The type of lighting selected for a sports application will depend upon the activity requirements. In Switzerland, these are usually
defined in norm EN 12193 unless a higher level is stipulated. The parameters can be calculated at the design stage with suitable inputs
to a professional simulation program such as Dialux.
Lighting Selection Parameters
The primary requirement will be to achieve an average lux level over the whole playing area (vertical lux measured at 1m), together with
an appropriate level of light distribution (minimum lux/average lux). Further considerations are: - glare ratio (GR) for players and for
outdoor sports lighting designs; upward light ratio (ULR - a measure of atmospheric pollution), overspill light (vertical lux) and
luminaire intensity (LI) for neighbours, are becoming increasingly important, according to the classification of the surrounding area.
Glare is a phenomenon experienced when an observer is subjected to an intensity
of light that is significantly brighter than the average level (headlights of
oncoming traffic can be glaring at night but not during the day)
Use of large area product (to reduce source intensity) or multiple small light
sources helps to minimise glare, positioning of the light sources away from
players sight line should also be considered.
Upward Light Ratio (ULR)
Upward light ratio is the proportion of light from a system (direct and reflected)
that is emitted above the horizontal axis.
Overspill light is simply unwanted light outside of the target area such as on a
Luminaire Intensity (LI)
Luminaire Intensity is direct glare for observers outside the illuminated area; it
is a function of the source intensity and the angle from which it is viewed.