I just learned this from my latest Android update.
At any time and within earshot, you can say, OK Google call, a name in your contacts and I suspect it works for 911 if you need it. Just in case you're alone and can't reach your phone.
Mine says it won't do emergency calls. I put the local number of the police station into Contacts and I trust that will work. I don't want to call the cops just to test it! I must do likewise for the hospital.
Same here. I hear the 911 operators don't like test calls either but you can call a friend, I did try that with my phone about 5 feet away and that worked.