How many grades are there in the plastic block? How to divide?
Flame retardant grade bottom HB:UL94 CSA and C22.2 No 0.17 standard, requirements for 3 to 13 mm thick sample, the burning rate is less than 40 mm per minute; less than 3 mm thick sample, the burning rate is less than 70 mm per minute; or extinguished in 100 mm signs before.V-2: the flame was extinguished in 60 seconds after the two and 10 second combustion test of the sample. A fire can fall off.V-1: the flame was extinguished in 60 seconds after the two and 10 second combustion test of the sample. No fire can fall.V-0: the flame was extinguished in 30 seconds after the two and 10 second combustion test of the sample. No fire can fall.
UL is a plastic material standard test piece by spontaneous combustion flame after the combustion time, combustion speed, falling particle state to set the plastic material fire resistance rating, according to the level of quality, followed by HB, V2, V1, V0, 5V, VTM-0, VTM-1 and thin material grade, VTM-2, and foam material grade HBF, HF-1, HF-2.
