2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES)
Design of Artificial Lighting in Work Place
N. Adiputra
1, DP. Sutjana
2, PG. Adiatmika
3, Alit Swamardika IB
4 Dept of Ergonomics, Faculty of Medicine, University of Udayana, Bali, Indonesia{1nadip2003, 3ipgadiatmika, 4alit_bbc}@yahoo.com
Abstract- According to many studies, the use of artificial lighting in a room is larger than the use of natural lighting. Thus needs to be done to design accurately for the required lighting levels by utilizing the optimal energy. Designing lighting is done by determining the number of lamps needed, adapted to the type of work performed in the room. One important aspect in planning artificial lighting in the work place is the application of ergonomic aspects. The objective of this study is to describe how to determine the amount of lights are needed in a room with implementing aspects of ergonomics. To achieve this objective, a study using literatures from various sources was carried out. Calculation of the lighting are influenced by several factors such as, the function of rooms, the type of lamps, dimension of the rooms, color of the walls, color of the ceiling, color of the floors, furniture, and the type of task. By consideration of the ergonomic aspect in the planning of artificial lighting in the workplace, errors that may occur are expected to be reduced systematically.
Keywords: the number of lamps, design of artificial lighting, ergonomic aspects.
I. BACKGROUND
The light intensity is very essential for daily human activity. The main function of the lighting system is providing a visual environment that is comfortable [1].
Poor illumination can lead to a tiredness of the eyes or nervous tension. Glare affect the inability the eye to respond the light or an uncomfortable feeling of excessive are caused contrast. The inability to respond a momentary light can happen to change luminance flashily, for example: from the dark to a state of sudden light when the car was light through. Changes of illumination intensity suddenly require adaptation of the eyes for a while is called Adaptive glare [3].
So the importance of light for the human activity, then it is not surprising if the design of lighting on building also holds a vital role for the success of the function of the building. Based on some researches, the use of artificial lighting in the room is larger than the natural lighting. In General, artificial lighting is currently used when the natural lighting are at minimum power or less eligible [2].
Sadly, in many cases the ready availability of artificial lighting as an engineering solution has disassociated both building designers and users with their ability to use daylight as the predominant/sole light source when appropriate.
From the description above, planning artificial lighting is an effort to obtain a design that can fulfill a need a light according to need for human activity in the room so that its activities could be running as expected. One of the important
aspects in the planning of artificial lighting in the room is by implementing of the ergonomic aspects. The planning of the artificial lighting is done by determining the quantity of lamps adjusted to the room function.
II. MATERIALSANDMETHODS
A. Materials
The materials in this paper are design of artificial lighting in workplace reviewed from the ergonomics aspects.
B. Methods
The method used is the literature review. III. RESULTSANDDISCUSSION A. Artificial Lighting
Wherever, whether in the house, industry or office, the lighting in accordance with the type of work will make all task of being easily. Human being receives approximately 85 per cent the information through the sense of vision. Good lighting, without glare or shadow, can reduce eyestrain and headaches. It also reduce the possibility of an accident and injury when adapting to environmental that lighter or darker [2].
Light makes everything that exists in the surrounding environment has visual information so that the brain is able to translate it and generate specific response. The aesthetics inherent in an architectural design will be capable of being received by the eyes due to the presence of light. The lighting was very important because most of the information is sourced on the sense of vision.
The quality of illumination is really subjective; it is determined by the feelings resulting in each individual. To that end, in measuring the quality of illumination, a designer can make an approach on visual response through observation and research. With that response, the designer can determine the quality of illumination that exist [2].
Artificial lighting is needed if the position in the room is difficult or insufficient to be achieved by the natural lighting. Aartificial lighting has many unique benefits:
1.Light can be available whenever it is required e.g. outside of daylight hours
2.Light can be provided wherever it is required e.g. in areas far from the building envelope. This has had a radical impact on the possibilities of form in modern architecture.
