Bernie, might want to check closer. The Volunteer FD I'm in only uses some type of food based oil in their Hurst extracation equipment. I can't remember if it is non-flammable. I know it costs way more than regular hyd oil. I do know it is non-toxic.
Hurst (as in the brand name, 5000 PSI) fluid is Phosphorous Ester. Blue, looks like windshield washer fluid in the gallon jug. About $100 a gallon. Is is most certainly not food based. It is a corrosive fluid that is an irritating to the skin. It will give you rash or a chemical burn from exposure to it. However, it is not flammable, and that is how it was originally marketed.
Rescue Tools (not Hurst 500 PSI, but all others at 10,000 PSI) are mineral oil based. It looks like motor oil, maybe a little lighter, and is in the $30 a gallon range (much less in bulk). Some sales pitches for mineral oil based rescue fluids have pointed out that mineral oil is a food product, but truth be told in the form we use it it is not. It is however much safer for the firefighters, as it isn't corrosive or an irritant. In my option, it is a better option than Hurst brand fluid.
For years, Hurst has pushed the "safety" of their fluid because it isn't flammable. Honestly, I think it is a moot point. Crashed cars are filled with fuel, and ignition sources. The oil in a sealed hydraulic rescue tool system is the least of a firefighter's worries. The rescue tool oil only pose a threat if you had an open flame, and a rescue tool leak just right so the mineral oil could atomize under pressure. If you have an open flame, you have bigger problems than your rescue tools.
Full Disclosure: My company sells and services the mineral oil based tools, and has hundreds of gallons a year that we dispose of. Just an idea if that could be 100 gallons of free fuel.