With the eventual phase-out of traditional mercury vapor lamps, there is a need for consistent specifications covering
alternative UV-A sources, such as LEDs. Traditional radiometers and luxmeters are insufficient to properly characterize UV-A
lamps, and an ASTM Task Group has been formed to determine the correct procedures. This paper will show the kinds of
tests used in characterization of UV-A lamps (including LEDs), typical data from several manufacturers, and explain why the
use of a properly designed UV-A LED lamp is important for successful penetrant and magnetic particle examinations.
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