Flammability UL 94 HB
This method is used to determine the UL 94 HB flammability rating.
It is calculated for a test specimen as a function of the burning rate V and taking account of the material thickness.
Pre-treatment:
48 h / 23°C / 50% relative humidity
Stress table
| Flame application | 20 mm high Tirill burner flame |
| Flame application time | 30 s |
| If the flame front reaches the first mark within 30 s, flame applicationis discontinued. | |
| Test criteria | Burning rate in V | Flammability rating |
| Test specimen thickness 3-13 mm | ≤40 mm/min | HB |
| Test specimen thickness ‹ 3 mm | ≤75 mm/min | HB |
| Flame is extinguished before first mark | =0 mm/min | HB |
