Applicability of 5× maximum permissible exposure limit for near-infrared laser directed energy weapon hazard zones

The authors review the underlying safety aspects of maximum permissible exposure (MPE), defined as the level of laser radiation to which an unprotected person may be exposed without adverse biological changes in the eye or skin, in laser safety, as well as the rationale behind the Class 3R laser classification so as to propose using a more relaxed exposure guideline for the use of laser directed energy weapons. Based on the unique constraints applicable to laser weapons as well as the inherent safety factor built into the maximum permitted exposure, the authors recommend allowing 5× MPE as the hazard zone guideline.