What are SFI and TPP Ratings?
SFI Ratings are determined by the results of several tests conducted on racing suits for fire retardant capabilities and Thermal Protective Performance (TPP). The standard spec for racing suits is 3.2A.
What does this mean to you, the consumer? It means that you have a way to differentiate between quality-assured products and untested products. A driver suit that is certified to meet SFI spec has been laboratory tested and has passed the requirements of the tests. Those manufacturers who certify their products as SFI approved demonstrate their commitment to providing the highest levels of safety for their customers.
TTP ratings indicate the length of time the person wearing the garment can be exposed to a heat source before incurring a second degree or skin-blistering burn. The higher the value, the longer before you will incur a second degree burn.
Other tests conducted to determine SFI ratings are the After-Flame test (indicates how long the garment material takes to self-extinguish following the application of a direct flame), Thread Heat Resistance, Zipper Heat Resistance, and Multiple Layer Thermal Shrinkage.
It is important to understand that SFI Rating do NOT represent the number of fabric layers in the garment.