Most candidates were able to:
- sketch the conventional symbol for the given electrical installation
fittings;
- state the functional requirements of a drainage scheme.
However, few candidates were unable to
- explain the causes of accident during roof construction;
- state the precautionary measures to be observed when operating a
concrete mixer.
The expected response to question 5 is as given below:
(a)
(b) Functional requirements of a drainage scheme are:
- Must be constructed of sound materials.
- Must have adequate gradient.
- Must be self-cleansing.
- Must have means of access for inspection and maintenance.
- Must have airtight/water tight joint.
- Must have unobstructed bore.
- Must be well ventilated.
- Should prevent back siphonage and built up of explosive gas.
(c) Causes of accident during roof construction are:
- Use of inferior materials for its construction.
- Improper erection of scaffolding.
- Roof pitch being too steep.
- Unstable scaffold.
(d) Precautionary measures to be observed
- ensure the protective guard of the mixer is in place
- operator must wear nose mask, hard boots, helmet and overall
- machine must be in good working condition
- machine must be operated by competent person
- capacity of mixer must not be exceeded
- to be cleaned and oiled after use.
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