In order to make comparisons between different materials, any flammability tests should provide results that can be expressed as numbers. Given the mentioned factors that influence flammability, there are numerous tests that are conducted on materials. The following are the mentioned factors that influence fabric flammability.
Material: Each fiber material has its own unique combustion characteristics, such as polyester combustion with droplet phenomenon. Different moisture regain of different raw materials also affect the heat absorption during combustion. The exothermic order and the total amount of heat resulting from the combustion of the six materials, polyester, acrylic, nylon, cotton, linen, silk and wool, has been studied.
The results show that the order of heat release of different materials in the combustion test is polyester> silk> cotton> hemp> silk> acrylic> nylon 6. The total amount of fabric mass exotherm is: cotton> acrylic> nylon 6> polyester> hemp> wool> silk. This is because the natural fiber has a high moisture regain. The absorption of heat in this stage is mainly used for evaporation of moisture of the fabric itself, and heat starts to release after the fabric temperature reachs the ignition. Synthetic fiber's moisture regain is low, absorbing less heat used to evaporate moisture. This is also related to the adequacy of the fabric's burning.
Fabric organization and weight: when fabric material is consistent, the shorter the average floating length of fabric, the heavier fabric weight, the higher fabric oxygen limit.
Fabric flame retardant finishing: after the fabric is finished by flame retardant finishing, the flammability reduces.
Test conditions: The size of the test box affects the oxygen content of the combustion environment. Test the distance between the flame and the specimen, the length of the flame affects the way the fabric is ignited, and the amount of ignition time directly affects the severity of the burn. Therefore, the test for the burning performance of the fabric should use the standard instrument, in accordance with the provisions of the standard to ensure the accuracy of the test results.