IRN R030

Multiple inlet fittings installed to protect against a backflow risk up to a Fluid Category 3, incorporating a self-cancelling diverter acceptable as a backflow prevention device (HC) and having an AUK2 or AUK3 air gap, shall be installed in accordance with IRN R010.  

Multiple inlet fittings installed to protect against a backflow risk up to a Fluid Category 5, shall be installed in accordance with IRN R010 and the shower hose shall be constrained as indicated in IRN R040. An AUK3 air gap must also be achieved at the spout outlet.