Compressed Natural Gas and Liquified Natural Gas facilitates have unique requirements. When you are running a CNG fleet of vehicles, your maintenance shops cant be heated by conventional means. The CoRayVac SF is the solution! It provides energy efficient comfort while meeting the NFPA 30A 7.6.6 standard. Available with 40M BTU, 60M BTU, and 80M BTU burners.The only way to heat facilities with CNG vehicles efficiently and comfortably, while meeting NFPA safety standards.