Lumen Effectiveness Multipliers For Outdoor Lighting Design

Perhaps one of the most fascinating and important subjects to be addressed in our industry over recent years is the effect of lamp spectral distribution on visibility. In the past, it has been widely accepted that under virtually all circumstances where artificial light is used, lighting level calculations could ignore spectral effects. In IESNA and CIE practice, recommended lighting levels do not consider light source color. When calculating such levels in practical design situations, results are based on a certain lamp lumen rating, usually as provided by the manufacturer. Calculated values of candelas, lux or candelas per sq.m. are not dependent upon whether the light source is bluish white, pink or yellow.