Lighting for education
Correct lighting is important in all areas of life, but if we were to quantify which activities require the highest quality of light, then lighting for education would be fairly near the top of that list.
Why should we consider lighting for education so important? Well, lighting impacts on the ability of our children to learn and be stimulated, it also affects the feeling of wellbeing within the learning environment. It is well documented that poor lighting can lead to behavioural problems, and can affect the minds ability to concentrate, as well as the obvious problems of eyestrain, headaches and fatigue.
Of course any lighting system has to be sustainable and energy efficient, it is no good giving our future generations what we consider perfect lighting to learn in, if we are at the same time jeopardising the sustainability of the environment they will be living in when they grow up.
There is guidance available for lighting in schools and the educational environment, although it is not always easy to find, and often information from other interior lighting guides needs to be adapted. One publication which gives some good guidance is Building Bulletin 90 by the DfEE, which makes mention of direct/indirect lighting, task lighting and making use of natural light. The European standard EN12464-1:2002 quantifies the light levels to be achieved in various areas within the educational environment and the SLL code for lighting gives further guidance on achieving a well lit interior.
Although there is a lot more to lighting design than just meeting the recommended light levels for various activities, the use of up to date lighting software can go a long way to helping to achieve not only the desired light levels on the working plane but also the desired ambience and effects on other room surfaces. The introduction of projection equipment and smart boards has added new challenges to the lighting design, and the new Part L has increased the pressure to come up with more energy efficient solutions and encouraged the use of lighting controls.
The latest generation of high efficiency fluorescent lamps (T5 HE lamps) along with the use of well designed luminaries has meant that energy usage can be cut dramatically which has a knock on effect reducing heat input into the class area, which is important in ICT rooms. A twin 35W louvred T5 fitting can be used where an older style 2x58W prismatic luminaire was normally installed giving at least 40% energy savings.
Lighting controls can be added to give further energy savings. A few years ago the only lighting control you would be likely to find in the class room would be the on/off switch by the door, but with the increased use of daylight in many schools and the introduction of automatic controls which detect when the room is occupied and how much natural light is available, then the energy use can be cut even further, making the overall energy use for lighting in the building a fraction of what was possible say 10 years ago.
One thing that needs to be avoided is the use of any tungsten lamps; I have seen many schools where areas have been refurbished with energy saving lighting in classrooms and libraries, only to find 10 or 12, 150W PAR 38 tungsten spotlights in the reception area using as much energy as two or three classrooms.
Following is a break down of the main areas within a school or college with a brief note on the things to consider from a lighting point of view.
It would be foolish for anyone to say they had the perfect classroom luminaire, or lighting layout, because classrooms are used for so many different activities. It is important to consider all activities that may take place in the classroom including the possibility of the room being used for evening classes. Adults require higher levels of light for similar tasks, hence a classroom which is also used for evening classes needs to be lit to 500 lux rather than 300 lux, the decision then needs to be made as to whether dimming or separate switching should be used to give the two light levels. As with any other working environment all the room surfaces need to be considered, such as display walls and as mentioned white or smart boards.
Perception of distance and good modelling properties are important for circulation areas. So wall mounted luminaries or direct/indirect luminaries are ideal. If wall mounted luminaires are used, mounting them at the facing wall at the end of a corridor or on corners facing directly into peoples eyes needs to be avoided. As in the classroom, walls are also important as these are often used for displaying artwork or notices. 100 lux is required for general corridors, with 150 lux on stairs and 200 lux in open areas.
Like other areas, sports halls are used for a variety of activities. For sports, impact resistance needs to be considered, as well as glare to players, especially where badminton and basket ball are concerned. This area should be lit to 300 lux.
A lively interesting atmosphere needs to be created here, and this is one area where uniform lighting is definitely not required. Some areas may be lit to low levels for relaxation and other areas to high levels for stimulation. Decorative luminaires with coloured filters or even colour changing can be considered, which is where luminaries utilising LED’s or coloured lamps can come into their own.
As well as being a place to get books, libraries are also used for small exhibitions and studying. Good vertical illuminance is required on the book shelves, and display walls, but glare needs to be avoided for the study areas where there is likely to be display screen equipment. 200 lux horizontal should be provided at the base of the bookshelves and 500 lux in the study areas.
Corridors and circulation areas are key areas for installing emergency lighting. A minimum of 1 lux is required on the centre line of escape routes. In stair wells there should be a minimum or 1 lux on the stair treads. In large areas such as gymnasia, halls and foyers the emergency light level should not be less than 0.5 lux in the open area.
European standards and Building Bulleting 90, say that areas less than 60m² do not necessarily require emergency lighting which would suggest that normal classrooms which are usually smaller than this do not need to be considered. However for safety reasons and considering that class rooms are often used for evening education by people unfamiliar with the building layout, emergency lighting may be considered necessary.