Standards ressources

M classification (NF P 92-503)

M classification (NF P 92-503)

The M classification allows for the evaluation of a material’s reaction to fire, in other words, its ability to fuel and propagate the fire to which it is exposed. The goal is to prevent the rapid development of a fire.

The performance of the material is assessed according to 5 levels, as follows:

  • Non-combustible, non-flammable (M0)
  • Combustible, non-flammable (M1)
  • Combustible, difficult to ignite (M2)
  • Moderately combustible, moderately flammable (M3)
  • Highly combustible, easily flammable (M4)


At Duflot, we assess the fire behaviour of our non-woven fabrics using an electric burner (NF P 92-503). (NF P 92-503).

For this test, the material is exposed to:

    radiant heat

  • hot gas sweeping across its surface
  • A pilot flame is used to potentially cause ignition.

The product’s performance is assessed based on the following criteria:

  • production of glowing droplets
  • length/width of the damaged sample

Euroclasses (NF EN 13501-1)

This standard defines the classification of construction products (excluding floor coverings) based on their reaction to fire.

Materials are classified into 3 categories:

  • Non-combustible or low combustible: classification A1, A2, and B
  • Combustible: classification C, D, and E
  • Very easily combustible: classification F

These 7 classes are defined based on the thermal potential of the product.

Products resulting from the bonding of one or more non-combustible materials (such as concrete, mineral wool, ceramics, etc.) are considered to belong to class A1 without prior testing (provided that the adhesive content does not exceed 0.1%).

The Single Burning Item (SBI) test is carried out for classes A2, B, C, D, and E (NF EN 13823) to determine additional criteria (indices s and d).

For this, a specimen (consisting of two vertical wings forming a right angle) is exposed to the flame of a 30kW burner for 20 minutes. The material’s performance is then assessed according to the following criteria:

  • Smoke opacity defined by the s index (for "smoke") and divided into 3 categories: s1 (low quantity and speed), s2 (medium quantity and speed), and s3 (high quantity and speed).
  • The formation of droplets or flaming debris characterized by the d index (for "droplets") as follows:
    • Index d0 = no flaming debris or droplets during the first 600 seconds of product exposure.
    • Index d1 = no debris and droplets whose combustion does not last more than 10 seconds during the first 600 seconds of product testing.
    • Index d2 = for materials that are not d0 or d1

Fire Test - TB 117 (American Standard)

This test standard determines the resistance to combustion of materials used in upholstered furniture.

The goal is to produce safe upholstered furniture in the face of dangers associated with cigarettes.

For this, a test is conducted using a seat assembly and a burning cigarette covered with fabric. The cigarette is placed at the junction of the backrest and the seat of the chair.

At the end of this test, the result obtained is either "PASS" or "FAIL".

For the product to be compliant, it must meet the following criteria:

  • No combustion beyond 45 minutes
  • Vertical burn distance less than 51mm
  • No active combustion or flame during the final examination

Fire test - BS 5852 Crib 5 (British Standard)

The purpose of this test standard to assess the ignitability of a combination of materials used in upholstered seating.

For this test, a simulated ignition source is created by placing a small pile of wood (wood stack) containing an alcohol-soaked wick on the sample to be tested.

At the end of this test, the result obtained is either "PASS" or "FAIL".

For the product to be compliant, it must meet the following criteria:

  • The duration of inflammation must be less than 10 minutes
  • The production of smoke, combustion, or incandescence must be less than 60 minutes
  • The burned distance must be less than 100mm
  • The loss of mass must be less than 60g
  • No active combustion or flame during the final examination