Exitance Coefficients

The ability to predict the surface exitances in the visual environment is useful in order to design lighting that promotes both visual comfort and good visual performance. Exitance coefficients, like coefficients of utilization, may be computed for any specific luminaire and substituted into a variation of the lumen method formula in place of the coefficient of utilization. The result obtained is either the average wall exitance of the average ceiling cavity exitance, rather than illuminance on the workplane.