ESDU 79037 gives information to assist the specialist and non-specialist in fan selection and tender appraisal. For the non-specialist@ the special terminology appropriate to fans is introduced@ the types of fan available and their typical performance characteristics are reviewed@ the requirements of a system are outlined in terms of stability@ flexibility@ growth potential@ need for stand-by@ and other factors@ and the choice of a fan to match those requirements explained. Then@ for specialist and non-specialist@ a selection procedure is developed that enables the impeller power@ speeds and maximum dimensions for a given duty to be estimated. A method of predicting the sound power spectra generated is also given@ together with general guidance on the presentation and use of noise data. The specification of electric motors for fans is considered@ covering the characteristics of the various types and those features of particular relevance to the application. A practical worked example illustrates the use of the procedures.