What are your thoughts on them? In civilian E.M.S. / P.H.T.L.S. they are big. In real life (civilian or military) what to you guys do. Note: In civ. EMS we are trained and I have performed a few chest decomps. I have been reading from journals that it is of little to no value and that it was invented for the lay person back in the day. I know about the size of ther injury rule v/s. the diameter of the trachea thing. Thoughts? F.M.