This webinar discusses the risk of retinal burns or flash blindness to friendly troops following nuclear weapon use. In order to understand this threat, one must have a fundamental understanding of how the eye reacts to extremely luminous objects, considerations for the environment and time of day, and thermal effects of nuclear weapons. Historically, this has been a heavily studied topic; however, previous studies have applied the question to pilots and aircrew operating at cruising altitude. Additionally, there are some counterintuitive aspects of the problem involving the inverse-square law applied to the weapon output and how yield influences the potential for eye injury. For planners, modelers, and subject matter experts, it is extremely important to understand the assumptions and technical aspects of the problem set in order to provide safe separation distances to servicemembers on the battlefield.