Class

Test

MO
Non-flammable (Calorific value < or = to 2508 kJ/kg)

UNE 23.102-90 Reaction to fire test for building materials
Non combustibility test

M1
Non-flammable (Calorific value > or = to 2508 kJ/kg)

·  Rigid materials / Materials on rigid substrates (flooring and finishes) of all thickness / flexible materials thicker than 5 mm:
UNE 23.721-90 Reaction to fire test on building materials
Radiation test

·  Flexible materials with a thickness < or = to 5 mm:
UNE 23.723-90 Reaction to fire test on building materials
Electrical burner test

Complementary tests

·  Materials which are not intended to be placed on rigid substrate:
UNE 23.724-90 Reaction to fire test on building material
Speed of the spread of flame test

·  Melting materials:
UNE 23.725-90 Reaction to fire test on building materials
Dripping test with electrical radiator

·  Floorings:
UNE 23.726-90 Reaction to fire test on building materials
Radiant panel test

M2
Low flammability

M3
Moderately flammable

M4
High flammability