Chapter 6 of 125% of exam
Mechanical & Plumbing
Mechanical and plumbing (6 of 115 items) covers the rough-in and protection of building systems the general contractor coordinates. This chapter reviews cross-connection control.
Backflow and cross-connection control
Where a potable water system connects to a non-potable system, such as irrigation, a backflow preventer stops contaminated water from being siphoned or pushed back into the drinking-water supply when pressure drops or reverses. Plumbing codes require backflow protection at cross-connections. The general contractor coordinates these mechanical and plumbing rough-ins with the structural and finish trades to avoid conflicts.