Air and Exhaust Gas Properties is an MS Windows application that calculates the properties of air/exhaust gases within a wide range of pressure and temperature. It may be used for analyzing a number of energy conversion units used in power plants and HVAC, such as gas turbines, compressors, boilers and heat exchangers. The accompanied help file "Thermodynamics online help" gives a brief description of these components. The results of the program can be transferred to the other Windows application, such as spreadsheets for further calculation. The user may choose the desired units for different input or output data. You may integrate Air & Exhaust Gas Properties into your application. A demo of DLL version of Air & Exhaust Gas Properties (air.dll 16-bit) is also included in the shareware package. Detailed instructions and sample file for MS EXCEL users included.