EMTs arriving on scene are legally bound to start resuscitation because there is no DNR order
7 minute mark
While the current NAEMSP guidelines do not endorse any set time for EMS to perform resuscitation at the scene, Both the previous NAEMSP guidelines and the current European Resuscitation Council recommend 20 minutes of on-scene efforts before terminating efforts.[26][27] This recommendation has led to many departments implementing rules for termination of resuscitation that include providing at least 20 minutes of on-scene CPR.[28] Also, EMS agencies must have active physician oversight when making protocols and must take into account the training of the providers.