One of the first questions anyone new to SAR asks is "What should I carry in my pack?"
There is no set answer to that question since every callout is different in nature from the rest.
Some SAR team's policy on Rescue packs has been to sustain the rescuer for 24 hours in the field without resupply.
It sounds simple, but what if you find the victim (something we all want to find) & he's not equipped & has hypothermia? What happens now is that you must take care of the victim out of your pack until help arrives with extra gear. Obviously, you might not be able to do a very good job caring for the victim with just a fanny pack.
Rescuers are depended on to carry the proper equipment to be effective as well as keep up with the other rescuers.