Australian Standards AS/NZS 1546.1 and AS 1546.3

The release of the Australian Standard AS 1546.3:2017 “On-site domestic wastewater treatment units – Part 3: Secondary treatment systems” superseded the version AS 1546.3:2008. The current standard AS 1546.3:2017 stipulates requirements regarding the design, commissioning, performance and the compliance testing of decentralized wastewater treatment systems designed to treat domestic wastewater. As a complement to this, guidance is provided on installation, operation and maintenance. In addition, the standard stipulates test methods for systems with a treatment capacity ranging from 1,200 l/d to 5,000 l/d.

After an initial phase, the plants have to be tested under alternating load conditions for at least 34 weeks. Every model of a series must be tested individually, theoretical approaches for the evaluation of a series are not allowed. There is a total of 4 classes for the classification of wastewater treatment plants, for which the standard specifies criteria on the effluent quality.

Apart from testing the wastewater treatment plants in accordance with AS 1546.3:2017, the tanks have to comply with the requirements laid down in standard AS/NZS 1546.1:2008, “On-site domestic wastewater treatment units – Part 1: Septic tanks” regarding the hydraulic design, the material and the structural stability.

PIA GmbH as a laboratory accredited according to ISO 17025 conducts all tests required in compliance with the requirements of the Australian standard. PIA GmbH is cooperating with SAI Global,  one of the Australian Conformity Assessment Bodies (CAB), granting the certification required for the Australian market after passing the tests successfully.

At present, there are about 30 manufacturers involved in the field of decentralized wastewater treatment systems in Australia. The Government of South Australia states that at the end of 2020, the manufacturers must have their plants tested in accordance with the new Australian standard, otherwise it will no longer be possible to sell such systems on the South Australian market.