There is no single or exact method to determine
production efficiency factor as there are too many factors involved, and it is
neither feasible nor desirable to evaluate the effect of all such factors
affecting production efficiency. At the planning stage, a project planner or
estimator cannot take care all the controllable and enforceable factors. It is
possible that some of these may have been considered while establishing the
basic productivity norms.
Further, it is not necessary to consider the effect of
all the factors while modifying basic norms as some of these may overlap, while
a few may have only a marginal effect on overall productivity. It is better to
limit the computation of adjustment in productivity to four to six prominent
factors which contribute significantly to overall productivity, and omit other
factors. By using his experience and skill, the planner identifies the
main factors that affect productivity, evaluates their implications, and
finally transforms the basic productivity norms into workers productivity
standards conforming in the characteristics of the project under consideration.
Another approach to evaluate the main factors that
influence workers production efficiency is to divide the production efficiency
range into three basic ranges corresponding to ‘low’, ‘average’, and ‘high’
productivity conditions. The low condition ranges from 40-60% efficiency,
average from 60-80% and high from 80-100%.
Each major factor affecting efficiency is the
evaluated considering the site conditions. This evaluation, for a typical
project, is given below:
Production
Elements
|
Efficiency
(in
%)
|
Nature of
work
|
75
|
Supervision
|
90
|
Labour
Market
|
80
|
Climate
and working conditions
|
60
|
Equipment
orientation
|
50
|
Total
|
355
|
The average production efficiency (355/5) is 71.0% of
the basic productivity norms. The standard productivity for each item of work
is then obtained by multiplying the basic norms with the evaluated average
production efficiency factor of the work process. However, this structured
approach only provides guideline and its outcome can best be taken as an
approximate to be further scrutinized by the planner and construction engineers.
The worker’s productivity
data used in the initial stages of the planning process may not necessarily be
the worker’s productivity standards used for controlling worker’s performance.
During the execution stage, the initially assessed productivity is subjected to
further reviews, if necessary.
