NALMCO Certified Apprentice Lighting Technician (CALT) Practice Exam

Which of the following can result from dirty luminaires?

1. Increased energy consumption

2. Improved light diffusion

3. Enhanced aesthetic appeal

4. Decreased light output

The correct answer is: Decreased light output

Dirty luminaires can significantly impact lighting performance, primarily by decreasing light output. When luminaires are coated with dust, dirt, or other contaminants, their ability to effectively transmit light is compromised. The presence of these obstructions scatters and absorbs light, leading to a reduction in the overall illumination provided in a space. This decrease in light output may necessitate the use of additional lighting or higher wattage bulbs to achieve the desired brightness, ultimately affecting energy efficiency and lighting quality. While other options can be considered, they do not align with the reality of what happens when luminaires are not clean. Increased energy consumption can occur as a necessity to compensate for decreased light output, but it is not a direct result of dirty luminaires alone. Improved light diffusion and enhanced aesthetic appeal would typically require clean equipment; thus, these outcomes are unrelated to the condition of the luminaires being dirty.