The National Federation of High School (NFHS) has alerted its members that concussion-related litigation is gathering momentum, and is increasingly targeting coaches and school officials at the high school level (Koester). The Impact Indicator identified potential injuries, and helped coaches and players avoid a subsequent collision to an already injured brain. A light on the chin strap shines green until a player is struck in such a way that a head injury is either possible (yellow light) or likely (red light). A coach who spotted the yellow or red light might then sideline the injured player.