Lasers can cause damage in biological tissues, both to the eye and to the skin, due to several mechanisms. Thermal damage, or burn, occurs when tissues are heated to the point where denaturation of proteins occurs. Another mechanism is photochemical damage, where light triggers chemical reactions in tissue.
March 9: Teams are allowed to begin negotiating with other teamsâ players who are set to become unrestricted free agents at the end of the league year. This is the first time the NFL is providing a window to negotiate with other teamsâ free agents prior to the start of free agency.
Undrafted free agents are players eligible for the NFL Draft but who are not selected; they can negotiate and sign with any team. Plan B free agency. Plan B free agency was a type of free agency that became active in the National Football League in February 1989 to 1992.