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Part Two
Design
Qualified worker
Defined level of
performance
Specified job
Standard performance
Synthesis from elemental
data
Predetermined motiontime
systems
Analytical estimating
Activity sampling
‘measurement’ could be regarded as indicating a somewhat spurious degree of accuracy.
Formally, work measurement is defined as ‘the process of establishing the time for a qualified
worker, at a defined level of performance, to carry out a specified job’. Although not a precise
definition, generally it is agreed that a specified job is one for which specifications have been
established to define most aspects of the job. A qualified worker is ‘one who is accepted as
having the necessary physical attributes, intelligence, skill, education and knowledge to perform
the task to satisfactory standards of safety, quality and quantity’. Standard performance
is ‘the rate of output which qualified workers will achieve without over-exertion as an average
over the working day provided they are motivated to apply themselves to their work’.
The techniques of work measurement
At one time, work measurement was firmly associated with an image of the ‘efficiency expert’,
‘time and motion’ man or ‘rate fixer’, who wandered around factories with a stopwatch, looking
to save a few cents or pennies. And although that idea of work measurement has (almost)
died out, the use of a stopwatch to establish a basic time for a job is still relevant, and used in
a technique called ‘time study’. Time study and the general topic of work measurement are
treated in the supplement to this chapter – work study.
As well as time study, there are other work measurement techniques in use. They include
the following.
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Synthesis from elemental data is a work measurement technique for building up the time
for a job at a defined level of performance by totalling element times obtained previously
from the studies in other jobs containing the elements concerned or from synthetic data.
Predetermined motion-time systems (PMTS) is a work measurement technique whereby
times established for basic human motions (classified according to the nature of the
motion and the conditions under which it is made) are used to build up the time for a job
at a defined level of performance.
Analytical estimating is a work measurement technique which is a development of
estimating whereby the time required to carry out the elements of a job at a defined level
of performance is estimated from knowledge and experience of the elements concerned.
Activity sampling is a technique in which a large number of instantaneous observations are
made over a period of time of a group of machines, processes or workers. Each observation
records what is happening at that instant and the percentage of observations recorded
for a particular activity or delay is a measure of the percentage of time during which that
activity or delay occurs.
Critical commentary
The criticisms aimed at work measurement are many and various. Amongst the most
common are the following:
● All the ideas on which the concept of a standard time is based are impossible to define
precisely. How can one possibly give clarity to the definition of qualified workers, or
specified jobs, or especially a defined level of performance?
● Even if one attempts to follow these definitions, all that results is an excessively rigid
job definition. Most modern jobs require some element of flexibility, which is difficult to
achieve alongside rigidly defined jobs.
● Using stopwatches to time human beings is both degrading and usually counterproductive.
At best it is intrusive, at worst it makes people into ‘objects for study’.
● The rating procedure implicit in time study is subjective and usually arbitrary. It has no
basis other than the opinion of the person carrying out the study.
● Time study, especially, is very easy to manipulate. It is possible for employers to ‘work
back’ from a time which is ‘required’ to achieve a particular cost. Also, experienced staff
can ‘put on an act’ to fool the person recording the times.