Comparison of plastics flammability rating

A total of 12 kinds of UL94: HB, V-0, V-1, V-2, 5VA, 5VB, VTM-0, VTM-1, VTM-2, HBF, HF-1, HF-2.
UL94 flammability grade is the fluorescent brightener  most widely used plastic material flammability standards. It is used to evaluate the material's ability to be extinguished after ignition. According to combustion speed, combustion
Time, anti-drop capabilities, and can have a variety Bubble whether combustion evaluation method. Each test material according to the color or thickness can get a lot of value. When selecting a product
Material, its UL rating should meet some plastic parts wall thickness requirements. UL rating should be reported together with the thickness value, and not only the thickness of the UL rating report is
Enough.
Plastic flammability rating by the HB, V-2, V-1, V-0, 5VB to 5VA of incremental:
HB: UL94 standard lowest level of flame retardant. Requirements For 3-13 mm thick sample, the combustion speed is less than 40 mm per minute; less than 3 mm thick sample,
Burning speed is less than 70 mm per minute; or signs to 100 millimeters off.
V-2: the sample twice 10 seconds combustion test, Yu & Yu burning flame extinguished in 60 seconds. Drip particles can ignite cotton.
V-1: the two samples after 10 seconds burning test, Yu & Yu burning flame extinguished in 60 seconds. Dripping particles can not ignite cotton.
V-0: the two samples after 10 seconds burning test, Yu & Yu burning flame extinguished in 30 seconds. Dripping particles can not ignite cotton.
5VB: five times for 5 seconds the  PVC stabilizer for pipe sample combustion test, Yu & Yu burning flame extinguished in 60 seconds. Dripping particles can not ignite cotton. For the bulk sample is allowed to be burn.
5VA: five times for 5 seconds the sample combustion test, Yu & Yu burning flame extinguished in 30 seconds. Dripping particles can not ignite cotton. For the bulk sample does not allow burned
Wear.
The wire UL1581 combustion:
1, VW-1: vertical burning test (UL wire flame rating)
2, FT1: vertical flame test;
3, FT2: horizontal flame test;
4, FT4: vertical flame test;
5, FT6: horizontal flame and smoke tests. (FT class combustion level is CSA standard wire flame rating)
These levels:. VW-1 and FT1 same grade. FT2 most easily passed, the lowest level. (FT6> FT4> FT1> FT2);
VW-1 strictly in FT1, both of which are vertical burning criteria: 1. Burn marks (kraft) more than 25% can not be carbonized; 2.5 times of 15 seconds burning continued
Burning time can not be more than 60 seconds; 3. Flaming droplets can ignite cotton; VW-1 requirements to meet 1,2,3; FT1 only required to meet the 1,2
For wire industry:
To UL 94 V-2, V-1, V-0, 5VA, 5VB assessment is wire the materials used, the test with the test material to another sample of the development of standards, not on the wire identification.
VW-1 VW -2 FT-1 FT-2 appraisal from the  Acrylic impact modifier cable itself, the test is passed, you can identify the corresponding level on the wire.
Wire with UL94 flame retardant are two entirely different things, an analogy of an insulating material through UL94 V-0, but not necessarily be able to pass VW-1;
Another insulating material is flame retardant UL94, and wire flame retardant requirements generally in UL758 62 1581 on; different objects;
Therefore, V-0 V-1 UL94, etc. are not the inside of the flame retardant electric wire; the AWM wire is not printed on the "V-0"!
VW-1/FT1 with UL94 V0 flammability test of the device there is a big difference:
1, the flame height and temperature of the type
2, the test traffic is used for different methane
3, back pressure is different methane
4, the combustion chamber volume is also different: VW-1 requires more than 4 cubic meters, while more than 0.5 cubic V0 can only require
5, the combustion is also different times
6, the combustion results: V0 Records residue burning time, and VW-1 then do not!
But UL94 5V level in combustion and combustion VW-1 test conditions and test methods almost close!