Optical Characteristics Impact Factor Assessment for Emergency Lights

Abstract

This study conducted candlepower distribution tests to analyze the characteristics of emergency lighting. The spatial luminous intensity distribution of light intensity lamps was obtained. The experimental results for groups of samples were compared, including lighting structure, light specifications, installation, and input voltage as well as other factors affecting the optical characteristics of the lights. This study found that the impact on the surface level of illumination using different mounting directions varies greatly, with top inlay models performing better than wall-mounted lighting fixtures. A wall-mounted luminaire mounting height of 2.5 m did not meet the standards of the ground-level 21× luminance values specified earlier. In addition, the study found significant differences between the emergency light’s stated power consumption and its actual power consumption at nominal power; however, the stated nominal power consumption of most commercially available emergency lighting is less than half of the actual consumption, and the total flux is only around 1/8 of the stated value. This significant gap causes the current design of emergency lighting to be a mere formality, because the lights are unable to provide the basic lighting required for emergency evacuations. This may also cause casualties during evacuations due to equipment failure.