The complexity of working in an OSHPD regulated hospital environment requires a contractor with great technical skill, and organized management capabilities. In 2008/2009 Preston worked at USF General Hospital, El Camino Hospital Mountain View, Stanford Main Hospital, Lucille Packard Children’s Hospital, Washington Hospital in Fremont, Mills Peninsula Hospital, Kaiser Santa Clara, Kaiser Pinole, Queen of the Valley Medical Center in Napa, John Muir Medical Center in Concord, Sutter Medical Center Sacramento, and Catholic Healthcare West Sacramento.