UL94---The fireproof rate for material

​The fireproof mean the material have the property to restrain or delay the burning, and not easy to be burnt.

Most popular rate for fireproof is UL94, which evaluate the ability to extinguish the fire after it is burnt. When select one material, UL rate should satisfy the requirements of part thickness. The thickness and UL rate should be reported together, not just only the UL rate.

UL94 have 12 levels: HB, V-0, V-1, V-2, 5VA, 5VB, VTM-0, VTM-1, HBF, HF-1, HF-2. In these levels, HB is most bottom among them, a progressive increase from HB, V-2, V-1 to V-0