Great question!
While most sunlamp manufacturers list a rated lamp life for their products, few say what their method is for determining that rating. Is it the number of “lamp on” hours after which you should expect it to burn out? Is it just a number printed to justify their compatibility claims? Is it that point when the lamp’s UV output has decreased by 50 percent?
At Wolff System and JW North America, we consider a sunlamp’s rated service life to be that point when UV output has depreciated by 30 percent from its initial levels. A well-constructed sunlamp, properly applied in a tanning system, will be ready for replacement due to this natural output (phosphor) depreciation well before it fails to “light.” This is a forecast of lamp performance under proper operating conditions. We all know that running sunlamps at higher temperatures will shorten their service life (phosphor degradation) AND their physical life (burnout).
Sunlamps experience their sharpest decline in output during the first 50-100 hours of use. Therefore, insist on knowing the rated life from zero hours, since that is how you will employ them in your tanning equipment. Higher-quality phosphors tend to be more stable and last longer. During the first 50 hours of a lamps use, consider reducing your salon guests’ allowable exposure time by five to ten percent, so that your tanners do not experience an unexpected result from their UV session.
Remember, due to variables such as maintenance procedures, equipment ventilation and voltage irregularities, the actual service life of a sunlamp can, and often does, differ. Again, the best way to manage this aspect is good equipment maintenance and regular monitoring of output. Invest in and use an economical, hand-held radiometer and record the test results. Replace depreciated sunlamps before your tanners start to complain about their results.
A well-constructed sunlamp, properly applied in a tanning system, will be ready for replacement due to natural output (phosphor) depreciation well before it fails to “light.”
To maximize lamp output and useful life:
- Start with a high-quality product.
- Regularly clean and replace acrylic shields according to the manufacturer’s specifications.
- Clean reflective surfaces behind the lamps periodically and / or when you re-lamp.
- Replace worn starters before they cause re-strikes or fail entirely. Worn starters can destroy a good sunlamp in a noticeably short time.
- Maintain proper tanning room temperatures with adequate air conditioning and ventilation in your facility.
- Higher ambient temperatures can shorten a lamp’s service life and reduce UV output.
- Incoming voltage to the tanning system must meet the manufacturer’s specifications. Insufficient voltage will reduce tanning effectiveness, while high voltage may reduce lamp life.
- Keep in mind that VHO (very high-output) lamps tend to have a shorter life than HO (high-output) lamps.
- A vertical application (booth) is harder on sunlamps than horizontal (beds).