How long do Pen-Ray Lamps last?
The lamps are rate for 5,000-8,000 hours but can last up to 16 years (documented) depending on use and applications. Generally the more startups imposed on the lamps (as opposed to continuous use), the shorter the life due to wear on the electrodes as a result of the initial spark needed to ignite the lamps. In the case of Mercury lamps, the primary emissions peak at 254nm will decrease steadily with time due to quartz solarization. This will yield a net output of approximately 70% after 2,000 hours. The effect will then stabilize for the remainder of the life of the lamp.
