Design of Artificial lighting in workplace.

2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES)

Design of Artificial Lighting in Work Place
N. Adiputra1, DP. Sutjana2, PG. Adiatmika3, Alit Swamardika IB4
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

Copyright of this paper

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.

MATERIALS AND METHODS

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.

RESULTS AND DISCUSSION

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

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.

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.

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.


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.
b.

c.
d.
e.

Economic. If the economic considerations are power
(W) then Luminous efficacy (lm/W) to be used should
be a consideration.
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.
An auxiliary tool required, for example: armature,
controller.

The effects that might be brought about, among other
things: shadow, stroboscopic, glare.
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.
b.
c.
d.
e.
f.

The drawing of a room, the dimensions of a room, and
the plan of the layout of the lights.
Details of the construction of the ceiling.
Color and reflections from: ceiling, wall, floor and

Desk Chair (furniture that is in the room).
The function of the room (a visual work that will be
done in the room)
Equipment machinery or equipment in the room.
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

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
where is :
E = The intensity of illumination in work areas, in lux;
A = the dimension of room (p x l) in m2

(1)

2012 Southeast Asian Network of Ergonomics Societies Conference (SEANES)



g
o

(2)

where is:
Фo = the flux of light emitted by all sources of light in the
room;
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.

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]:

n

ExA
.
lamp x  x d

(4)

For an example: The office room are 6 x 3 x 3,5 m, was
planned to be put on TL’D 2 x 36 watts with E = 500 lux
illumination. Calculate the number of lights needed.
Solution:

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].

Total lumen = 2 x 2850 = 5700 lumen (ex. philips catalogue)
The depreciation factor d = 0.8
rp = 0.5 (light-colored)
rw = 0.3 (light-colored)
rm = 0.1 (dark-colored)

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
square-shaped room [4]:

k

p.l
.
h( p  l )

where is:
p = length of the room, in m;
l = width of the room, in m;

(3)

the working plane = 0.8 m ( so h = 2.7 m)
Room index is;

k
then : for

6 x3
.  0.74
2.7(6  3)

k = 0.6 ;  = 0.22
k = 0.8 ;  = 0.29

so, for

k = 0.74 ;  = ?

  0.6 

0.74  0.6
(0.29  0.22)  0.65
0.8  0.6

Hence number of lamps required =
500 x 18
n
.
5700x 0.65x 0.8
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.

2.

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.
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]
[2]
[3]
[4]
[5]

Amstrong, “Australia: Occupational Health & Safety Authority”, R.
Lighting at Work, Melbourne, 1992.
P. Manurung, “Desain Pencahayaan Arsitektural Konsep Pencahayaan
Artifisial pada Ruang Eksterior”, Yogyakarta: Andi Offset, 2009.
Muhaimin, “Teknologi Pencahayaan”, Bandung: PT, Refika Aditama,
2001.
P.V. Harten and Setiawan, “E. Instalasi Listrik Arus Kuat 2”, Jakarta:
CV, Trimitra Mandiri, 1999.
P. Satwiko, “Fisika Bangunan”, Yogayakarta: Andi Offset, 2009.