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I have a compliance audit that has been foisted on me from on high - as part of what an external consultancy has highlighted, I now have to prove that the indicator LEDs on a board I designed a long time ago are Class 1 laser compliant. Please do not point out how ridiculous this is.

I have the following specs for the LEDs in question:

  • peak wavelength (595 nm)
  • dominant wavelength (590 nm)
  • spectral bandwidth (15 nm)
  • luminous intensity (120 mcd)
  • viewing angle (defined as the angle across which luminous intensity is 50% or more of maximum - 140º)

Link to datasheet.

The Wikipedia article on laser safety has this chart of maximum allowed CW power at various wavelengths and for various classes. It states that it is only valid for weakly divergent or collimated laser beams, but since Class 1 devices must be safe to view using any optical equipment, I can make the assumption that they are valid for the case where there exists a lens that can concentrate all of the available optical power from the LED onto the retina.

My big issue is that I can't seem to work out how to go from luminous intensity to optical power. I can convert from luminous intensity to luminous flux - however not to radiant flux (which I believe is equivalent to total optical power).

Can anyone shove me in the right direction?

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    \$\begingroup\$ An LED is not a laser -- it's as simple as that. You can concentrate the light from any noncoherent source (even an incandescent bulb) into the eye, but that doesn't make it a laser safety compliance issue. If you play along with their game, you're just encouraging the silliness. \$\endgroup\$ – Dave Tweed Apr 13 '17 at 11:08
  • \$\begingroup\$ Thanks Dave, and I agree. However I believe that high power LEDs do come under the legislation and by extension the burden is on me to prove that my LEDs are not high power. \$\endgroup\$ – stefandz Apr 13 '17 at 11:10
  • \$\begingroup\$ You need to find the specific regulations that they're citing and read them for yourself. \$\endgroup\$ – Dave Tweed Apr 13 '17 at 11:13
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    \$\begingroup\$ Light emitting diodes (LEDs) have been deleted from the scope of this document except for communication applications. LEDs are covered by IEC 62471 \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Apr 13 '17 at 11:43
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    \$\begingroup\$ ancient history (10yrs ago) , get the right specs and it will tell you \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Apr 13 '17 at 11:48
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Light emitting diodes (LEDs) have been deleted from the scope of this document IEC 60825-1 in 2007, except for communication applications ( very high intensity light focused beams).

LEDs are covered by IEC 62471 for Class 1, 2, 3.

I suggest you ask for the correct requirements. ( ie. spec)

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  • \$\begingroup\$ Just found a caveat to this. The original auditors came back and had mistakenly identified our product as a toy. Apparently, with toys the old IEC 60825-1 is still applied (ridiculously). From EN 62115: "EN 60825-1:1993 and its amendments are superseded by EN 60825-1:2007, which is based on IEC 60825-1:2007 and by EN 62471:2008, which is based on IEC 62471:2006. However, for LEDs in toys a product standard based on ICNIRP Recommendations is in preparation and therefore EN 60825-1:1993 and its amendments will have to be used until this standard for LEDs in toys is implemented." \$\endgroup\$ – stefandz Apr 13 '17 at 16:34
  • \$\begingroup\$ Is it a toy or a mistake? If so, and, it is exempt from \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Apr 13 '17 at 22:42
  • \$\begingroup\$ In my case I am fine - it is their mistake. Just wanted to add the note for future visitors. \$\endgroup\$ – stefandz Apr 13 '17 at 22:43
  • \$\begingroup\$ If it were so, it will be Class 1 (safe) and, it is exempt from hazard symbol label. 5mm LEDs are only rated for 20mA , and since it is Yellow (590nmD) it will be 2.1V nom and thus only 42mW of heat and light and luminous power with 120 mcd @140deg since similar 140 deg Yellow LEDs are capable of >1,000 Cd in 5mm , if we incorrectly assumed the efficacy was 100%, which is far reality , it could not possibly exceed 5mW of optical power and is more likely <0.5mW \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Apr 13 '17 at 23:07

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