The fireproof performance of the flame-retardant polyethylene material for the conventional fire-resistant aluminum-plastic composite board is tested according to the B1 level of the national standard GB/T8624-1997 standard “Classification method of burning performance of building materials”.
In the production and certification process of flame-retardant polyethylene materials for curtain wall aluminum-plastic panels, the main items are oxygen index, density, flammability and flame retardancy.
Oxygen Index Definition: The minimum oxygen concentration expressed as a volume fraction in a (23 ± 2) °C oxygen-nitrogen mixed gas that is just enough to maintain the combustion of the material under the specified test conditions.
Method principle: The sample is vertically fixed in a transparent combustion tube, and the mixed flow of oxygen and nitrogen flows from bottom to top, igniting the top of the sample, and observing the subsequent combustion of the sample.
The time during which the sample is continuously burned or the length at which the sample is burned is compared with the prescribed judgment basis. Test a set of samples at different oxygen concentrations to determine the minimum oxygen concentration at which the sample is just maintained.
At this oxygen concentration, 50% of the tested samples have a combustion condition that exceeds the specified judgment. One.
(a) selecting a suitable starting oxygen concentration;
(b) installing the sample and adjusting the instrument;
(c) igniting the specimen as specified in the standard;
(d) evaluation and recording of combustion behaviour;
(e) successively selecting the oxygen concentration;
(f) Acquisition of valid data.
Calculation of results is calculated according to the prescribed method.
The definition of smoke density changes during the combustion to produce smoke, and the transmittance of the parallel beam passing through the smoke changes. The measured maximum specific optical density is the smoke density.
The expression method is used to measure the light absorption rate of the accumulated smoke. The formula is [(I0-I)/I0]*100, and the curve is drawn. The highest point of the curve is the maximum smoke density, and the area under the curve is the amount of smoke.