Refrigerant mixtures are likely replacements for several of the CFC and HCFC refrigerants, particularly R22 and R502. Accurate transport properties are needed for the design of equipment using refrigerant blends; the transport properties are particularly important for the design of the condenser and evaporator.Transport property data for some of newly commercialized refrigerant mixtures are now available in the literature. But there is no comprehensive mixture model for the transport properties. A suitable comprehensive model would allow data at compositions differing from the commercial blends and even data on different, but chemically similar mixtures, to be used to supplement the data available for a particular blend, allowing extrapolation to higher or lower temperatures or pressures.The objective of this work is to carry out a literature survey and evaluate the available transport property (viscosity and thermal conductivity) data for refrigerant blends, in both the liquid and vapor phases; use these data to develop a comprehensive model for the transport properties of refrigerant blends, and use this model to produce data tables for R404A, R407C, R410A, and R507A.