Tài liệu Lighting with Artificial Light 02 docx

2 Good Lighting for Schools and Educational Establishments Learning environment and life environment 2 / 3 Lighting and human needs 4 / 5 Light for learning 6 / 7 Classrooms 8 - 13 Special-subject classrooms 14 - 19 Assembly halls and lecture theatres 20 / 21 Libraries 22 / 23 Foyers and display areas 24 / 25 Cafeterias and refectories 26 / 27 Staff rooms 28 / 29 Corridors and staircases 30 / 31 Outdoor areas and parking facilities 32 / 33 Sports halls and sports grounds 34 / 35 Refurbishment - Economy 36 Emergency lighting - Safety 37 Lighting management 38 / 39 Lamps 40 / 41 Luminaires 42 / 43 Standards 44 - 46 Literature, Acknowledgements for photographs and Order forms 47 Imprint 48 Information from Fördergemeinschaft Gutes Licht 49 Contents Learning is a life-long process. In modern knowledge society, in a world becoming increasingly com- plex and high tech, we need to be prepared to keep on acquiring new knowledge and learning new skills. From kindergarten to university, vo- cational school to adult education centre, there are a host of institutions available to help us do this. They de- liver the basic education we need, they help us build up our knowledge of mathematics and languages, sci- ences and subjects vital for our ca- reer, they teach us problem-solving skills and techniques for learning. 2 One important requirement for suc- cessful life-long learning is the right educational environment: a school which recognises talent and ability, encourages active and independent learning, makes education an enjoy- able experience and motivates both students and staff. Motivation and a sense of wellbeing, architecture and lighting, good visu- al conditions and efficient learning - these things are closely connected, as the solutions presented as exam- ples in this booklet will show. 4 5 6 3 2 G ermany has a population of more than 80 million - and 39 million of them are enrolled at some kind of school or educational es- tablishment. So 49% of the population - nearly every second person - spends time in a learning environ- ment. For a number of years, the Organization for Economic Cooperation and Develop- ment (OECD) has been studying the way we learn. At regular intervals, a quar- ter of a million schoolchil- dren in 32 countries are tested in three key areas: reading, mathematics and scientific literacy. The results of the surveys are published in PISA (Pro- gramme for International Student Assessment) studies. One of the most impor- tant things about the PISA studies is that they iden- tify successful educational models. Comparison of the various countries and their respective education systems reveals marked differences - differences which provide answers to the question: “How can we learn effectively?“ When children first start school, most of them are ready and willing to learn. How that willingness is en- couraged, stimulated and shaped into an attitude for life depends on lots of fac- tors: the learner, the teach- er, the social environment formed by parents, friends and colleagues - and the educational infrastructure in terms of human resourc- es, premises and technical facilities. The PISA studies show there is a connection between success in edu- cation and a motivating school environment. Stu- dents who identify with their educational environ- ment, who like going to school and feel at home there, enjoy learning, over- come learning difficulties more easily and do better at school. So students have to be stimulated and encour- aged. To learn well and effectively, we need to enjoy learning; it needs to be a pleasurable experi- ence. And age makes no difference. Wherever we learn - from kindergarten to university, at vocational school or adult education centre - the need for mo- tivation is of paramount importance. Innovative schools are required - schools which provide a motivating envi- ronment for active and in- dependent study, schools which promote individual talent and ability instead of just presenting a rigid one-size-fits-all curriculum for large groups. Inflexible forms of education and training need to make way for dynamic life-long learn- ing, where study and skill acquisition are seen as a permanent part of putting what has been learnt into practice. The innovative school also sees itself as part of our life environment, however, a place for both study and recreation, where people learn together but also share experiences. A school which is geared to this offers students and teachers the chance to work more flexibly together, to identify strengths and weaknesses and develop life-long learning strate- gies. The PISA studies also show that a positive learn- ing environment promotes motivation. A school with well-designed premises and well-equipped class- rooms, with computers and specialised literature, libraries and multimedia resources, boosts stu- dents‘ readiness to partici- pate actively in the learning process. So an investment in the school environment is an investment in the future of the knowledge society. Learning environment and life environment More information is available on the Internet at www.pisa.oecd.org 7 8 9 3 Education in Germany 39 million people of all ages in Germany are enrolled at schools, universities and other educational establishments. 20 million chil- dren, pupils and students attend the country‘s more than 100,000 kindergartens, schools and universi- ties. Nearly half of these educational establishments are day care centres, catering for more than five million children. The smallest group of edu- cational establishments - the coun- try‘s 355 universities - are attended by over 12.8 million students. Almost exactly as many people are in further education: 19 million Germans and foreign nationals in Germany regularly attend courses at adult education centres, upgrade their occupational qualifications at chambers of industry and com- merce or pursue courses of study at open universities. 