NALMCO Certified Apprentice Lighting Technician (CALT) Practice Exam

The presence of a buzzing noise, flickering, or humming sounds in a fluorescent fixture is a strong indicator of issues within the lighting system. These symptoms often point to problems such as a faulty ballast, defective bulbs, or loose connections. Flickering can occur when the lamp is not receiving a steady supply of power, which may be caused by aging components or electrical interference. A buzzing or humming sound is frequently a sign that the ballast is malfunctioning, as it may not be able to properly regulate the current flowing to the fluorescent lamps. Identifying these auditory and visual indicators is crucial for troubleshooting and maintaining the efficiency and safety of lighting fixtures.

In contrast, consistent brightness, stable temperature, and clear illumination generally characterize a functioning and well-maintained fluorescent fixture, suggesting that there are no underlying problems that need to be addressed.