Updated plumbing and drainage standards - Part 1: Water services

(Update to clause)

The standards below are now called up in the normative references as referenced by various clauses, and must be complied with.

• AS 1397, Continuous hot-dip metallic coated steel sheet and strip – Coatings of zinc and zinc alloyed with aluminium and magnesium
• AS 1432, Copper tubes for plumbing, gasfitting and drainage applications
• AS 3688, Water supply and gas systems – Metallic fittings and end connectors
• AS 3735, Concrete structures for retaining liquids
• AS/NZS 1546.1, On-site domestic wastewater treatment units, Part 1: Septic tanks
• AS/NZS 4020, Testing of products for use in contact with drinking water
• AS/NZS 4129, Fittings for polyethylene (PE) pipes for pressure applications
• AS/NZS 4766, Rotationally moulded buried, partially buried and non-buried storage tanks for water and chemicals

(Update to clause)

• This change accommodates the different pipe description methods – some 100 mm pipes are referred to by internal, nominal, or external diameter. As a result, 110 mm has now been included instead of 100 mm.
• The pipe size range has changed, as follows:
  • For allowable operating pressure of at least 1,200 kPa at 20° C, the pipe size range has increased from ≤ 100 mm to ≤ 110 mm.
  • Pipes larger than 110 mm must be selected to suit the operating pressure and temperature for the system.
• Explanatory note added: Provided it does not contradict the requirements of this standard, limitations on the use of pipes and fittings should include the manufacturer’s installation specifications and scope of use.
• Explanatory note added: Installation method of pipes and fittings should avoid exposing pipes and fittings to excessive ambient heat or to excessive heat from a device or appliance.

(Re-numbering of clause)

Requirements regarding flexible hoses have been relocated to this clause (previously in Clause 2.3(c) of the 2021 edition).

The requirements have not changed.

(New clause and new table)

• Flexible hose assemblies are categorised into four different classes based on their application, as follows:
  • Class 1 are end of line flexible hoses with an open end (i.e. no isolation device after the inlet of the hose). Class 1 must only be used for dynamic pressure applications (i.e. must not be used for static pressure applications).
  • Classes 2 or 3 are flexible hoses used to connect between fixed points. Classes 2 or 3 are used for static pressure applications.(Note: fixed points are either between rigid supply lines and a fixture, fitting, valve, tap, appliance or similar; or fixed points are between supply line to supply line to allow for expansion or movement.)
  • Class 4 are end of line flexible hoses with an integral stop valve or trigger. Class 4 are used for static pressure applications.
• Flexible hose assemblies must meet the requirements in Table 2.3.2.2. Plumbing practitioners need to know the maximum operating pressure and maximum hose length that relates to each class of flexible hose.

The requirements are summarised in the table below.

• Max operating pressure:
  < 250 kPa
  (for use under dynamic pressure).
• Max length: 10 m

• Max operating pressure:
  1,400 kPa  
  (for use under static pressure).
• Max length: 2 m

• Max operating pressure:
  25 mm = 1,400 kPa32 mm = 1,350 kPa
  (for use under static pressure).

• Max length: 10 m

• Max operating pressure:
  1,400 kPa  
  (for use under static pressure).
• Max length: 10 m for < 25 mm
  2 m for ≥ 25 mm

(New clauses)

Plumbing practitioners must use the flexible hose suited to the application. The marking on the flexible hose specifies the suitable application.

Rated to this temperature and hoses marked with “70° C” or “L”

or

Hoses marked with “90° C” or “H”

(New clause)

• Semi-flexible hoses must:
  • only be used in accessible locations
  • not be buried
  • not be used where repeated movement is expected.
• Explanatory note: semi-flexible hoses are commonly called ‘semi-rigid hoses.’
• Examples of installations of semi-flexible hoses include connections of appliances, tapware, water heaters, expansion joints, seismic joints, or offset connectors.

(Update to clauses)

• Atmospheric vacuum breakers (AVB) have been reclassified from “non-testable devices” (2021 edition) to “registered testable devices” in the 2025 edition (see Table 4.4.1).
  • There is no change to the hazard rating for AVB – AVBs can be used for high, medium or low applications.
• Explanatory note added: Field testing and maintenance procedures for backflow prevention devices are specified in AS 2845.3.

(Update to clause)

• In the 2025 edition, atmospheric vacuum breakers (AVBs) are testable backflow prevention devices that must be commissioned and tested as specified in AS/NZS 2845.3.
• AVBs must only be
• used in conjunction with a maintenance program for device registration and test certification.

(Update to clause)

• Except for fire services, AVBs must be fitted with line strainers.
• Explanatory note: AVBs should not be installed with downstream isolating valves.

(Update to clause)

If backflow prevention devices are fitted with test taps, or if dismantling of backflow prevention devices is required for testing; the location of the device needs to enable the test procedure or maintenance to be performed.

(Update to clauses)

Atmospheric vacuum breakers (AVB) installation requirements have been relocated from “non-testable devices (clause 4.6.3.3 in the 2021 edition)” to “testable devices (clause 4.6.3.2) in the 2025 edition”.

The requirements for the installation of AVBs have not changed.

(Update to clause)

Isolation valves must be installed immediately before each flexible hose assembly that is connected to a mixer valve, tape outlet or cistern.

(New clause)

• Devices and appliances connected to the drinking water supply must meet the requirements below.
  • Pipework and fittings must be sized to provide adequate water supply to the device or appliance as specified in Section 3.
  • A backflow protection device must be installed as specified in Section 4.
  • An isolation valve shall be installed as specified in Clause 5.4.
  • If a lower pressure is required to prevent damage to the device or appliance, a pressure limiting or reducing device must be installed. Refer to product specifications for pressure requirements.
  • Pipework and fittings must enable the disconnection and maintenance of devices or appliances.
• Explanatory note: See Appendix B of this standard for information regarding demonstrating that products and materials are fit for purpose.

(Update to clause)

Explanatory note added: Plumbing practitioners need to consult the network utility operator, because the network utility operator may require the non-drinking water meter assembly to be in a different location to Figure 9.1.