The device is used to test materials for protective clothing at medium and high heat flux densities. Ittests how the materials behave and change when exposed to heat. The results of the test are a part of the classification of the materials used.

The specimen is exposed to a defined heat flux generated by silicon carbide heating rods. In method A, changes are noted after a specified time of heat exposure. Method B measures how long it takes for a temperature increase of 12 oc and 24 oc to occur behind the specimen.