The maintenance department recently has received complaints about inadequate lighting from various managers, the HR department, and production employees. You reviewed the lighting layout drawings and lighting specifications and have found that, if anything, the areas in question are slightly over-lit. You know that low voltage can cause significant lumen output reduction, but you checked the system voltage and it’s where it should be. What should you do to investigate and resolve the cause of the complaints?

Begin with a formal lighting survey conducted by a qualified lighting expert. This includes walking down the areas under complaint and recording the lumens at points where people are working.

If the lumens are adequate, the problem may be the type of lighting rather than the amount of light. Ask the lighting expert to examine things from that angle next. You may solve the problem with task lighting, or you may need to replace existing lamps and fixtures to get the correct color rendition and other lighting characteristics.

If the lumens are inadequate, pick any fixture at random and thoroughly examine it. Things to check include:

  • Lens. Compare it to an unused lens (new or spare), to see if it's scratched, dirty, or compromised in any way that reduces light output.
  • Shade. Do you need to adjust (e.g., raise) the shade for more output?
  • Neutral. If you have high harmonic content, your neutral may be insufficient. Put a power analyzer on the branch circuit to see what you're dealing with.
  • Ballast. If the previous three steps are satisfactory but light output is still low, redo the connections to the ballast leads or try replacing the ballast with a new one.
  • Location. The light itself may be fine, but reconfiguration on the plant floor means it's in the wrong place. Move the fixture.