UL94 There 12 levels:
HBM, V-0, V-1, V-2, 5VA, VTM-0, VTM-1, VTM-2
HBF, HF1, HF2 for foam materials
Level test program is as follows:
1) HB: Horizontal Burning Test
2) V0-V2: Vertical Burning Test
3) 5VA / 5VB: 5V 500w (125 mm) Vertical Burning Test
Use application:
– This standard applies to equipment and electrical parts of the plastic flammability test
– The final acceptance of the material depends on its use in the overall plant and in accordance with the standards applicable to the equipment
– This standard can be used for other non-metallic materials; but does not apply to building materials and decorative plastic materials
– The methods described in this standard include standard size samples and are only used to measure and characterize the flammability of materials used in equipment and electrical appliances relative to heat and flame in controlled laboratory environments
Qualified Analyze:
UL94 HB: Horizontal combustion
The plastic burns slowly but does not extinguish itself. This type is the lowest level of UL, often with vertical V0, V1 or V2 approach does not work when using this method.
UL94 V0, V1, V2, 5V: vertical combustion
UL94 V0 Method of assessment: After the flame has been removed after ignition, the sample can be self-extinguished rapidly to within 10 seconds of no burning of the melt (ie, the burning of the melt is located one foot below the test sample Cotton pad, can not ignite cotton).
UL94 V1 evaluation method and V0 similar, but it requires a longer self-extinguishing time. This test allowed the melt to drip onto the cotton pad, but not the cotton.
The UL94 V2 is the same as the V1 except that it allows the burning droplets to ignite cotton below one foot.
UL94 5V is the most stringent detection method, it relates to the actual plastic products in the flame life. The test required a flame length of 5 in. Five burns were applied to the test specimen. No droplet dripping was allowed during the test. The test sample was not allowed to distort significantly and no burnt holes could be produced.
