The subject of water hammer has been kicked around here as of late. I, for one, would be interested in some photos of damage that can be directly attributed to water hammer. With them, could go the information on the static pressure, and length of supply line leading to the valve that did the hammering. For myself, I can contribute little. I've never had upstream plumbing damaged from water hammer. The only upstream event I can recall involved a customer wanting me to reuse all the original system components, including an Orbit master valve (first time I ever dealt with one of them) - said Orbit valve blew off the 1-inch copper male adapter less than a week after the renovation. 100 psi static pressure, and less than 80 feet from street to master valve. A Richdel 205F took its place, and no more was ever heard from the master valve.