First, according to the classification method of building materials combustion performance (GB8624-1997), polyurethane meets the requirements of B2 level, adding special flame retardants can reach B1 level. Some indicators have reached a Class A
Two, GB8624-1997 index
Noncombustible materials (a)
1, a grade homogeneous material
The combustion performance should be reached according to the GB/T5464 test.
A) the average temperature rise in the furnace is not more than 50 degrees C.
B) the average continuous combustion time of the sample is not more than 20s.
C) the average mass loss rate of the sample is not more than 50%.
2, a class composite (sandwich) material
To meet the requirements of the following materials, the combustion performance is determined to be A.
A) were tested by GB / T 8625, the average length of each trial remaining pieces of more than 35 cm (either try remaining length >20cm pieces), and each time the average temperature of flue gas is less than or equal to 125 DEG C peak test, specimen back without any burning phenomenon;
B) were tested by GB / T 8627, the smoke density rating (SDR = 15);
C) testing according to GB / T and 14402 GB / T 14403. The material calorific value is less than or equal to 4.2 MJ / kg, and the unit area of the test piece heat release is less than 16.8MJ / m^2;
D) combustion of materials not lethal concentration of LCo = 25mg / L smoke toxicity.
Combustible materials (B grade)
1, Bl grade material
To meet the requirements of the following materials, the combustion performance is determined to be B1.
A) test according to GB / T 8626, its combustion performance should reach the index of GB / T 8626 and do not allow combustion drip to ignite the filter paper.
B) were tested by GB / T 8625, the average length of each trial remaining more than 15cm pieces (either try remaining length >0cm pieces), and each time the average temperature of flue gas is less than or equal to 200 DEG C peak test;
C) were tested by GB / T 8627, the smoke density rating (SDR = 75).
2, B2 grade material
The GB / T 8626 is used to test the filter paper. The combustion performance should reach the target of GB/T 8626, and the phenomenon that there is no burning drip to ignite the filter paper is not allowed.
Three. Other standards
In 1 and 1997, the national standard "classification method for the combustion performance of building materials" GB8624-1997, its B1 grade PU material index, oxygen index must be more than 32;
2, 2006 issued by the national standard "code for fire protection design of buildings" GB50016-2006, the PU composite wind pipe material is less than 25 SDR smoke density index.