Defining "Self Defence" rule for Workers (Firefighter and Medic)

Defining what "self defense" is in /medicrules would be great as it's quite vague. Make it clear as day that you can ONLY shoot and/or kill a player when they inflict SOME damage which should be visible in /actions, and you CANNOT shoot or engage in combat if they aim at you, if they're visible as a threat to you, or shoot at you but miss completely. This would save the staff from debating whether to award a PSO or not, and also the players from getting a PSO. Hope this is considered for the betterment of MCNR and its players.