Cross Connection Control
Frequently Asked Questions
What is a cross connection?
A cross connection is a direct arrangement of a piping line which allows the potable water supply to be connected to a line which contains a contaminant. An example is the common garden hose attached to a hose bib with the end of the hose lying in a cesspool. Other examples are a garden hose attached to a service sink with the end of the hose submerged in a tub full of detergent, supply lines connected to bottom-fed tanks and supply lines to boilers.
What is a cross connection control program?
This is a combined cooperative effort between plumbing and health officials, water purveyors, property owners and certified testers to establish and administer guidelines for controlling cross connections and implementing means to ensure their enforcement so that the public potable water supply will be protected both in the city main and within buildings. The elements of a program define the type of protection required and responsibility for the administration and enforcement.
What is the most common form of a cross connection?
Ironically, the ordinary garden hose is the most common offender as it can be easily connected to the potable water supply and used for a variety of potentially dangerous applications.
What are the typical cross connections found in a residential home?
Outdoors: The most common example in a home environment is a garden hose attached to an outside tap or hose bib with the end of the hose connected to a pesticide sprayer or left submerged in an ornamental pool; underground lawn watering (irrigation) systems.
Indoor Fixtures: Laundry sink c/w hose, handheld shower heads immersed in water, alternative heating systems and auxillary water sources.
Other: Boilers, fire protection systems and in-home water treatment (softeners) systems, high pressure washer, etc.
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System without an Air Gap |
System with an Air Gap |
What is an Air Gap?
Air Gap is the physical separation of the potable and non-potable system by an air space. The vertical distance between the supply pipe an the flood level rim should be two times the diameter of the supply pipe but never less than 1”. The air gap can be used on a direct or inlet connection and for all toxic substances.
Will a cross connection control device affect my water pressure?
Yes, essentially all cross connection control devices cause some degree of pressure loss. The typical pressure drop across a device depends on the type, make, size and location of the device. Refer to the manufacturers literature.
What is back-siphonage?
Back-siphonage is the reversal of normal flow in a system caused by negative pressure (vacuum or partial vacuum) in the supply piping.
What factors can cause back-siphonage?
Back-siphonge can be created when there is stoppage of the water supply due to nearby fire-fighting, repairs or breaks in city mains, etc. The effect is similar to the sipping of an ice cream soda by inhaling through a straw, which induces a flow in the opposite direction.
What is backpressure-backflow?
Backpressure is the reversal of normal flow in a system due to an increase in the downstream pressure above that of the supply pressure.
What factors can cause a backpressure-backflow condition?
Backpressure-backflow is created when the downstream pressure exceeds the supply pressure which is possible in installations such as heating systems, elevated tanks and pressure-producing systems. An example would be a hot water space heating boiler operating under 15-20 lbs. pressure coincidental with a reduction of the city water supply below such pressure (or higher in most commercial boilers). As water tends to flow in the direction of least resistance, a backpressure-backflow condition would be created and the contaminated boiler water would flow into the potable water supply.
What is the difference between pollution and contamination?
Pollution of the water supply does not constitute an actual health hazard, although the quality of the water is impaired with respect to taste, odour or utility. Contamination of the water supply, however, does constitute an actual health hazard; the consumer being subjected to potentially lethal water borne disease or illness.
What are the five basic products used for protection of cross connections?
- Air Gap
- Atmospheric Vacuum Breakers – which also includes hose connection vacuum breakers
- Pressure Vacuum Breakers – which also includes a backflow preventer with intermediate atmospheric vent for ½" and ¾" lines
- Double Check Valve Assembly
- Reduced Pressure Zone Backflow Preventers
I have received a letter stating that appropriate cross connection control assemblies must be installed to comply with the City of Kelowna Bylaw 8147 Sec 30. What am I required to do on my property?
Contract a Certified Tester (i.e. journeyman plumber, mechanical contractor) to install the cross connection control on the identified water supplies.
Why do cross connection control devices have to be tested periodically?
Cross connection control devices have internal seals, springs and moving parts that are subject to fouling, wear or fatigue. Therefore, all cross connection control devices have to be tested periodically to ensure that they are functioning properly.
I have received a letter stating that my cross connection control devices are due for testing. What am I required to do?
Contract a Certified Tester (i.e. journeyman plumber, mechanical contractor) to install test and submit the test report(s) to the water purveyor and you should also receive a copy of the report.
Who is responsible for testing a cross connection control device?
Generally, it is the owner of the property or agent of the owner (i.e. property manager) or as identified in the lease agreement. If the cross connection control device belongs to the tenant then the tenant should be responsible.
Can a time extension be granted to arrange for the installation or testing of a cross connection control device?
Yes, however each request must be presented in writing to the Cross Connection Control Officer and will be individually assessed due to the factors involved (i.e. degree of hazard, type of protection etc.).