This presentation will focus on the various types of air valves used in the past and latter developments of air valves and their uses in mitigating water hammer and surge in pipelines. In addition the presentation will cover the engineering details involved in sizing and positioning of air valves for water, sewer, slurry/tailings and irrigation pipelines. There will be examples of some pipeline failures and successes relating to Ventomat air valves will be discussed.

The development of Ventomat air valve in South Africa involved an in depth study and testing in collaboration with the university. This new scientific approach led to new findings as to the behaviour of air valves and associated waterhammer events. This led to the development of the engineering for this innovative device. Mention will be made of the specialised materials that the Ventomat air valve is made which enables these devices to be used in arduous corrosive environments such as desalination plants.

Time will be spent discussing recent third party testing results regarding air flows that were carried out at Michigan University.