What is backflow?

• The sudden loss of pressure in pipework

• The normal direction of water flow

• The reversing of water flow

• The pressure of water downstream

What are the two types of backflow?

• Fluid categories and air gaps

• Back pressure and back syphonage

• Backflow and cross connection

• Contamination and water supply

Which method is the most effective for preventing contamination between water supplies?

• Type AD air gap with injector

• Type AA air gap

• Type AB air gap with weir overflow

• Type AG air gap with minimum size circular overflow

Which air gap is suitable for high risk situations and provides protection from insects, dust, and vermin?

• Type AA air gap

• Type AG air gap with minimum size circular overflow

• Type AB air gap with weir overflow

• Type AD air gap with injector

Which air gap is primarily used in commercial clothes washing machines and dishwashers?

• Type AA air gap

• Type AB air gap with weir overflow

• Type AD air gap with injector

• Type AG air gap with minimum size circular overflow

Which air gap is provided when cold water cisterns are installed correctly?

• Type AG air gap with minimum size circular overflow

• Type AD air gap with injector

• Type AB air gap with weir overflow

• Type AA air gap

Which air gap can be found on WC cistern and pan installations?

• AUK2 air gap for taps/combination fittings

• Type DC Pipe Interrupter with a permanent atmospheric vent

• AUK1 air gap with interposed cistern

• AUK3 air gap for taps/combination fittings

What is the gap located between the bottom of the outlet of a tap or other fitting discharging water over an appliance and the spill over level of the sanitary appliance?

• AUK1 air gap with interposed cistern

• AUK2 air gap for taps/combination fittings

• Type DC Pipe Interrupter with a permanent atmospheric vent

• AUK3 air gap for taps/combination fittings

Which air gap is present at kitchen sinks, through high neck pillar taps and monobloc mixer taps?

• AUK1 air gap with interposed cistern

• AUK2 air gap for taps/combination fittings

• AUK3 air gap for taps/combination fittings

• Type DC Pipe Interrupter with a permanent atmospheric vent

What is the non-mechanical fitting that prevents back syphonage by allowing air into the stream of back flowing water to break the syphonic action?

• Type DC Pipe Interrupter with a permanent atmospheric vent

• AUK3 air gap for taps/combination fittings

• AUK2 air gap for taps/combination fittings

• AUK1 air gap with interposed cistern