Appendix 1

Methodology to measure and calculate the average flush volume

1.   Test methods

Mount the flushing toilet or equipment following the assembling instructions delivered by the manufacturer. In the case of toilet receptacles, the equipment shall be mounted with a test flushing system, as described in relevant EN standards.

Install the mounted equipment on a firm flat horizontal or vertical surface as appropriate.

Connect the inlet valve to a water supply having a static water pressure of 0,2 ± 0,01 MPa (2 ± 0,1 bar) and open the water supply valve. Leave the water supply open during all the tests.

Operate the full flush mechanism control, collect the water delivered and discard it.

1.1.   Evaluation of the full flush volume

Operate the full flush mechanism control and collect the water delivered.

Measure the volume using a calibrated container.

Record the measured volume.

Perform the test three times.

If there are differences in the volumes delivered, calculate the full flush volume (Vf) as the arithmetic mean for the three recorded volumes.

1.2.   Evaluation of the reduced flush volume

Operate the reduced flush mechanism control and collect the water delivered.

Measure the volume using a calibrated container.

Record the measured volume.

Perform the test three times.

If there are differences in the volumes delivered, calculate the reduced flush volume (Vr) as the arithmetic mean for the three recorded volumes.

2.   Calculation of the average flush volume

Calculate the average flush volume (Va) as follows: