Hello Brian,
It’s my experience that as the brightness of LED indicators increase, they 
become distracting and annoying way before they come anywhere near being 
hazardous. If your indicators are so bright as to even think they could be 
hazardous, I’d be asking myself why they’re so bright in the first instance.
I have two pieces of equipment at home with small squares of black tape over 
stand-by (red) and power (blue) LEDs.
Tell your engineers that it is OK to drive LEDs at less than 20mA!
Regards,
Tony
----- Original Message -----
From: Kunde, Brian
Sent: 01/13/14 02:56 PM
To: [email protected]
Subject: [PSES] LED Indicator Safety

Greetings to all. I'm being asked by Engineering regarding the brightness of a 
Green LED Indicator they want to use on the front of an upcoming product. The 
LED is quite bright and is used with a Light Pipe which shows through the front 
panel. However, if you remove to front panel to perform a maintenance operation 
while the unit is still turned on (which is desired) you can see the LED. If 
you look directly at the LED it is bright and hurts to look at it for more than 
a second. However, you would have to deliberately look directly at it to 
receive the full brightness. At normal angles and distance the light causes no 
discomfort to look at it. The IEC/EN/UL/CSA 61010-1 safety standard only 
includes information about UV light. The EUT is classified as Laboratory 
Equipment. My Google research mentions the standard IEC 60825 and IEC 62471 and 
test method ANSI/IESNA RP-27. Would it be helpful to read these standards 
without having the test equipment to test it? For visible light!
  such as this isn't there a simple test method such uses a basic light meter 
to determine if a hazard exists or not? Are LEDs classified by the manufacturer 
for their "Risk Group"? What Risk Group can I use and declare it not hazardous? 
Sorry for being such a NUBE on this topic. I know this topic has been discussed 
in the past but I was hoping new LIGHT might have been shined on it recently 
with all the new super bright LEDs on the market. Thanks in advance. The Other 
Brian ________________________________ LECO Corporation Notice: This 
communication may contain confidential information intended for the named 
recipient(s) only. If you received this by mistake, please destroy it and 
notify us of the error. Thank you. - 
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