Wastewater characteristics
Wastewater has physical and chemical components, some of which may affect your selection of pipe materials or drainage system design.
Physical
Wastewater has physical characteristics such as temperature, solids, odour and colour. In plumbing work the temperature and type of solids in the wastewater are important considerations. Wastewater at high temperature will affect some piping materials and treatment units such as septic tanks. You may have to consider the use of an arrestor to pre-treat the wastewater.
Chemical
Wastewater contains chemicals such as nitrogen, phosphorus and levels of dissolved oxygen as well as others that may affect its composition and pH rating. Highly acidic or alkaline wastewater is probably trade waste and will require pre-treatment before discharge to the sewer.
The chemical properties of wastewater may also affect the pipe material. For example AS/NZS 3500.2 states that copper should not be used to carry undiluted urine from urinals or the discharge from grease arrestors.
Some establishments may also discharge toxic chemical substances in their wastewater, which will need pre-treatment.