This manual is an engineering and operations guide for selecting, sizing, locating, and installing air valves in drinking water supply applications. It provides a basic understanding of, and recommended practices in, the use of water supply air valves. The manual covers types of air valves and suggested installation locations along a pipeline, as well as a method for selecting the correct valve orifice size depending on usage. Water hammer conditions, installation considerations, operation and safety issues, and maintenance are also described.