Product Code: ILSC2011_401

How to Select Laser Protective Eyewear
Authors:
James Sheehy, Naval Aviation Enterprise; Patuxent River MD USA
Christine Stanley, Naval Air Warfare Center Aircraft Division; Patuxent River MD USA
Presented at ILSC 2011

A common misconception often heard is that if its a (fill in the color) laser; wear the same color Laser Eye Protection (LEP) definitely not the right approach. This presentation will discuss a simple approach to selecting protective eyewear. The first step is to ask a few basic questions such as, what wavelength or wavelengths, is the laser pulsed, continuous wave, whats the expected power output, am I indoors lights on or out? After answering these questions, the next step is to determine what optical density (OD) is required. A simple first step would be to calculate the Maximum Permissible Exposure (MPE), Nominal Ocular Hazard Distance (NOHD) or Nominal Skin Hazard Distance (NSHD) (ANSI 136.1, 2000) using the laser parameters. Err on the safe side, round up when in doubt. Another common misconception is that the more wavelengths of protection the LEP provides the better. This could be more of a hindrance than benefit. The critical factor here is the environment in which the LEP will be used; in or outdoors, day or night, lights on or off, reflective surfaces, the need to be compatible with instrument panels or certain colors in display panels. When using LEP outdoors during day light hours certain absorptive dyes do not retain their protection levels when exposed to solarization and therefore the question becomes should reflective eyewear be considered over absorptive technology? The optimal choice will be the LEP that provides the best protection while affording the best visual acuity (absorptive verse reflective or combination of both technologies). Once you have all this information in hand the last questions deal with what style of LEP will work best? Does it have to be compatible with head gear? Will spectacles work, or is there a need for something that provides more protection from reflection such as side shields or goggles could provide. So unfortunately there are many considerations that need to be weighed carefully when determining the proper LEP for your situation, but using a simple approach are easily determined, and yes green eyewear is not necessarily good for a green laser.