Cross Connection Control

There are three degrees of hazards that can result from cross connections;

  • Severe, involving any substance in sufficient concentration to cause death, spread disease or illness, or contain any substance which has a high probability of causing such effect.
  • Moderate, involving any substance which has a low probability of becoming a severe hazard and would constitute a nuisance or be aesthetically objectionable if introduced into the domestic water supply.
  • Minor, an existing connection, or a potential connection between the domestic water pipe and any pipe, vat or tank intended for carrying or holding potable water, which has a low probability of becoming a moderate hazard.

Followings are example of some installations that need protection.

Boiler Feed

  • The dangers of running a boiler dry are quite serious. This makes the installation of a valve that replaces any water that escapes or evaporates absolutely necessary.
  • This “boiler make-up valve” is connected directly to the building’s water supply. Previous generations of the plumbing code required a device to prevent this contaminated water from re-entering the potable system.
  • These previous generations stopped short of calling for a valve that we can prove works, and are called”non-testable backflow preventers”.
  • Backflow preventers are easily installed and give you the peace of mind of knowing that a licensed cross connections control technician will certify the device annually; and make sure that the building water is safe from contaminants leaving the boiler and fouling the building’s water.

Garden Hose

  • Hoses are the most common source of cross connection between potable water and contaminants.
    • Soap from washing the car
    • Hose end sprayers for fertilizer.
  • Can be fixed easily with a screw on vacuum breaker.

Filtration Systems

  • If the filter is not changed frequently, the filter can grow bacteria

Carbonated Beverage Tower

  • Soda machines with all that sugar can be a breeding ground for bacteria.

Fire Suppression System

  • Fire lines are connected to the water main and are filled with water when they are first put into service. These lines do not get replaced with fresh water except when there is a fire, and are then left to stagnate.

Irrigation System

  • Irrigation lines buried in the ground are depressurized and blown out in the winter to prevent them from freezing.
  • Bugs and other debris accumulate in the lines and are sometimes trapped in the system.
  • In the spring when the system is put back in service, there is a high possibility of contamination.