Need Backflow Preventer for 600 PSI Water Line

I am a bit puzzled by the application. Usually a backflow preventer is required by plumbing codes and used to protect a potable water supply from contamination. Potable water is seldom above 100 psi. The 600 psi water sounds like a special pumped system, which I would think could be isolated from the potable water with a plumbing code-compliant air gap. Rather than have the 600 psi system connected to the relatively low pressure domestic water supply, isolate the system with a tank and use a relatively simple 600 psi check valve to keep the flow in the right direction. Am I missing some detail?

A company named Sarco (you can easily Google their web site) manufactures a ide variety of flow control products for steam and the condensate water from it. They have units that can handle your pressure requirements.

When that thing spits, it's going to take somebody's eye out.