Factors that influence the operation of the UV lamp
Three main factors influence a UV lamp's life-span:
Type of lamp: life-span of LP lamps is usually double--and sometimes three times--that of MP lamps.
Operation mode: one of the most critical factors to determine a UV lamp life is the number of ignitions. During operation, the UV system might be turned on and off frequently. This dramatically influences the performance of the lamp and consequently accelerate its decay and resulting in a much shorter life-span than officially stated by the manufacturer.
Operating temperature: LP lamps are very sensitive to their operating temperature. Changes above or below the optimal operating temperature (about 38°C) affect their output and consequently the effective life-span. MP lamps are generally not sensitive to temperature, and changes in operating temperature do not affect their output.
Regardless of what is stated by the UV manufacturer, the only way to be certain that the UV lamps are working properly and can deliver the required UV dose is by ensuring that the UV system has a dedicated UV sensor for each individual lamp. The manufacturer's stated hours of operation should be used only as a reference.
Lamps should be changed according to their performance. If a lamp's efficiency (the amount of power it generates) is not sufficient for delivering the required UV dose, it must be replaced immediately. For this reason, each and every lamp should be monitored independently, by a dedicated UV sensor, for reliable and accurate lamp status indication at all times.