2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES) 3.Light can be provided however it is required i.e. in any
quantity and with any distribution. This can be tailored to provide a variety of requirements e.g. task lighting, display lighting, general ambient lighting
4.The light provided is stable in output, unlike daylight, so where precise control is required of light quantity and quality e.g. color, this can be guaranteed with an artificial system.
5.Light can be provided independently of increased heat loss and gains from windows
A few things to get attention for indoor lighting designer among other things are [3]:
a. Economic. If the economic considerations are power (W) then Luminous efficacy (lm/W) to be used should be a consideration.
b. Lifetime. The lifetime of the lamp can be made into consideration replacement lights only when there are lights that are dead and how economical replacement for groups.
c. An auxiliary tool required, for example: armature, controller.
d. The effects that might be brought about, among other things: shadow, stroboscopic, glare.
e. Color the walls of the room. Because the reflection of color the walls also affect the comfort.
To get the adequate quality of illumination source of illumination and environmental factor should be considered. Therefore the lighting designer needs the necessary data. The necessary data for planning a lighting installation are [3]:
a. The drawing of a room, the dimensions of a room, and the plan of the layout of the lights.
b. Details of the construction of the ceiling.
c. Color and reflections from: ceiling, wall, floor and Desk Chair (furniture that is in the room).
d. The function of the room (a visual work that will be done in the room)
e. Equipment machinery or equipment in the room. f. The conditions of the rooms such as: temperature,
humidity, and dust. B. Design of Artificial Lighting
Designing an artificial lighting system, as with any process of design, involves resolving a series of often conflicting objectives. It is vital that the client expresses their priorities to the design team, and that in term the design team is capable of expressing the potential conflicts and compromises that may result.
The quantity of lighting is an attempt to meet the needs of the functioning of the room. Functional requirements are very closely related to the activities that occur in this room. Different from the quality of lighting that is oriented to the creation of visual appearance, the quantity of lighting more on terms of visual work [2].
The quantity of light needed by each person would be different, it is very relating to conditions and the background of the person. Age factor would be very influential on the
ability of people to see in certain light conditions. The older the age of a person, also declining in the eye's ability to respond to the light so that the need for the quantity of light will be even greater when compared with younger age.
The lighting system in the room is divided into 5 types; 1. Direct lighting: In this system the 90-100% of the light
is directed directly to the object that needs to be illuminated. This system was considered most effective in regulating lighting. For optimal effect, it is recommended the ceilings, walls and objects that exist in the room need to be bright colors.
2. Semi direct lighting; In this system is 60-90% of the light is directed directly at the object that needs to be illuminated, while the rest is reflected to the ceiling and walls.
3. General diffuse lighting; In this system is 40-60% of the light is directed directly at the object that needs to be illuminated, while the rest is reflected to the ceiling and walls.
4. Semi indirect lighting; In this system is 60-90% of light directed to the ceiling and the walls of the upper, while the rest are directed to the walls of the bottom. 5. Indirect lighting: In this system the 90-100% of the
light is directed onto the ceiling and walls of the top then reflected to illuminate the whole room.
Calculating the needs of illumination in a room is not easy. To determine accurately, is usually performed by professionals in the field of lighting. This aims to calculations amount of the light are used according to needed. If lacking or excessive, besides wasteful, also causes discomfort in the eye. Good lighting is essential so that the work can be done properly and in a situation which is convenient.
Good lighting is that allows a worker see jobs with a thorough; fast and without any unnecessary effort, as well as help create a pleasant working environment. Traits of a good lighting is determined by the distribution of luminance in the sight field, prevention glare, direction of light, color and the heat of lighting on the state of environmental.
The first step is done in design of a good lighting is to know the function of rooms. Then calculate the dimension of room, the height of ceiling and the high areas of work from the top floor. The work area's is an area that most used to have activity in these rooms. In the workplace, for example, the activity of writing and reading on the table, is the most often done. The height of the desk, that would be became the benchmark in high of work area's [3][4].
