Hello and welcome everybody to today's session regarding the key changes in the 2025 edition of AS 3500 Series Part 2, Sanitary Plumbing and Drainage.
A few of the major changes are new requirements for the installation of waterless urinals, new provisions for the connection of miscellaneous devices and appliances to a sanitary drainage system.
There are also updated requirements for the main drain lines of a sanitary drainage system serving multi-unit developments.
Polypropylene pipes and fittings have now been included as an alternative material and product for vacuum drainage systems and there are also editorial changes that make this standard much easier to read.
Firstly, clause 1.1 now has been updated where the informative note from the previous standard has now been incorporated into the 2025 standards.
Plumbers should now coordinate with the Network Utility Operator regarding the requirements for pretreatment of trade wastes.
Clause 13.21 has now been updated to allow a tundish to be connected to a disconnector gully.
Tundishes must also be accessible and securely fixed to prevent movement.
There are new guidelines that have been introduced for the installation of waterless urinals.
Please note that where a room contains one or more wall hung urinals, the floor must be graded in accordance with the requirements set out in Volume One of the National Construction Code.
This means that the plumbers should coordinate with their builder regarding these requirements.
In this new clause here, it states that waterless wall hung urinals must be connected directly to a soil stack, common discharge pipe or drain.
A new figure has been introduced illustrating the connection of waterless urinals installed on grade to drains located outside the building or in a service duct from the side view.
This new clause has been added to outline the requirements that fixture discharge pipes from waterless urinals must comply with, as you can see here.
This new figure illustrates the connection of waterless urinals on grade to common discharge pipes where you can see the 20° minimum and 45° maximum incline to the horizontal drain.
This new figure shows the individual discharge pipe not inclined at more than 45° from the vertical.
This is a new clause that has been added to the standard which outlines the connection requirements that waterless urinals must comply with when connecting to common discharge pipes.
There are 5 new requirements.
These are 45° Junctions shall be used to connect individual discharge pipes to drains.
Common discharge pipes shall be no less than 65 millimetres.
Common discharge pipes shall have wastewater equivalent to 1 fixture unit discharge for each waterless urinal connected to the common discharge pipe upstream of waterless urinals.
If the requirements of Item C cannot be met, an approved flushing device shall be installed upstream of waterless urinals.
Common discharge pipes shall not be smaller than 100 millimetres when toilets are connected upstream.
A new figure has been added to the standard showing the connection of waterless urinals with 45° top entry junction to drains.
Another new figure has also been added to the standard illustrating the connection of waterless urinals, this time with a 45° top entry to common discharge pipes.
This is another new figure, although this time, it is illustrating an alternative connection of waterless urinals with 45° top entry to common discharge pipes.
A new figure has been added to the standard illustrating the connection of fixtures upstream of waterless urinals.
Keep in mind this figure does not show venting requirements.
This new clause has been introduced to the standard to outline the requirements for inspection openings on waterless urinals.
These include provisions for both individual and common discharge pipes.
The clause regarding the conversion to waterless urinals now has an update.
It now clearly states that urinals must not be converted to waterless urinals nor replaced with waterless urinals, unless the requirements of clauses 13.24.2.1 and 13.24.2.3 have both been met.
A new clause has been added to the standard outlining the requirements for the connection of miscellaneous devices and appliances to a sanitary drain.
Now, a miscellaneous device is any appliance or device that is not actually listed in Section 13 and connected to a sanitary drain.
An example of this miscellaneous device could be a coffee machine.
This new clause “Connections to the Sanitary System”, has been introduced.
It specifies that discharge must enter the sanitary system either through a direct connection to a dedicated trap or via tundish.
Now this clause “Intermittent Discharge” has been added to outline 3 requirements for cases where a device does not discharge frequently enough to maintain a trap seal.
These updated requirements are now displayed on screen.
There are also new requirements regarding large volume discharge.
This clause states that the sanitary system must be appropriately sized for the expected discharge volume and include a trap with a water seal of at least 100 millimetres matching the size of the discharge pipe.
Continuing on with large volume discharge, it is also a requirement that venting must be provided for the sanitary drain in addition to any other existing venting requirements, as specified in Section 6 of the standard.
Clause 14.2.1 has been updated to mandate that multi-unit developments must include inspection shafts, open upstream vents and overflow relief gullies.
This new figure illustrates a typical sanitary drain for multi-unit developments as specified in the previous slide.
Another new figure has been introduced to illustrate the maintenance shaft used in multi-unit developments.
This figure indicates that the shaft must provide ready access at ground level for drain clearing equipment and CCTV inspections, include a vertical riser with a diameter of no more than 300 millimetres, and be fitted with a sealed riser cap and an access cover.
Clause 16.2 now has an update where polypropylene pipes and fittings are included as an alternative material and product for vacuum drainage systems.
And that concludes the key updates to the 2025 edition of AS 3500 Part 2.
If you require further information or you have any more questions, please don't hesitate to email us at plumbingtechnicaladvice@bpc.vic.gov.au.