THE NFPA 701 AND EN 1021-1&2 TESTS
It may not be probable to turn fabrics, textiles, or films utterly resistant to fire. However, it is possible to improve their fire propagation performance through chemical treatment. Chemically treated natural fibre textiles have reduced flammability and smouldering rates. Flame retardant chemicals are added to synthetic fibres and plastic films, reducing their flame spread rate.
Using textiles and films with reduced flame propagation in high-risk occupancies such as theatres, hotels and hospitals is specified in national codes or regulations. The authority having jurisdiction determines the relevant fire performance tests for such materials.
Fire retardant textiles and films are used for curtains, draperies, decorative materials, protective coverings, temporary enclosures for greenhouses, tents, and tarpaulins and as outer upholstery covers.
The NFPA 701
Test methods 1 and 2 of the NFPA 701 standard investigate the flame propagation properties of textiles and films. The two methods are not used to assess whether the fabric/material tested is fit for use in personal protective equipment.
Test method 1 applies to materials with areal densities less than or equal to 700g/m2, including:
1. Fabrics used in window treatment, such as curtains and draperies
2. Single-layered fabrics
3. Multi-layered curtains and draperies whose layers are held together by means such as sewing
4. Combustible artificial decorative vegetation
Test method 2 applies to materials with areal densities of more than 700g/m2, including:
1. Fabrics of areal densities higher than 700 g/m2
2. Decorative materials except fabrics satisfying the requirements of method 1
3. Vinyl-coated fabric blackout linings and draperies that are lined with vinyl-coated fabric blackout lining
4. Plastic films
5. Fabrics used in awnings, banners, or tarps assembly
6. Fabrics used in the assembly of tents (temporary or permanent) and tent accessories, including drops, sidewalls, floor coverings and tarpaulins
7. Combustible artificial decorative vegetation of areal densities higher than 700 g/m2
The EN 1021-1 & 2
These test methods evaluate the ignitability of a combination of materials used in upholstered seating. Such materials include upholstery covers/fabrics, fillings, and padding/cushions. These tests assess the fire performance of a combination of materials; they do not assess the ignitability of specific finished furniture. The tests indicate the fire performance of finished furniture incorporating the tested materials.
With both tests, an assembly of the upholstery materials is mounted on a test rig in a way to simulate a typical chair, forming a junction between a seat and backrest or a seat and arm. A smouldering cigarette and butane flame are used as the ignition sources for EN 1021-1 and EN 1021-2 tests, respectively. The flame source is positioned axially along the junction in the assembly. In both tests, evidence of progressive smouldering and flaming ignition is observed.
In conclusion, the NFPA 701 test methods apply to fabrics/textiles, plastic films, decorative materials, and combustible artificial decorative vegetation. On the other hand, EN 1021-1&2 tests are suitable for upholstered furniture tests. The results of these tests pertain to the performance of the assembly, not the individual materials tested in the rig.