Physical properties: Component Chemical name Molecular formula Weight% HC-290 Propane CH3CH2CH3 100%  Molecular weight  44.1  Boiling point  -42.2 C  Critical temperature  96.7C  Critical pressure  4250kPa (4.25MPa)  Odor  Slight ethereal  Form  Liquefied gas  Color  Clear, colorless  Specific heat of liquid at 25 C  1.64KJ/kgC  Absolute pressure at 25 C  0.95MPa      Vapor Density at 25 C(Air = 1)  1.5  Liquid Density at 25 C  0.492g/cm 3  Ozone Depletion Potential (ODP)  0  Global Warming Potential (GWP) 100yr  0.01  ASHARE Safety Group Classification  A3  Flammability at 1 atm. and 18 C  Extremely flammable Specifications: Purity(mol)%                             99.5 Water (v/v) %                            0.001 Total sulfur (ppm)                    1 Unsaturated hydrocarbon  %    0.01 Residue after evaporation %      0.01   R290 is a HC based refrigerant, which has zero ODP and a negligible GWP. It is replacement for R22 and R502 in low temperature refrigeration system.