These are all important questions, and some answers can be found in the work of national and international optical radiation safety committees in tackling the LED safety issue. Foundation work in LED safety was put in place as long ago as 2001.
Subsequently, however, a sideline debate has dominated matters concerning whether or not an LED is to be treated as either a "lamp" or a "laser" source. With this debate now concluded in favour of a lamp-based safety analysis, 2008 should be the year when clear guidelines are issued to answer all of the above questions.
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This article was published in the September/October 2007 issue of LEDs Magazine.
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