The intensity of the illumination E is expressed in units of lux, equal to the sum lm/m2. So the flux of the light needed for a work of covering an area of A m2 is [4].
Ф = E x A lm (1)
where is :
2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES)
Фg = the flux of light that reaches the areas of work, directly or indirectly after being reflected by a wall and the ceiling.
To determine the efficiency of lighting, the factors to be taken into account is:
a. The efficiency of the armature (v);
b. The reflection factor of the walls (rw), the reflection factor of the ceiling (rp), and the reflection factor of the work areas(rm);
c. The room index.
The factors of rw and rp each declare the reflected flux of light received by the walls and the ceiling, and then reach the areas of work. the reflection factor of the work areas(rm), determined by the reflection of the floor and the reflection of the wall between areas of work and the floor, generally value of rm are chosen 0.1 [4].
The ceiling and the walls of colored light reflectance of 50 - 70 %, and dark-colored 10 - 20 %. The influences of the wall and the ceiling on the direct lighting systems are smaller than its influence on other lighting systems, for the light that falls on the ceiling and walls are just a small part of the flux of light.
Like most devices, lamps lose some light output over their rated life. The gradual loss of efficacy (lumens per watt) is called lumen depreciation. Lumen depreciation in lamps is caused by two main factors, loss of chemical additives in the lamp and wall darkening in the arc tube. In the arc tube are chemicals that are responsible for the generation of light. As the lamp operates, these chemicals react with the arc tube components and eventually can no longer produce light. Also, the standard arc tube contains two tungsten electrodes that are heated to incandescence during lamp operation. When the lamp is started, these electrodes evaporate tungsten which deposits on the inside wall of the arc tube. These black deposits absorb light and cause the amount of light emitted by the lamp to decrease. Both of these are very gradual processes, but the end result is a loss in efficacy for the arc tube
The room index k is a comparison between the size of a
h = Height of the luminaire measured from the working plane such as top surface of a desk, in m.
The room index is necessary to know the needs of the amount of illumination. The working areas are an imaginary horizontal plane, generally is 0.8 m above the floor.
To determine the number of lights a room can be calculated as follows [4]: illumination. Calculate the number of lights needed.
Solution:
Total lumen = 2 x 2850 = 5700 lumen (ex. philips catalogue) The depreciation factor d = 0.8
rp = 0.5 (light-colored)
Hence number of lamps required =
n = 3 lamps
From the example above, considering all the aspects that influence the quantity of lighting in the workplace, then the number of lamps that will be obtained in accordance with the activity of the people in the room.
By implementing the ergonomic’s consideration such as, the function of room, the type of lamp, color of the walls, color of the ceiling, color of the floors, furniture, and type of task, then the design of artificial lighting in the workplace in accordance with the needs of the human activities in the room.
2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES)
IV. CONCLUSIONS
From the discussion above, some conclusions could be drawn as follows:
1. The design of the artificial lighting is an attempt to get a design that can meet the needs of light corresponding to the need for human activity in a workplace.
2. By implementing the ergonomic’s consideration, such as the function of rooms, the type of lamp, the dimensions of room, color of the walls, color of the floors, color of the ceiling, furniture, and the type of task, so the design of artificial lighting can meet the needs of human activity in a workplace.
REFERENCES
[1] Amstrong, “Australia: Occupational Health & Safety Authority”, R. Lighting at Work, Melbourne, 1992.
[2] P. Manurung, “Desain Pencahayaan Arsitektural Konsep Pencahayaan Artifisial pada Ruang Eksterior”, Yogyakarta: Andi Offset, 2009. [3] Muhaimin, “Teknologi Pencahayaan”, Bandung: PT, Refika Aditama,
2001.
[4] P.V. Harten and Setiawan, “E. Instalasi Listrik Arus Kuat 2”, Jakarta: CV, Trimitra Mandiri, 1999.
