Question 5
(5) (a) Define the term water hammer.
(b) (i) State two reasons for which it is necessary for all sanitary fittings to be provided with individual traps.
(ii) Sketch a diagram that shows the position of a water seal in a water closet pan.
(c) List two properties of portable water.
Observation
Parts (a) and (b) posed some difficulty to the candidates. The required responses to these parts are given below.
5( a) Water hammer is a term used to describe a banging sound or noisy vibration which occurs when the flow of high pressure water is suddenly arrested in a water supply system.
(b) Reasons for providing all sanitary fittings with individual traps are:
- to prevent an appliance without a trap from releasing foul air into the building.
- to be as self-cleansing as possible.
- to prevent blockage.
- for ease of maintenance.
