vacuum breakerMaintaining water safety and quality in a home is an extremely important part of regular home maintenance and repairs. With the majority of households in the U.S. drinking tap water (71%), keeping impurities and contaminants out of the potable water supply is critical. While city water from the street is regularly inspected and treated by the municipal water authority, water inside a home can be contaminated by outside sources if not kept separate from outside impurities.

A common source of contamination in a home’s water supply comes through hose bibs through a process known as “backflow”. Water distribution networks are designed to have water flow in one direction towards its destination, however this can be disrupted by hydraulic conditions within the system. This can be caused by a garden hose turned on at the bib and closed at the end of the hose. Since the hose is fully pressurized, even a small drop in water pressure from the supply side can result in water being siphoned back into the household supply, contaminating it with impurities or chemicals.

hose bibb without vacuum breaker

Hose bibb without vacuum breaker

Two common pieces of hardware used to keep contaminated water from flowing into the water supply are vacuum breakers and backflow preventers. While vacuum breakers are a type of backflow preventer, these are often installed on older hose bibs whereas newer hose bibs typically have backflow preventers built into the bib. This can often be identified by a small hole in the stem of the hose bib handle.

While adding a full backflow preventer typically requires replacing the whole hose bib assembly, adding a vacuum breaker to a hose bib that does not have any backflow protection is a simple process. A hose bib vacuum breaker (HVB) is a simple device that screws straight onto the existing hose bib threads. The vacuum breaker allows water out during normal operation, but in the event of sudden pressure reversal, opens and vents to the atmosphere. This prevents water from reversing up the hose bib and into the water supply.

Vacuum breakers and backflow preventers are important safety features that are critical in protecting the water inside your home and keeping contaminants out of your drinking water. As these are relatively inexpensive and very easy to install, installing a vacuum breaker on your hose bib if it does not already have a backflow preventer is one of the easiest ways to help protect yourself and your home.