Abstract:

The burning behaviour of the plantation wood (two softwoods and one hardwood) treated with ammonium phosphate (NH₄H₂PO₄) was tested by cone calorimeter in the study. The sample with size of 100 mm by 100 mm (LT or LR section) by 10 mm (thickness) was prepared for fire retardant treatment and cone calorimeter test. The heated area was on LT or LR section, heat flux was 50 kW·m^-2. The results showed that the ignition time of the treated wood depended on the amount of the fire retardant and the treated wood could not be ignited when the amount of fire retardant was higher than 100 kg·m^-3. The fire retardant was efficient in reduction in the heat release and mass loss and the efficiency in reduction in the heat release was increased with the amount of the fire retardant increased. But the fire retardant was unsatisfactory in retarding smoking. The smoke of the treated wood appears on the whole process of heating, and the strongest and stronger process of smoke production was reduced. However, the weakest process of smoke production became stronger and it was increased with the amount of the fire retardant increase. The distribution of the fire retardant in wood structure was important and it could affect the burning behaviour as a material.

Key words: burning behaviour, fire retardancy, plantation wood, cone calorimeter