Experimental Investigation of Pollutant—Luminous Environment Relation Under Tunnel Fire Condition Based on Spectral Analysis

The mature theory of safety assessment and system operation is crucial to ensure the safety and property of commuters under the tunnel fire condition, but the relationship between pollutants and the quality of the luminous environment is still the weakest link in this research area. To establish this close relation, this study adopted three different scaled experiments to investigate the pollutant-visibility model based on spectral analysis. The first scaled tunnel model fire experiment, conducted on a 20.5-m-long experimental platform, utilized three combustion sources to analyze the light attenuation of natural gas, PVC-insulated cables, and smoke cakes based on the APE index. Then the spectrum selective contrast experiment collected several typical spectral data from coloured transparent panels, and the compared results advocated that there is no much different impact on luminous environment with these combustion sources under smoky conditions. At last, the acrylic box pollutant experiment was conducted with different CO/NO2 concentrations, and the results provided quantitative relationship between the light average attenuation rate and CO/NO2 concentrations. The findings of this study could be able to further establish the connection between pollutants and safety evacuation, as well as ventilation and luminous environment by combining the relatively mature research of tunnel fire.