Chapter 5: Pipe Sizing

What is the recommended design flow rate for a WC flushing cistern single or dual flush to fill in 2 minutes?

• 6 liters per minute

• 4 liters per minute

• 8 liters per minute

• 10 liters per minute

According to BS 6700, what is the maximum flow velocity that should not be exceeded?

• The maximum flow velocity that should not be exceeded according to BS 6700 is typically 2 m/s.

• The maximum flow velocity that should not be exceeded according to BS 6700 is typically 1 m/s.

• The maximum flow velocity that should not be exceeded according to BS 6700 is typically 3 m/s.

• The maximum flow velocity that should not be exceeded according to BS 6700 is typically 4 m/s.

Which of the following is the design flow rate for a bath tap, nominal size 3/4 – DN 20?

• 0.20 l/s

• 0.30 l/s

• 0.60 l/s

• 0.15 l/s

True or False: Loading units should not be used for outlet fittings having high peak demands in industrial installations.

• True

• False

Explain the importance of sizing pipes and fittings according to the design flow rates.

• To ensure efficient water flow and prevent pressure loss

• To increase the cost of the plumbing system

• To make the installation process more complex

• To reduce the lifespan of the plumbing system

What are the consequences of oversizing pipes according to the text?

• Increased cost and reduced efficiency

• Improved water flow and pressure

• No significant impact

• Reduced maintenance requirements

List the potential issues caused by undersizing pipes as mentioned in the text.

• Increased pressure drop and energy consumption

• Reduced water flow and efficiency

• Higher risk of pipe damage and leaks

• All of the above

According to the diagram, what does 'available head' refer to?

• The height of water above the turbine

• The pressure of water in the system

• The flow rate of water through the system

• The efficiency of the turbine

In smaller installations, pipes are typically sized by:

• diameter

• length

• material

• pressure

The recommended method for pipe sizing in larger and more complex buildings is:

• using empirical methods

• using computer simulations

• using standard tables

• using detailed calculations