I too am a firefighter/paramedic and have been leery when thinking about purchasing the S7 Edge purely based on its design. However, thinking back, I have only ever broken the screen on one phone and it was because I dropped it while I had its case off for a moment. I typically carry my phone in my pocket with the screen facing inward against my leg so that external bumps/hits would not impact the screen directly through my pants. If I can help it, I typically take my phone out of my pocket prior to donning my turnout gear and it simply stays on the truck or back at the firehouse.
That being said, Spigen makes several cases that extend out slightly beyond the edges of the curved edge just enough to hopefully protect it during a drop. Same for several other companies: Otterbox, Verus, etc.
As well as the Edge designs have sold in the past couple years with the S6E and Edge +, it seems that increased susceptibility to breakage would have shown its face by this point. After talking to several Best Buy, T-Mobile, and Verizon reps, it doesn't seem that the design is overly fragile if handled in an appropriate way with a case on it.