TESTING THE RELEASE OF TOXIC DEGRADATION PRODUCTS OF COMBUSTING MATERIALS WITH A METHOD ACCORDING TO POLISH STANDARD PN-B-02855
The principle of the method consists in the quantitative determination of the products of thermal decomposition and combustion of materials decisive for the toxicity of the fire environment. The thermal decomposition and combustion of samples of the test material shall be carried out in a movable horizontal tube furnace (Fig 1) at temperatures of 450 oC, 550 oC and 750 oC. At the time of the test, the specific mass emissions of CO2, HCN, NO, NO2, SO2 and HCl shall be determined, which means the mass of the toxic product produced during the thermal decomposition and combustion of the material mass unit in the test conditions concerned.
Stand for testing the release of toxic degradation products of combusting materials with a method according to PN-B-02855
The FTIR analyser is used to measure the specific mass emission, which measures continuously the mass concentration – cmi of the CO, CO2, HCN, NO, NO2, SO2 and HCl in the flowing products of the thermal decomposition and the combustion of the material sample. On this basis, for the specific weight of the mp sample and the volume flow rate of the gases. The control-measuring system of the position shall determine the mass emission Ei for each of the measured gases.
On this basis, for the mass of sample and the volume flow rate of the gases, the control-measuring system shall determine the mass emission Ei for each of the measured gases. On the basis their average values are defined toxicity index - WLC50SM, which is the mean value of the toxicity indexes defined at temperatures 450oC, 550oC and 750oC. In depending on the value WLC50SM he thermal decomposition and combustion products of the test material are classified as follows:
WLC50SM ≤ 15
decomposition and combustion products very toxic
15 < WLC50SM ≤ 40
decomposition and incineration products toxic
WLC50SM > 40
degradation and combustion products are moderately toxic
The FTIR Analyzer is located in the adjacent room. This reduces the impact of air pollutants in the test zone the result of a spectrum analysis.
The test at each temperature must be prepared after 3 samples. The mass of the sample should be 4+/-0.1g and should be evenly distributed over the length of the cuvette. Has The maximum thickness of the sample should be 5mm. For materials with an apparent density less than 0.1g/cm3 a solid sample is allowed to a thickness of 10mm. Samples must be prepared by the appropriate processing method for the material or by cutting of the finished product with the layers representativeness.
Applying research methods – in Polish civil engineering for toxicity studies of furniture thermal decomposition and combustion products.