Flammability UL 94 HBF

Horizontal Burning Foamed Material

The horizontal burning test on foamed materials is used to determine the UL 94-HBF, HF-1 and HF-2 flammability ratings taking account of the calculated density.

Vorbehandlung:
2 days / 23 °C / 50 % relative humidity.
7 days / 70 °C / hot air oven

Flame height 38 mm
Flame application time 60 s

 

Flammability rating UL 94 HBF
Test criteria (test specimens) HF-1 HF-2
Burning time (s) 4/5 ≤ 2
1/5 ≤ 10
4/5 ≤ 2
1/5 ≤ 10
Burning and afterglow times of each individual specimen (s) ≤ 30 ≤ 30
Dripping of burning specimens
(ignition of cotton batting)
no yes
Damaged length of each individual specimen (mm) < 60 < 60
Criteria for HBF ratings
  • Burning rate ≤ 40mm over a distance of 100 mm
  • Flame or glow is extinguished before 125 mm mark