What are the preferred systems that are typically used to condition small to medium sized labs.I've read that terminal reheat CAV systems are preffered .Why is this?
It depends on a lot of specifics, but cost tends to be the biggest factor. CAV with terminal reheat systems are simple and less expensive than VAV or other more unusual types (chilled beam). But on larger systems, economies of scale help make the extra cost of VAV not as bad and the energy savings more attractive.