UFC 3-530-01
22 August 2006
5-3.1
Lamp Comparisons. Table 5-4 compares lamp types based on the following
characteristics: efficacy (lumens of light per watt of energy), lamp life (the expected
time of operation until 50% of the lamps are out), color temperature (the color of light
emitted from the lamp), color rendering (how the light from the lamp shows other
colors), start (time until the lamp is at full brightness), lumen maintenance (how the light
output decreases over the lamp life), effects of ambient temperature on the lamp, and
cost. This comparison illustrates that there is no "best" lamp. Choose lamps based on
the criteria that are most appropriate to the project. Efficacy may be the guiding criteria
to save the most energy; color rendering may be the most important issue in an area
where colors will be viewed; or lamp life will be critical in hard to maintain areas.
Table 5-4. Comparison of lamps.
Efficacy
Color
Lumen
(lumens / Lamp Life Color Temp. Rendering
Start
Maintenance
Dimming
Initial
watt)
(hours)
(Kelvin)
Index
Time
(%)
Capabilities
Effects of Temperature
Cost
Compact
with dimming
longer start and warm-up
60 - 75
10,000
2700 - 4100
82
0
83 - 87
Med
time in low temperatures
Fluorescent
Linear
with dimming
longer start and warm-up
80 - 95
20,000
2700 - 4100
75 - 85
0
83 - 87
Low
time in low temperatures
Fluorescent T8
full output only at 35
Linear
degrees C (95 degrees F).
with dimming
Fluorescent
80 - 95
20,000
2700 - 4100
75 - 85
0
90 - 95
Lower temperatures
Med
increase start time and
T5HO
light output
will soon be
low temperatures
Very
60 - 75
100,000
3000 - 4000
80+
0
80
developed
decrease light output
High
10,000 -
yes, but
Metal Halide
80 - 90
3000 - 4200
65 - 90
5-10 min
80 - 85
none
High
expensive
20,000
High Pressure
90 - 105
24,000+
1900 - 2100
21 - 85
<5 min
88 - 92
none
none
High
Sodium
Low Pressure
100 - 160
16,000
1800
poor
7-15 min
100
none
none
Med
Sodium
Mercury Vapor
35 - 55
24,000
4000 - 5900
20 - 45
<10 min
60 - 65
none
none
Med
varies by
high and low ambient
varies by
color (up
varies by
varies by
with variable
temperatures may
LED
0
High
color
to
color
color
power supply
adversely affect lumen
100,000)
depreciation and life
Tungsten
2000 -
18 - 22
2800 - 3100
100
0
93 - 97
dimmable
none
Low
4000
Halogen
1000 -
Incandescent
15 - 18
2700 - 3000
100
0
83 - 87
dimmable
none
Low
3000
5-3.2
Lamp Efficacy. Lamp Efficacy is the number of lumens produced by a lamp
per watt of electrical input. This quantity allows for a comparison between lamps and
lamp wattages. Linear and compact fluorescent lamps have a high efficacy, which is
several times higher than incandescent lamps (general service light bulbs). Choose the
highest efficacy lamp that still meets the visual requirements for the application. Also,
consider "effective lumens" (see paragraph 2-5.2.5) for exterior lighting applications.
5-8
Previous Page
