Test specimens used are of a constant mass dried at 40°C.
The rate of weight change after drying a specimen stored in a normal state at 40ºC. Weight after drying is the baseline weight.
300mm × 400mm sample specimen set on a support table measuring 350mm. At wet state, the sample specimen is left standing for 96 hours under control conditions of a temperature of 40ºC and humidity at 85~90%rh.
When a 500g steel ball is dropped onto a 300mm × 400mm sample specimen, placed on sand, it shall not form cracks and an indentation formed shall be smaller than the predetermined diameter. The height from which the steel ball is dropped diﬀers depending on the thickness of sample specimen.
Height of Drop
When both sides of a 50mm × 300mm sample specimen with a weight of 1000g are exposed to two gas burners at 1000ºC for one of the predetermined durations listed below, the sample specimen shall not break nor drop. Exposure time differs depending on the thickness of sample specimen.
・Thickness of 12.5mm (8 minutes exposure)
・Thickness of 15.0mm (10 minutes exposure)
・Thickness of 21.0mm (12 minutes exposure)
A sample specimen soaked in water for 2 hours is checked to see whether its paper facing peels off from the core. Specimens that have been measured for water absorption content are used.
The rate of weight change when a 300mm × 300mm sample specimen is soaked in water for 2 hours. Weight before soaking in water is the baseline weight.
The rate of weight change when a glass tube with an inside diameter of 60mm is placed on the board with the tube periphery sealed, in which water is poured to a height of 50mm and left standing for 3 hours. Weight before water absorption is the baseline weight.
After 48 hours irradiation with a UV carbon fade meter, the specimen shall not show discoloration that exceeds level 3 of the gray scale for discoloration-fade and there shall be no cracks, swelling, or wrinkles on the surface.
Speciﬁcation showing non-ﬂammability. The rise in temperature and the degree of smoke emission are checked during heating. JIS A 1321 testing method.
Value indicating how dificult heat transmission is. JIS A1420 or JIS A1412-2 testing method.
Speciﬁcation showing non-ﬂammability. Based on the Building Standard Law.
Maximum load when a 50mm × 50mm sample specimen is compressed towards the thickness direction.
Maximum load to sink the head of a nail that is already nailed into the board.
The rate of size change of a 40mm × 100mm sample specimen, which is dried at 40ºC, and then left standing in open air for a day at 23ºC and 90%rh humidity.
Value showing the ﬂexural rigidity of the board. Calculated from the ﬂexural fracture load measurement data.
Measurement of the mass of a 100mm × 100mm sample specimen sealed with aluminum tape, except for the face side, which is maintained in a predetermined condition. Mass 1: 23±0.5°C 53±3%RH Constant mass Mass 2: 23±0.5°C 93±3%RH 24 hours Mass 3: 23±0.5°C 53±3%RH 24 hours Moisture absorption (g/m2) = (Mass ②－ Mass ①)/ Sample specimen one surface area Moisture desorption (g/m2) = (Mass ②－ Mass ③ )/ Sample specimen one surface area.
The strength required to fracture a 150mm × 75mm sample specimen when a round steel bar (φ 2.6mm) is inserted into a point 12mm away from the edge of the specimen, and then tensile load is added.