Adding underbelly weather protection, is it safe?

JMO, but the main steel propane line, would not likely be a leak risk, but more likely the area of appliance connections. That being said, the steel pipe for propane line is on the outside of the coroplast cover under my FW. I have the reflectix insulation laying above the coroplast, and another layer of reflectix attached to all floor bottoms. It seems to insulate well, would be easy to install, plus the waterproof benefit.

Jerry