Flame Resistance testing
left: silicone rubber / right: organic rubber
UL 94 Flammability Rating
The UL 94 test determines the material's tendency either to extinguish or to spread the flame after ignition of the specimen. The test program is described in UL 94, The Standard for Flammability of Plastic Materials for Parts in Devices and Appliances, this is harmonized with IEC 60707, 60695-11-10 and 60695-11-20 and ISO 9772 and 9773.
A brief description of the six UL 94 classes can be found in this table.
| 5VA
Surface Burn |
Burning
stops within 60 seconds after five applications of five seconds
each of a flame (larger than that used in Vertical Burn testing)
to a test bar. Test specimens MAY NOT have a burn-through (no hole).
This is the highest (most flame retardant) UL94 rating. |
| 5VB
Surface Burn |
Burning stops within 60 seconds after five applications of five seconds each of a flame (larger than that used in Vertical Burn testing) to a test bar. Test specimens may a burn-through (a hole). |
| V-0
Vertical Burn |
Burning stops within 10 seconds after two applications of ten seconds each
of a flame to a test bar. NO flaming drips are allowed. |
| V-1
Vertical Burn |
Burning stops within 60 seconds after two applications of ten seconds each
of a flame to a test bar. NO flaming drips are allowed. |
| V-2
Vertical Burn |
Burning stops within 60 seconds after two applications of ten seconds each of a flame to a test bar. Flaming drips are allowed. |
| H-B
Horizontal Burn |
Slow
horizontal burning on a 3mm thick specimen with a burning rate is
less than 3"/min or stops burning before the 5" mark.
H-B rated materials are considered "self-extinguishing".
This is the lowest (least flame retardant) UL94 rating. |
| Cure Type | Shin-Etsu product name | Reaction type (by-product gas) | UL list item | ||
|---|---|---|---|---|---|
| Registered product name Material Dsg | Certified colour | Level Flame class (Min. Thk) | |||
| One- component room- temperature cure | KE40RTV | Condensation (oxime) | KE-40RTV | WT, GY | 94V-0 (0.75mm) |
| KE3424G | Condensation (acetone) | KE-3424G | GY | 94V-1 (2.0mm) | |
| KE3490 | Condensation (acetone) | KE-3490 | BK, GY | 94V-0 (3.0mm) 94V-1 (0.75mm) |
|
| KE3494 | Condensation (acetone) | KE-3494 | BK, GY | 94V-0 (1.5mm) 94V-1 (0.75mm) |
|
| KE4890 | Condensation (alcohol) | KE-4890 | ALL | 94V-0 (0.75mm) | |
| KE45 | Condensation (oxime) | KE-45 | ALL | 94HB (1.5mm) | |
| KE3497 | Condensation (acetone) | KE-3497T | WT | 94HB (0.75mm) | |
| Condensation (acetone) | KE-3497W | WT | 94HB (0.75mm) | ||
| One- component heat cure | KE1831 | Addition | KE-1831 | BK | 94V-0 (0.75mm) |
| Two- component room- temperature cure | KE200 | Condensation (acetone) | KE-200 | BL | 94HB (1.5mm) |
| Two- component heat cure | KE1204(A/B) KE1240(AL/BL) | Addition Addition | KE-1204-LTV | BN | 94V-0 (0.89mm) |
| KE1281(A/B) | Addition | KE-1281 | BK | 94V-1 (0.8mm) | |
| KE1800 | Addition | KE-1800 | WT | 94V-0 (3.0mm) 94V-1 (1.5mm) |
|
| KE1802 | Addition | KE-1802 | BK | 94V-0 (3.0mm) 94V-1 (0.75mm) |
|
For further information please visit Underwriters Laboratories Inc.