A Guide for Simulating
Natural Light
in Interior Environments to Maximize the Quality
of Working Life
VITA-LITE -- SHOWN TO ENHANCE THE WORK ENVIRONMENT In a survey conducted
to determine the impact of Vita-Lite in the workplace, three user-dimensions were
examined: (a) evaluation of work environment; (b) evaluation of work task; (c)
evaluation of how subjects felt.
The results show that subjects felt more relaxed and
less fatigued with Viita-Lite than cool white, with
higher eye comfort. Subjects perceived Vita-Lite as
significantly more pleasant, natural, bright, and stimulating.
Additionally, they rated their seeing tasks as more
distinct under Vita-Lite, and their work tasks as easier
and more satisfying.
ENVIRONMENTAL IMPROVEMENT WITH POSITIVE IMPACT Vita-Lite Energizes the
Interior Environment - Natural light energizes the environment for people. They
generally feel better, are more alert, see better and perform better. The mechanisms
for these positive responses to natural light are not completely known. Many of
our customers tell us that Vita-Lite produces similar responses in the ambience
and acceptance of the lighted environment.
FIXTURES FOR VITA-LITE Vita-Lite is available in all conventional fluorescent
sizes and will provide exceptional color and color rendering in all types of fixtures.
For maximum effectiveness of Vita-Lite lamps use the new high efficiency open
type fixtures (with energy saving features and improved glare control), fixtures
with open ("egg crate") louvers, or fixtures with ultraviolet transmitting diffusers...
ideally K-S-H Utran Panels.
VITA-LITE FLUORESCENT TUBE HAS THE PROVEN CAPABILITY
TO:
- Blend with natural light from windows and skylights
- Reveal detail and color accurately. Improve seeabllity
- Render warm, and cool environments equally well
- Help improve the performance and productivity of
people
Vita-Lite is the only patented (U.S. Patent #3,670,193)
general-purpose fluorescent lamp that simulates natural
daylight. This simulation is a major asset toward creating
the perfect interior lighted environment. No other general-purpose
lamp can provide the lighting benefits provided by Vita-Lite.
Vita-Lite was developed and is manufactured by Duro-Test
Corporation, America's largest exclusive manufacturer
of light sources, including incandescent, fluorescent
and H.I.D. lamps.
VITA-LITE PROVIDES ENVIRONMENTAL DESIGN FREEDOM (1) True
Natural Spectrum, Color Temperature, Color Rendering Natural light has the
unique spectrum, which includes a balance of ultraviolet and visible radiation.
The whitest natural light is characterized by a color temperature of about 5000K
+ and a perfect color rendering index of 100. In lighting, natural daylight is
the reference standard for all high color temperature and high color rendering
index (CRI) lamps. It also is the design standard for the spectrum of Vita-Lite.
A general-purpose fluorescent lamp, Vita-Lite, with its color temperature of 5500K
and CRI of 91, is the closest simulation of both the ultraviolet and visible spectrum
of natural light.
The simulation of natural light means that for the
first time environmental lighting with Vita-Lite can
blend perfectly with natural light from windows and
skylights -- an important consideration with today's
increased use of natural light for energy conservation.
This visual system does not have to adapt to a new spectrum,
color temperature or color rendering when one goes from
outdoors or a naturally lighted environment to an indoor
environment lighted with Vita-Lite. Interior colors
are true, and details are rendered accurately with Vita-Lite
as with natural light. Therefore, it is an excellent
source for color and shade matching.
(2) Renders Both Cool and Warm Environments With natural light, cool
or warm environments can be created by choosing the appropriate surface coverings
and furnishings because the natural light spectrum is balanced and complete with
all colors properly represented.
In the past, architects and designers had to associate
cool or warm furnishings with cool or warm fluorescent
lamps. Because of the spectral deficiencies of these
lamps, one had to compensate for the poor color rendering.
But spectrally-balanced Vita-Lite allows design color
freedom.
In addition, the ultraviolet spectrum from natural
light or Vita-Lite causes optical brighteners (used
in papers and fabrics) to increase black and white contrast
and color discrimination. Black and white tasks are
more distinct and sharp. Colors appear more vivid.
Vita-Lite does away with the need to take clothing
or articles to the window to see their true color. Vita-Lite
maximizes what the architect and designer has created.
After all, color is the property of the reflected light
from a surface, and the source of the reflected light
is the light source. It's right if it's Vita-Lite.
VITA-LITE COMBINES PEOPLE CONSERVATION WITH ENERGY CONSERVATION Double
Savings - Since Vita-Lite provides both improved quality lighting plus the additional
benefits of how people feel in an improved environment, the result is both people
and energy conservation.
While electrical energy conservation for lighting
is one of today's major concerns in building renovation
and construction, people conservation is even more important
and cost effective. For example, compare the average
people cost per square foot of office space at $1 50
to that of $1 .25 for lighting cost. With almost 80%
of the lighting cost being energy costs, increasing
the productivity of people 1% is equivalent to an increase
of 135% for lighting energy conservation.
We believe this gain can be achieved with the use
of Vita-Lite because Vita-Lite increases seeability
and improves the work environment. And since Vita-Lite
is available in all typical fluorescent wattages and
lengths, including Watt-Savers, you can, for the first
time, specify for the best of both worlds: people and
energy conservation.
SEEABILITY OVER FOOTCANDLES The complete and balanced spectrum of a
40-watt Vita-Lite lamp produces fewer lumens than the predominantly yellow-green
cool white fluorescent (2180 vs. 3150), but those Vita-Lite lumens are more powerful
and energetic for visual and physical activities. We use the word "seeability"
to describe the human factors effects in Vita-Lite spectrum and lumen output.
"Seeability" is a non-technical term, which describes how well the eye sees. It
includes the ability to define form, which is a primary function of the eye, but
it also includes color discrimination, color rendering and influences on physical
activity. In reality, the reaction of the body is greatly influenced by these
and other factors, which make up seeability. Footcandle level, while a measurement
of light quantity, is not the indicator of real seeability.
The concept that the footcandle or lumen does not
adequately define light for visual acuity is well documented.
Light from high-color rendering lamps such as Vita-Lite
provides enhanced seeability and visual effectiveness
even at lower footcandle levels than is obtained with
standard high-lumen-output lamps such as cool white.
Vita-Lite lamps can be specified and substituted in
installations using conventional lamps on a one-for-one
basis and still improve seeability.
Any task that is adequately lighted with cool white
or warm white will have improved seeability under Vita-Lite.
Vita-Lite is then the ideal replacement for cool white
or any other fluorescent lamp, wherever they are used.
In calculating the number of lamps required for task
and area lighting (using the recommended illumination
levels in the Illuminating Engineering Society Handbook
Applications Volume, 1981) simply use lamp data for
cool white lamps and then substitute them with Vita-Lite
lamps in the lighting system. This technique provides
a lighting system with the same installed wattage and
with enhanced seeability.
SPECIFYING VITA-LITE To specify Vita-Lite,
use this table:
Vita-Lite or equal light sources shall simulate the
full visible and balanced ultraviolet spectrum of natural
light for use in general indoor illumination as follows:
| Correlated Color Temperature: |
5500K |
| Color Rendering Index: |
90 or greater |
| Near Ultraviolet Radiation: |
(UVA, 320-380nm) 254 +/- 51uw/lumen |
| Middle Ultraviolet Radiation: |
15 +/- 4 uw/lumen |
| Near UV/Middle UV Ratio: |
11 - 28 |
|
A Guide for Simulating