When considering an efficient lighting retrofit, it’s prudent to consider not just luminaire efficiency, but also the overall lighting design in your facility. IES (Illuminating Engineering Society) recommended practices address minimal footcandle requirements for specific space types, while also considering uniformity, background contrast, surface brightness (glare) and weighting factors such as age of occupants and speed and accuracy of tasks.

Two important questions to ask:

  1. Is the facility currently under or over illuminated for its space function?
  2. Are tasks adequately illuminated for quality and safety?

Many older designs were intentionally slightly over-lit to allow for the rapid degradation of the source (metal halide, for example), and simply replacing one-for-one with similar output-rated LED product (which has little degradation by comparison) could result in much higher illumination levels and wasted energy.