Product Testing > Notes and Reviews > Flammability Testing > T45B: Flammability - Hot Metal Nut Test
TEST CODE:
:
T45B
TEST METHOD
BS4790
IMAGE
Test Apparatus For Hot Nut Test
SCOPE
Determination of flammability of all types of textile floor coverings.
PRINCIPLE
A heated stainless steel nut is placed on the use - surface of the material to be tested. The times of flaming and of afterglow and the greatest radius of the effects of ignition from the point of application of the nut are measured.
MATERIALS
Three specimens including any backing measuring 300 x 300mm.
TEST PROCEDURE
Heat stainless steel nuts weighing 30 + 2g to 900 + 20oC. Place nut on use surface of sample and remove from specimen after 30 + 2s.
Measure flame extinction time, after-glow/smouldering time or time to reach outer clamping ring.
Also record the radius of the effects of ignition on both use surface and under side of specimen.
ASSESSMENT OF RESULT
Radius of affected area:
Up to 35mm Low radius of effects of ignition. 40 to 75mm Medium radius of effects of ignition.80 and over High radius of effects of ignition.
AMOUNT NEEDED
Single piece one metre square.
SERVICE TARGET
8 days
COST
See Fees list.