Water reuse in countries with drought and water shortage is necessary in order to provide sufficient water quantity for public, agricultural or private use. In addition to the use of rainwater, the usage of purified graywater is becoming increasingly important.
There are no standards in place in Europe for testing graywater plants. Countries such as the USA, Canada, the United Kingdom and Australia, on the other hand, have developed testing standards. Testing graywater plants offers the advantage that the manufacturer obtains a certificate which guarantees the quality of his product under normal conditions and under different stress conditions.
Testing graywater plants creates trust in the functional efficiency of the treatment technology and the quality of the treated water. In performance standards limit values are given depending on the end use. Authorities, designers and consumers are thus provided with an instrument enabling them to decide on suitable technologies.
It is important for graywater treatment systems to be tested by an independent third party that is authorized to perform such a test. In Europe, consideration is currently given to drawing up a testing standard for graywater plants. The question is whether existing standards are suitable for use in Europe. The contribution presents the American and Australian standards and discusses to what extent these standards are suitable for testing in Europe. This question will also be considered against the backdrop of the international marketing of graywater plants.