The eye typically does have some sensitivity to near-IR. However, because
it "appears" dim, the iris does not close as it should to protect the eye.
Here is some info I've found on IR safety.

http://www.axis.com/products/cam_irillum/files/Eye_Safety_with_Near_Infra-R=
ed_011107.pdf

IEC62471 does include radiation from LEDs. Quoting from a UL notice, "To
address these hazards, UL's services incorporate photobiological testing
of LED products. The primary purpose of this testing is to protect the
skin and eye from potentially harmful optical radiation."

http://sci.tech-archive.net/Archive/sci.optics/2005-04/msg00399.html shows
a sample calculation of intensity in mw/cm2 based on an LEDs irradiance in
mw/sr and the distance from the LED. That formula works out to:

d=3Dsqrt(N*LED/I) where

    d is distance in cm
    N is number of LEDs
    LED is the LED irradiance in mw/sr
    I is the intensity in mw/cm2

IR Safety Glasses Info.

The optical density rating is the base 10 log of the power density
attenuation at the specified wavelength. For example, an OD of 1 would
reduce 1W/m2 to 100mW/m2.
Suppliers

    Thor Labs http://www.thorlabs.us/NewGroupPage9.cfm?ObjectGroup_ID=3D762
    No IR http://www.noirlaser.com/lasershields/infrared.html

Harold


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