How to get maintenance factors right in an LED world

Despite the switch to LED from traditional lighting sources, many specifiers are still using 0.8 as the maintenance factor for their installations. But with LEDs, everything has changed, and an MF of 0.8 is not suitable for all projects. Lamp lumen maintenance and luminaire maintenance are completely different in a solid-state world, and care must be taken to avoid over- or under-specifying light levels, with consequent implications for energy usage and the lit environment over the installation’s lifetime.


Learning points

  • Why 0.8 is no longer a useful rule of thumb
  • How to work out the service life of LED sources
  • Where to find accurate information
  • How to accurately calculate the MF for an LED installation



  • Lighting manufacturers
  • Consulting engineers
  • Lighting designers