TGD H 2010 – 1.5.5.4 – SURFACE WATER DRAINAGE, Rainwater recovery systems

1.5.5.4 Precautions: To prevent contamination of the collected rainwater and the backup potable water supply and to prevent accidental ingestion, the system should: – (a) have pipe-work clearly marked in accordance with BS 8515: 2009 Rainwater harvesting systems – Code of practice and BS 1710: 1984 Specification for identification of pipelines and services, e.g. for rainwater green / black / green bands and the words RAINWATER in black lettering; (b) have external taps supplying rainwater clearly labelled and consideration should be given to having a removable handle (see Diagram 10); (c) have category 5 protection (an air gap, see I.S. EN 1717: 2000 Protection against pollution of potable water in water installations and general requirements of devices to prevent pollution by backflow) such as an AA type air gap conforming to I.S. EN 13076: 2003 Devices to prevent pollution by backflow of potable water – unrestricted air gap, or an AB type air gap conforming to I.S. EN 13077: 2008 Devices to prevent pollution by backflow of potable water – Air gap with non-circular overflow, fitted at the potable water top up point; (d) have a non-return valve fitted on the overflow; (e) have an anti-rodent device fitted to the overflow system; (f) have an automatic drainage system from the header tank, where used, in the event of stagnation.

C:BCARTGDTGD hTGD%20H%202010TGD%20H%202010%20-%20SECTION%201%201.5.5.4.pdf