NALMCO Certified Apprentice Lighting Technician (CALT) Practice Exam

What factor decreases a luminaire's light output?

1. Dirt buildup in the luminaire

2. Scheduled periodic cleaning

3. Replacing the lamps

4. Closing the blinds on the windows

The correct answer is: Dirt buildup in the luminaire

The correct answer focuses on how dirt buildup in a luminaire negatively impacts its ability to effectively emit light. Over time, dust, grime, and other contaminants can accumulate on the surface of luminaire fixtures, lamps, and lenses. This buildup obstructs the light that is supposed to pass through and can result in diminished brightness and uneven light distribution. Therefore, maintaining cleanliness is crucial for optimal light output, as dirty luminaires can significantly reduce the efficiency and intensity of the light produced. The other choices highlight actions that either maintain or improve light output: scheduled periodic cleaning removes debris, replacing lamps ensures that worn-out or inefficient bulbs are updated, and closing blinds may be used to control light levels but does not diminish the output of a luminaire itself.