10 11 12 Kindergardens, schools and universities day care centres 48,203 nursery and primary schools 20,695 secondary schools 12,079 vocational schools 11,372 other schools 8,667 universities 355 (figures indicate actual number of establishments) Adults in further education at state-funded adult education centres 9,392 other adult education centres 8,534 chambers of industry and commerce 596 chambers of handicrafts 278 distance-learning institutes 121 (figures indicate numbers of persons in thousands) Children, pupils and students at kindergartens and crèches 5,169 nursery and primary schools 3,600 secondary schools 6,449 vocational schools 2,773 universities 1,868 (figures indicate numbers of persons in thousands) All data taken from the basic and structural statistics (Grund- und Strukturdaten) published by the Federal Ministry for Education and Research and the school sta- tistics compiled by the German Federal Statistical Office 4 Lighting and human needs Reflections on paper Especially where glossy materials are used, poorly shielded luminaires cast disturbing reflections (Fig. 21) . Well shielded lumi- naires avoid this effect and permit all materials to be studied with ease (Fig. 20) . W e experience our environment first and foremost through our eyes. 80 percent of the sensory im- pressions we receive are visual. Too much or too lit- tle light, glare or distorted colours impact on what we perceive, distract our attention and cause visual fatigue. In all areas of life and throughout the working world, good and appro- priate lighting is a prime requirement for enabling us to see clearly, enjoy a sense of wellbeing, per- form concentrated fatigue- free work and perceive and interpret important information and our sur- roundings correctly. This calls for good, profes- sional lighting design. Below are some of the key factors that need to be considered for good light- ing design. Illuminance In daylight, the illuminance of an illuminated surface is between 10,000 lux (over- cast sky) and 100,000 lux (bright sunlight). Indoors, we need to make do with much less light. For writing and reading, it is generally enough if artificial lighting provides 500 lux illumi- nance; for drawing or other visually demanding tasks, illuminance should be at least 750 lux. For more information about illumi- nance values and the re- quirements of the relevant industrial standard, DIN EN 12464-1, see page 46. The values set out in the standard, however, are minimum requirements. Most people find a higher level of illuminance more agreeable and more moti- vating. In winter especially, when the levels of daylight entering a room are lower, more light is needed to avoid fatigue and loss of concentration. Glare Glare is one of the most disturbing side-effects of lighting. Direct glare caused by marked contrast differences between very bright and very dark sur- faces or due to unshielded lamps in our line of vision place a strain on our eyes and lead to fatigue and mistakes through loss of concentration. To avoid di- rect glare from lamps, care should be taken to select only luminaires which are suitable for workplace lighting. Direct glare limita- tion is indicated by a UGR index, which should be 19 (Fig. 13). Equally unpleasant and fatiguing for the eye are frequent switches between bright and dark room zones, e.g. between window and desktop (Fig. 15) . This can be avoided by correct positioning of desks, light- control blinds and good lighting (Fig. 14). Shadowing Where there is light, there is also shadow. To ensure that shadows do not impede our view when writing, the light should fall - for a right-handed person - from the left (Fig. 16) . If the light comes from the right, we write in the shadow of our own hand (Fig. 17) Brightness distribution When we are in a room, our gaze incessantly switches from near (desk- top) to far (walls). Where there are marked differenc- es in brightness between these two zones, our eyes face the constant need to re-adapt and thus get tired more quickly. Visual performance and sense of wellbeing diminish. Where the differences in brightness are not marked enough, however, the room makes a mo- notonous impression. It is recommended here that desktop luminance should not be less than 1/3 of the luminance in the im- mediate surroundings. For more remote parts of the room, the difference in luminance should be 1/5, max. 1/10. Glare limitation Glare is one of the most unpleasant visual prob- lems of all. Being dazzled by a general-diffuse lamp or the reflection of a win- dow on a computer screen affects our visual acuity and impedes our perform- ance. Direct and reflected glare can be largely avoided by good room and lighting design. Modelling Without light we cannot see an object at all, with- out shadow it is just a two-dimensional image. Only where light comes from the right direction and where the depth of shadow is correct can we perceive objects as 3D im- ages and gauge distances. To recognise three-dimen- sional objects, surfaces and structures, we need light and shade. More information is contained in booklet 1 of this series, “Lighting with Artificial Light“. Light and colour The way we perceive colours under artificial light depends on the colour rendering properties of the lamps. Lamps with good colour rendering properties produce natural colours (Fig. 18) , lamps with poor colour rendering properties cause colour distortion (Fig. 19). 