What evaluation criteria of fabric FR properties?
2015-08-06 15:03 | writer: admin
There are two ways to evaluate fabric flammability: one is ignition ( the level of ignition point), which indicates the degree of difficulty of fabric is on fire; the other hand, flammability of fabric(flame retardant).
There is two criteria to assess the FR performance of fabric:
One is to judge from the burning rate of the fabric: that is finishing fire-retardant fabric contact with the flame for a certain time according to the method prescribed , then remove the flame, measured fabrics continue to flaming combustion time and flameless combustion time, and the extent of the fabric being damaged. The shorter of flaming combustion time and flameless combustion, the lower level was damaged, that will means the FR performance of fabric is better; on the contrary, it means that flame retardant performance of fabric is not very good.
Another is adjust through the oxygen index (also known as polar oxygen index) method: Fabric combustion requires oxygen, the oxygen index (LOI) is required for the expression of fiber burn oxygen, so you can determine by measuring the oxygen barrier fabric index combustion performance, the higher the index remained higher oxygen concentration of oxygen needed for combustion, that means the more difficult to burn. The index can be used to maintain the required sample Candle burning when the oxygen minimum volume percent nitrogen, oxygen gas mixture is represented: LOI = oxygen concentration / (oxygen concentration + nitrogen concentration) × 100%,when the oxygen index is less than 20%, it belongs to flammable fiber,when oxygen index is 20% to 26%, is a combustible fiber; if oxygen index is between 26 to 34 percent,it is a difficult flame retardant fiber; if oxygen index is more than 35% ,it is non-combustible fibers.