ITF TENNIS GUIDE
Lighting
ITF guide to lighting tennis courts
1. Introduction
Lighting is required for indoor tennis courts and outside courts when no natural light is available. It is important because it:
- extends the playing time of a court;
- attracts more coaches and players; and
- achieves an increase in revenue from court hiring fees.
When lighting a tennis court, the objective is to ensure good visibility enabling both participants and spectators to follow the progress of a game. The ball, regardless of its location and speed, should always be clearly visible. Creating good visibility requires sufficient contrast to be created between objects and their backgrounds, good illumination levels and even distribution of light across the playing surface (uniformity).
It is important to note that lighting design and installation requires specialist engineering knowledge and must be carried out by competent experienced professionals following the guidelines required by government or any other relevant authorities
It is also important to note that this guide is not intended to provide lighting recommendations and solutions in case of television coverage for which specialist knowledge is required.
2. General considerations
When planning a lighting installation, the following general design issues should be considered:
- The intended standard of play – this will govern the dimensions of the courts, the level of illumination, uniformity, etc.
- Relevant government requirements and permissions in force locally.
- Installation and running costs, including maintenance, heating or cooling and light source replacement.
- Access to and the cost of a suitable power supply.
- General everyday maintenance including cleaning and repair lighting units.
- The effects on others of spill light.
3. Key terms
Horizontal Illuminance
This is the amount of light falling on the court surface; it is often referred as lighting level. It is expressed in lux (or foot-candles in the USA).
Eh average is the average value of the horizontal illuminance calculated/measured on the reference grid.
Uniformity of illuminance
This is a parameter describing how evenly light is distributed over the court surface.
Emin/Eh ave. is the minimum value of the horizontal illuminance calculated/measured on the reference grid divided by the average value.
Glare
This is the disturbing effect which impairs the vision; it depends mainly on the ratio between the direct brightness of a lighting installation and the brightness of the court surface.
GR is the Glare Rating factor assessing the quality of the installation from a glare perspective
Colour temperature
This is the apparent colour of a light source; it is expressed in Kelvin (K).
Colour rendering
Colour rendering describes the ability of a light source to reveal and reproduce colours accurately.
It is ranked by the colour rendering index Ra (from 0 to 100) where the higher the index the better the colour accuracy
Obtrusive light
Spill light, which because of quantitative, directional or spectral attributes in a given context gives rise to annoyance, discomfort, distraction or reduction in the ability to see essential information.
In the case of outdoor sports lighting installation obtrusive light is considered around the installation and not for spectators, referees or players within the sports area.
4. Lighting standards
Some National Associations and governments have set different requirements for indoor or outdoor lighting and may use different units of measurement. However, as a guide, the following shows the minimum standards according to the European Standard for Sports Lighting, EN 12193:2008 where:
- Class I: Top-level national and international competitions (non-televised) with requirements for spectators with potentially long viewing distances.
- Class II: Mid-level competition, such as regional or local club tournaments. This generally involves medium-sized numbers of spectators with average viewing distances. High-level training may also be included in this class.
- Class III: Low-level competition, such as local or small club tournaments. This does not usually involve spectators. General training, school sports and recreational activities also fall into this class.
Lighting requirements for ATP, WTA and Davis Cup World Group and Zonal Group I competition are available here.
5. Lighting recommendations
5.1 General recommendations
Reference area
The Total Playing Area (TPA), for which the following lighting requirements are defined, includes the Principal Playing Area (PPA) and extends to a perimeter of 1 m inside the perimeter of the court.
Reference grid for calculation and measurements
Calculations and measurements of the performance of a lighting installation should be done on a specific grid, where grid points are determined by the length and width of the TPA.
For horizontal illuminance the reference level of the grid is the ground.
For calculation, it is recommended to define a grid of 15 points along the length direction and seven points along the width direction of the TPA, with a grid spacing of 2.5 × 2.5 m. Measurements can be done by using only one point out of two, on 5.0 × 5.0 m spacing (see figure 1 in Appendix).
Maintained values
The lighting level provided by an installation will decrease throughout its life, mainly as a result of depreciation of lamps and luminaires (see also section 7 below).
Average illuminances given in table.5.2 and table 5.3 are maintained values under which the lighting level should never fall below, during the whole operation of an installation.
Usually a maintenance factor is specified to compensate for ageing and soiling of the light sources, reflectors and front glasses. In the absence of relevant information, it is recommended to use a maintenance factor of 0.8.
Spectator area lighting
For the visual comfort of spectators rather than safety or emergency reasons, the lighting level should be at least 10 lux.
5.2 Lighting recommendations for outdoor courts
5.2.1 Lighting requirements
The following table is a summary of the criteria for outdoor courts:
*The above average Horizontal illuminances are maintained values.
