When There's No Cure

Another approach that Naughton says is available from EIT and is in the moderately priced range is the use of relative intensity monitoring. With these systems, relative intensity is measured starting with the installation of a new bulb. The sensor is set at 100 per cent and as the bulb degrades, the system continuously monitors the intensity as it decreases. Typically, the bulb should be changed when it reaches 60 per cent of its original intensity.