13 14 16 18 20 5 Reflections on monitors Where luminaires are poorly shielded or wrongly positioned, visibility is impaired by disturbing re- flections on monitors and losses of contrast (Fig. 33) . This is avoided by good lighting design and good luminaires (Fig. 32) . Vertical illuminance Schools and educational establishments are com- munication-intensive places where clear iden- tification of faces and in- formation is essential. The key lighting requirement here is vertical illuminance, i.e. uniform bright illumi- nation of vertical surfaces such as blackboards or three-dimensional objects such as people‘s faces. For blackboard lighting, wallwashers are a particu- larly suitable choice be- cause they illuminate the writing surface uniformly without casting shadows or reflections (Figs. 22 and 24) . Where additional board lighting is not pro- vided, shadows are cast onto the writing surface (Figs. 23 and 25) . Direct lighting from above often causes undesirable shadowing on faces (Fig. 27) . In consultation zones, this shadowing is reduced by asymmetrical or direct/ indirect lighting (Fig. 26). Bright walls Good wall and entrance lighting helps people get their bearings in a room, makes for better contrasts and emphasises room zones. It also makes the room look a livelier, more interesting place (Fig 28). Direct/indirect lighting Luminaires with direct and indirect lighting compo- nents permit free arrange- ments of desks, reduce the risk of reflected glare and create a more agree- able lighting atmosphere (Fig. 30). 15 17 19 21 22 23 24 25 26 27 28 29 30 31 32 33 6 M any educational establishments today consist of large complexes of build- ings with lots of special classrooms, events and sports halls, cafeterias and refectories, administrative offices and conference zones. Schools, in par- ticular, meet this descrip- tion because a growing number of them now spread classes throughout the day. Every room in a school or educational establishment serves a particular pur- pose, for which there are special architectural solu- tions with special lighting requirements. Examples of systems which meet those requirements are found on the following pages of this booklet. For any room in a new or refurbished building, the aim should be to find the best way of harnessing natural daylight and the requisite artificial lighting. Here, however, the impor- tance of artificial lighting is often underestimated, although it plays a major role in most classrooms. In winter especially, the available daylight is gen- erally not adequate. For media work with projec- tors, windows need to be darkened. And for scientific experiments, a special lighting situation is frequently necessary. However, planning artificial lighting involves more than just ensuring adequate brightness in a room. A differentiated lighting design incorporating vari- ous separately controlled luminaire systems permits the creation of lighting scenes tailored to require- ments. With dimmable room lighting, separate wallwashers at the front of the room and additional luminaires at the entrance Light for learning and perimeter, it is also possible to stage multime- dia presentations, lectures and exhibitions with light- ing fine-tuned for suitability and safety. Today, economical opera- tion of lighting systems is assured by energy-efficient lamps and operating gear, high-grade luminaires with high light output ratios as well as lighting control sys- tems which automatically adjust the brightness of lamps to suit the daylight component available and deactivate lighting when a room is not used. Mod- ernising lighting systems when premises are refur- bished can reduce the annual lighting costs of old school buildings or other educational establish- ments by more than 60%. But lighting design must always focus primarily on human beings, the ac- tivities they perform in the room in question and the visual tasks they need to address. What kind of lighting is needed? How much light is right? And what kind of lighting sys- tem is required to provide it? Lessons conducted from the front of the class call for different lighting than group work, presen- tation area lighting has to cater to different needs than play area lighting, and reading and writing have different lighting requirements than tasks performed at computers or machines. On the following pages, we look at the types of room most commonly encountered in schools and educational establish- ments and present model solutions for them and photographs showing theory put into practice. These are not a substitute, however, for individual lighting planning. 34 7 FGL 3D Visualisation© 8 Classrooms with fixed seating arrangements I n classrooms with fixed seating arrangements, the principal viewing direction is towards the blackboard. The desks here are positioned per- pendicular to the window wall. Room lighting is generally provided by lou- vered luminaires arranged parallel to the windows. The deeper the classroom is, the more rows of lumi- naires are required. With room depths up to eight metres, three rows of luminaires normally suf- fice; in deeper rooms, four or more rows should be planned. Depending on the ceiling system, linear or square louvered luminaires are recommended. With higher ceilings, pendant luminaires with an indirect lighting component are also an option. These ad- ditionally illuminate the ceiling, giving the room a more open, spacious ap- pearance. On an overcast day or in winter, the incident day- light from a window wall is normally not enough to provide adequate illumina- tion for the desks in deeper parts of the room. The rows of luminaires should therefore be separately switched and dimma- ble. The lighting can then be adjusted for uniform brightness throughout the room. Modern luminaires with daylight sensors perform this task and regulate the distribution of light automatically. Where very little daylight is available, all the luminaire rows are activated and set at bright- ness levels which rise with room depth. As soon as the daylight increases, the luminaires are uniformly dimmed down. The blackboard needs to be clearly visible from every desk. Shadows and reflections on the board make it hard to read what is on it and cause