GMJ 9189 phase 3 cold water MCQ

How can the cold water supply pressure to a property be identified?

• By contacting the local council or using a weir gauge at the kitchen sink

• By contacting the local council or using a pressure gauge at the supply to the FOV

• By contacting the water undertaker or using a pressure gauge at the cistern-fed outlets

• By contacting the water undertaker or using a pressure gauge at the kitchen sink

Which formula can be used to determine flow rates through a pipe?

• Q = Av

• Q = A-v

• Q = m/s

• Q = V2

What term is given to the length of pipe when all fittings and components are considered during pipe sizing?

• Equivalent length

• Actual length

• Mean length

• Velocity length

Which of the following is not a source of information that should be consulted to assist in pipe sizing for cold water systems?

• BS EN 806 -2: 2012

• BS EN 806-3: 2012

• BS 8558: 2015

• BS 4213: 2004

According to guidance, all pipes and joints of a cold water system should be designed for a service life of:

• 25 years at a temperature of 20C and a design pressure of 15 bar

• 50 years at a temperature of 20C and a design pressure of 10 bar

• 25 years at a temperature of 25C and a design pressure of 10 bar

• 50 years at a temperature of 25C and a design pressure of 5 bar

What is the recommended storage capacity of a CWSC supplying cold and hot water to a house?

• 100 litres minimum

• 150 litres minimum

• 230 litres minimum

• 350 litres minimum

What is the recommended flow velocity of cold water within pipework?

• Between 0.25m/s and 1.5m/s

• Between 0.5m/s and 2m/s

• As close as practically possible to 2.5m/s

• As close as practically possible to 3.5m/s

Which of the following factors would not directly affect the pressure and flow rates of pipework?

• Pipe diameter

• Pipe material

• Number of bends

• pH level of the water supply

A cistern measures 900mm x 900mm x 800mm and has a working capacity of 70% when filled to its shut-off level. How much water does it store?

• 260 litres

• 453 litres

• 648 litres

• 722 litres

A pump is required to lift water to a storage cistern at height. A delivery rate of 5kg/s is required and the total length of pipework (including pipe valves and fittings) is 40m. Given a pump efficiency of 75%, what is the required power of the pump in watts?

• 1,765 watts

• 1,962 watts

• 2,609 watts

• 2,995 watts