that the ignition temperature strongly depends on operational environmental influences.