FLAME PERSISTENCY AND PROPAGATION TEST APPARATUS.
Model : PolyNorme 504.
The flame persistency test according to NF P 92-504 is a reaction to fire complementary test for M classification of building and fitting materials.
It is used for flexible and rigid materials of any thickness which develop holes without inflammation or with short time inflammation during the main test (electrical burner test according to NF P 92-503 or radiation test in an epiradiator cabinet according to NF P 92-501). In that case, the flame persistency test becomes the deciding test for M classification of materials.
In principle, if there is no flame persistency after burner withdrawing, the material can be M1 classified.
In case of flame persistency after burner withdrawing, the M2 or M3 classification will
be made depending on whether the duration of inflammation is ≤ 5 s or > 5 s. In case of inflamed or not dripping, the dripping test (NF P 92-505) is carried out.
The flame propagation test is performed with the same apparatus and on the same size test pieces as for the flame persistency test ; it is used for M4 classification of flexible and rigid materials of any thickness.
A material will be classified M4 if it doesn’t enter in any of the M1, M2 or M3 categories at the conclusion of the main test, or of the flame persistency test, and if during the flame propagation test, it is noticed a continuous flame propagation on 250 mm length at a speed
lower than 2 mm per second.