Page 20 - ebook

Cross Connections
“Safe Drinking Water”?
Testing and Commissioning of Non-drinking Water Systems
Testing and reporting requirements are essential to ensure the correct installation and operation of non-drinking water systems. AS/NZS 3500 sets out clear requirements for the testing of all non- drinking water plumbing installations.
All non-drinking water installations including those within a Class 1a building are to be tested in accordance with AS/NZS 3500.11, and require a cross connection test to be conducted. The procedure for conducting the cross connection test for Class 1a buildings is detailed in Table 2-2.
Table 2-2 Cross connection test procedure for Class 1a buildings
CLASS 1a FOR CROSS CONNECTION TEST PROCEDURE
TASK
DESCRIPTION
1.
Check that the non-drinking water supply to the property is turned off at the meter (or the isolating valve if looped to the drinking water supply), check that the drinking water supply is turned on at the meter (or by isolating the valve downstream of the loop).
2.
Turn on all hot and cold tapware including appliances (one by one). All tap outlets including appliances are to be operational.
3.
Flush all toilets. The toilets will not fill provided they are connected to the non- drinking water service. The inlet for the toilet shall be clearly identified with appropriate warning/prohibition signs.
4.
Turn on all outside taps. Taps that continue to run are connected to the drinking water service and taps that run dry are connected to the non-drinking water service. All external hose tap outlets connected to the non-drinking water shall be coloured purple, have removable handles and shall be clearly marked with appropriate warning/prohibition signs.
5.
Turn off the drinking water supply at the meter (or isolating valve downstream of the loop) and turn on the non-drinking water supply at the meter (or isolating valve if looped to the drinking water supply).
6.
Turn on all hot and cold tapware including appliances (one by one). All tap outlets including appliances are to be non- operational.
7.
Flush all toilets, the toilets should now fill.
8.
Turn on all outside taps, the drinking water taps will run dry and the non-drinking water taps will be operational.
9.
Turn on the drinking water meter slowly and turn on the tap connected to the drinking water service that is located furthest away from the meter so that all the air will purge from the pipeline while it is being charged.
A cross connection test must be conducted by the appropriately licensed person who installs the pipework on the property.
An additional cross connection test must also be carried out by an appropriately licensed person in conjunction with the water industry entity or water supplier who supplies the non-drinking water. This occurs when the non-drinking water service is activated. The results of this cross connection test must be retained by the water industry entity or water supplier.
The cross-connection test shall be conducted at the isolation valves located adjacent to the drinking and non-drinking water services.
Figure 2-6 Examples of connection between non-drinking water and drinking water services
1 Copied by the SA Office of the Technical Regulator with the permission of Standards Australia under Licence 1606-c139 18