The flash point of any heat transfer liquid used in solar system equipment and appliances shall not be less than the highest temperature as determined from the following:
1. Fifty degrees (28°C) above the design maximum operating (flow) temperature of the fluid in the solar system.
2. Two hundred degrees (111°C) below the design maximum non-operating (no-flow) temperature of the fluid attained in the collector, if the collector manifold assembly is located outside of the building and is exposed to the weather, and the relief valves located adjacent to the collector or collector manifold do not discharge directly into the building.
3. The design maximum no-flow temperature in other collector manifold and relief valve configurations.