visual fatigue. The result: loss of concentration and motivation. Wallwashers with asymmetrical beams provide the right lighting at the front of the room, delivering high vertical il- luminance and avoiding disturbing shadows and reflections. When positioning wall- washers, care must be taken to ensure adequate planar illumination so that the board can be raised and any exten- sions opened without any part of the board being outside the illuminated area. Flipcharts or maps positioned alongside the board should also be uniformly illuminated by the wallwashers. For over- head projector, beamer or TV presentations, the wallwashers should be separately switched and dimmable to enable the illuminance to be adjusted to suit the occasion. Accent lighting can signifi- cantly improve the visual ambience of a classroom. Supplementary wallwash- ers or spots for illuminat- ing notice boards highlight displays in the room and create a more differenti- ated lighting landscape. Additional downlights at the room entrance pro- vide more light for hazard zones and can be linked to the emergency lighting. To help avoid unnecessary, uneconomical lighting, lighting systems can be fit- ted with presence control systems. When a room is vacated, e.g. at break- times or at the start of a free period, the lighting is automatically deactivated and reactivated only when the next person enters the room. Such systems can considerably reduce elec- tricity bills for lighting. 35 36 [...]... the sun tations with projectors can Modern lighting control thus be seen clearly in all systems with daylight sen- parts of the room sors automatically adjust the angle of the blinds and adapt the artificial lighting component accordingly Classes no longer need to be interrupted while someone closes or opens blinds or regulates the room lighting 10 41 42 With lighting control systems, lighting and louver... Where television sets are used, the lighting for the front of the room should be dimmed (Fig 57) 57 ecture 54 Media presentation Lighting control systems facilitate changes in lighting (Figs 51 - 54) At the push of a button, the correct lighting is provided for experiments (52), lectures (53) and TV- or projectorbased media presentations (54) Lighting tips •Bright room lighting facilitates the handling... must also be considered and metal should be for lighting When room avoided Luminaires with lighting is dimmed, steps indirect lighting compo- and exits need to remain nents provide higher verti- illuminated, e.g lit by stair cal illuminance, making lights and an emergency for more harmonious light light over the door Experidistribution, softer-edged ments with fire and inflamshadows and less reflect-... papers As for lighting level, care should be taken to ensure a harmonious 78 79 22 82 80 81 Reading points need to be particularly bright Natural lighting provides adequate basic brightness during the day; an additional reading light on the desk or table makes for greater comfort 84 Lighting tips •Supplementary lighting at bookshelves heightens vertical illuminance •At reading points, lighting needs... workplaces Here, lighting Differentiated lighting with needs to be bright with diverse lighting systems good glare suppression helps structure the room and good colour renderand provides the right ing properties so that food light to create the atmos- and drinks are seen corphere required At group rectly There must be no tables, pendant luminaires reflections on cashpoint for direct/indirect lighting displays... this series, “Good Lighting for Offices and Office Buildings“ 97 98 99 FGL 3D Visualisation© 100 FGL 3D Visualisation© Lighting tips •Staff rooms are workplaces and need to be designed as such The lighting at computer workstations has to illuminate without glare •In large rooms and for meetings, direct/indirect luminaires provide natural, motivating lighting 103 101 102 Lots of light and bright colours... downlights as room lighting and additional light sources beside mirrors, casts faces in a natural light Switches and luminaires need to be protected against splashwater and compliant with the relevant standards 106 30 108 107 109 Lighting tips •Bright ceilings and walls make corridors look bigger and more appealing •Staircases should be provided with glare-free lighting to avoid accidents •Soft light from... 36) 38 40 Daylight decreases with room depth Separately switched and dimmable rows of luminaires make for uniform brightness throughout the room Luminaires with daylight sensors automatically control or regulate light output (Fig 40) Lighting tips •Separately switched rows of luminaires can be activated or deactivated according to the amount of daylight available •Wallwashers for blackboard lighting heighten... facilities are often deserted - yet the lighting is left on, normally just for convenience A lighting control system with integrated presence sensors is very useful here; it is convenient and reliable and it saves energy Sensors switch lighting off when a room or corridor is vacated and reactivate it when the next person enters Energy-efficient use is thus made of artificial lighting and all areas in use are... contained in booklet 4 of this series, “Good Lighting for Offices and Office Buildings“ FGL 3D Visualisation© 62 63 Lighting tips Lighting over desks and in the presentation area needs to be separately dimmable •Daylight incidence through windows needs to be limited by blinds or shades •Luminaires with good glare suppression minimise reflections and direct glare 64 Lighting management systems permit control . lumi- naires. Room lighting thus remains adequately bright while the presentation area lighting is dimmed (Fig. 64). 64 62 63 65 66 Lighting tips • Lighting. way of harnessing natural daylight and the requisite artificial lighting. Here, however, the impor- tance of artificial lighting is often underestimated,