Triage is a system used by medical or emergency personnel to ration limited medical resources when the number of injured needing care exceeds the resources available to perform care so as to treat those patients in most need of treatment who are able to benefit first. The term comes from the French language word for sort. Two basic types exist: simple triage and advanced triage.
(From: http://en.wikipedia.org/wiki/Triage)

too many injured people need medical care, but we don’t have enough EMTs or ambulance. So, we need to build a rule to ”sort” injured.
first, if someone still have conscious even walking, then we will asign the color ”Green”; if he(or she) has no breathing, we will asign ”Black”; if he(or she) has useless breathing(<10/min or >30/min) or CRT>2 sec., we will asign ”Red”; if he(or she) was confuse and CRT<2 sec., we will asign ”Yellow”.

then we have to recheck the injured people to make sure his(or hers) status. because there is only one thing that the status won’t be better before hospital.

and the other thing is important that the radio-control. we can’t deliver injured to the same hospital, so we have to control the people. all in the same hospital just like that to move the accident to the hospital.