Clothing Textiles sold in the US must all pass this standard flame spread test.  This test does not offer the opportunity to claim a textile is flame resistant.  That is conferred by ASTM F2502 or other large scale testing but all clothing is required to be tested to this standard and to pass to be sold in the US.

Test used in textiles industry for all clothing. The test procedure places a sample 15×150 mm in a holder after it is dried in a 100°C oven for 30 min. The test is performed at a 45-degree angle in the test apparatus. A specific height of flame from a specific gas source impinges on the fabric for one second and the flame spread time is measured.

Class 1 – Normal flammability: these textiles fully meet the highest requirements of the standard and are acceptable for use in clothing.

Class 2 – Intermediate flammability: these textiles are more flammable than Class 1 but still meet the requirements of the standard and are acceptable for use in clothing. This classification only applies to raised-fiber surface textiles.

Class 3 – Rapid and intense burning: These textiles are dangerously flammable and cannot be used for clothing in the U.S. These samples fail to meet the requirements of the standard.