Photobiological Safety Compliance Standard RP-27.3
As with any S ¯olarc product, UV precautions must be
taken when directly handling the lamp. Ultraviolet, visible
and infrared radiation are emitted from metal halide lamps.
Possible skin or eye irritation can result from exposure to
the output of a 21 W S ¯olarc lamp exceeding 15 minutes in
one day. Use appropriate personal protective equipment.
Do not stare at an exposed lamp in operation. Due to the
extremely high brightness of the lamp, proper attenuating
glasses must be worn when directly viewing the bulb.
During operation, the lamp should be enclosed in a
housing to prevent injury in the circumstance of the
lamp shattering.
Handling
Ballast products are electrostatic sensitive electronic assemblies
and should be handled as such. Proper electrostatic discharge
(ESD) handling procedures must be employed.
Protect the quartz arc tube when handling the lamp.
The arc tube may be protruding from the end of some
reflectorized lamp assemblies. Keep the arc lamp clean.
Do not touch the quartz tube, the inside surface of the
reflector, or the connecting wires. Contamination can
degrade lamp performance or cause premature failures.
If necessary, clean the lamp by wiping with a lint-free
towel or cotton swab immersed in denatured alcohol.
The high-intensity light at the front of the light source and
possibly at the tip of the fiber optic bundle, if used, may
give rise to bright light and high temperatures. To minimize
the risk of injury, avoid direct viewing or contact.
Disposal
S ¯olarc lamps contain a small amount of mercury—usually
no more than found in typical fluorescent lighting.
Disposal and handling must conform to local regulations
and hazardous waste disposal guidelines.
Do not remove lamp from equipment until it has cooled.
Never handle the lamp when it is operating!
The industry standard for reporting lamp life is median
hours—the point at which 50% of the lamps have stopped
operating satisfactorily. Generally, a lamp is considered to
have failed if it no longer starts or the lumen output has
fallen to half of its initial value. Welch Allyn defines a
rated “median life” for all its lamps. This is a statistical
determination—based on periodic testing—of the median
operating time for randomly selected groups of lamps.
One half of the lamps will continue to operate beyond this
median life while others will reach their end-of-life earlier.
The predominate symptom of end-of-life is the inability to
start the lamp. Once a lamp has started, one can generally
count on that lamp continuing to operate throughout a
given procedure, however there is a possibility that the
lamp could rupture. For that reason, lamps should be
installed in an enclosure.
To fully characterize lamp life, one must also define a
duty cycle. Duty cycle is how often a lamp is turned on
and off. S ¯olarc lamps are typically tested in the laboratory
with a duty cycle of one or two hours on and 15 or 30
minutes off. More frequent cycling will reduce the lamp
life. For instance, turning the lamp off every 10 minutes
may reduce rated life as much as 50%. Conversely,
operating the lamp in a continuous mode may extend
life up to 30%.
Lamp life will also be decreased if the lamp is operated
above designed operating temperatures. (Please refer to
Lamp Temperature & Cooling on page 9.) It is important
that the equipment designer ensures that the maximum
operating temperature is not exceeded and that free airflow
is available at all times.
Figure 9 (page 14) depicts a graph of lumen maintenance
versus life for the 21 W lamp. This data was taken with
the lamps operating in their standard duty cycles at
rated wattage. Performance can vary substantially under
different operating conditions. You should always qualify
performance for the specific operation that you design.
In Figures 10–13 (starting on page 14), you will find
graphs indicating the color stability of the lamp. The first
pair of plots indicates X and Y chromaticity deviation
versus life, while the second set of plots show a spectral
distribution taken from a typical lamp when new and after
a period of time. S ¯olarc lamps will maintain a high level
of both chromaticity and light intensity throughout
their lives.
LAMP SAFETY, HANDLING & DISPOSAL
cont’d
LAMP LIFE & MAINTENANCE
6
