One of my former employers had an internal first responder group, and as a part of that I was able to get and maintain first-aid, CPR, AED, BLS/Airway certifications over several years. My current employer doesn't. I still have a really nice kit I got from Galls, and I still keep it refreshed as needed. I'd love to keep an AED in the truck, and we have plans to add one in the next couple of years, especially as some of the places we go are WAY out in the middle of no-where (no cell service, no EMS within 100 miles or more).
There is almost always an ARC office somewhere nearby where you can find and take classes. I highly recommend them. When time permits, I plan on re-certifying.
I do have an Extra-class ham radio license, and with the gear I have I can communicate locally either direct or via repeaters (many of which include telephone autopatch to get to 911) and all the way around the world. I have participated with local emergency communications groups and SAR groups, and through them have training and experience guiding in life-flight and others.