5.2.2 Installation recommendations
In order to get the appropriate horizontal illuminance on the ground (average level and uniformity) and also a sufficient illuminance level to reveal the ball in flight within the playing volume above the court, while ensuring that players do not suffer from disability glare, positioning and height of luminaires should be carefully considered as well as the choice of luminaire.
It is recommended to use sharp cut off luminaires, with accurate light output control, mounted on columns; for a single court, mounting height between 8 and 12 m is generally appropriate to achieve the above conditions.
Columns are set up on either side of the TPA, using two to four column positions on both of the longitudinal sides, depending on the required quality of the lighting system (see figure 2 in Appendix).
Two or three adjacent courts can also be lit without installing columns between the courts, for which the mounting height has to be increased ‘proportionally’. Where appropriate, adjoining courts can share the same columns to support the light fittings.
Columns should be positioned so that participants are unlikely to collide with them.
As a rule, the mounting height has to be defined in relation to the lighting requirements and the column locations.
Note: As underground wiring is recommended for lighting columns, it may be necessary to incorporate the containment for the wiring system during the construction of the tennis court, particularly if columns are required between courts located near the net posts.
5.2.3 Spill light
The potential impact on the environment of light spill from outdoor lighting installations should be considered during design of installations.
In countries where light nuisance is not a recognised statutory nuisance, recommended values for the control of obtrusive light for various environmental zones with respect to:
- Limitation of illumination on surrounding properties.
- Limitation of bright luminaires in the field of view (luminaire intensity).
- Limitation of sky glow (upward light).
- Limitation of the effects on road users (TI).
given in the European Standard for Sports Lighting, EN 12193:2008, can be applied.
Ev is the maximum value of vertical illuminance on properties.
I is the light intensity of each source in the potentially obtrusive direction.
ULR is the proportion of the flux of the luminaire(s) that is emitted above the horizontal when the luminaire(s) is (are) installed.
Note: Lower values may apply in relation with Light on properties and Luminaire intensity where curfews are implemented.
Limitation of effect on road users - Maximum values of threshold increment (EN 12193)
TI calculation as given in EN 13201-3.
5.3 Lighting recommendations for indoor courts
5.3.1 Lighting requirements
The following table is a summary of the criteria to achieve quality lighting for indoor courts:
*The above average Horizontal illuminances are maintained values.
5.3.2 Installation
Recommended systems of lighting use luminaires that are mounted parallel to the sidelines and outside the PPA.
No luminaires should be positioned in the part of the ceiling which is directly above the area limited by the rectangle of the marked area extended to the full depth of the run back behind the base lines.
The interior surfaces of indoor courts can help to make the ball more visible against them however, the right choice of colour and reflectance can also assist with perceived quality of the lighting installation. Background colours of blue or green are preferable and should be as uniform as possible.
Glare from windows – positioning windows at low level alongside the court and not behind the server reduces this possibility.
6. Light sources
Many types and lamps available today can be used for the lighting tennis courts. The most appropriate lamps in common usage are described below, including the range of lamp types and wattages and efficacies. Efficacy describes the ratio between the light output (lumens) and power input (watts).
7. Maintenance and cost of ownership
A new lighting system represents a considerable investment. Once this investment has been made the system should be maintained to ensure its performance over many years.
As well as the installation costs (equipment and labour), a lighting system will have ongoing variable costs that it will attract over a number of years. This reviewed as part of the design, elements of such an analysis include:
- Initial system cost excluding lamps.
- Cost of lamps.
- Estimated operational hours per year.
- Load of system in kW (including gear losses).
- Electricity cost per kW/ hour.
- Number of lamp replacements over the assessment period.
The light emitted by lamps depreciates over time as the components wear. However it is very important to note that efficiency is also reduced by dirt. Regular maintenance of lamps and fittings includes cleaning and is necessary to ensure that the installation continues to meet the original design specifications as efficiently and economically as possible.
Maintenance comprises cleaning, safety testing, the regular replacement of lamps and other components with a limited service life, as well as the timely replacement of worn or damaged parts. Maintenance contributes to efficient energy consumption and prevents unnecessary costs. It should be carried out at least once a year or at the latest when the average illuminance has fallen to the average specified minimum illuminance.
Lamps can be replaced individually or all the lamps in an installation can be replaced at the same time. Apart from lamps that fail at an early stage it is best to replace all the lamps at the same time. This prevents large differences in light characteristics between old and new lamps. Individual lamp replacement will be necessary if the contribution of the light source in question is indispensable such as in outdoor installations with a small number of lamps or for emergency and safety lighting.
Appendix
Figure 1. Reference grid for measuring light levels.
Figure 2. Typical mast layout for outdoor courts.