situation requiring an arterial  tourniquet:
 an arterial tourniquet should be used as a last-resort to stop bleeding,only after the following methods have filed:
1.direct pressure.
. manual;
. first pressure dressing;
. second pressure dressing;
. inflatable splint;
. anti-shock trousers;
2.elevating the injured limb.
3.splinting the injured limb.
4.pressure point control.