Levelling is a Work Measurement technique used to 'rate' utilising a 'levelling factor' determined by reference to a table of point values for various grades of skill and effort (and sometimes also conditions and consistency). The algebraic sum of the point values assigned to each factor is used in adjusting the observed time to give an allowed time required at a stated performance level.
The student in researching this technique should familiarise him/herself with the terms 'rate', 'skill', 'effort' and 'consistency' in determining the value of this technique;
In this system the Time Study Engineer - the only person qualified to undertake this specialised technique - judges the performance rating for the basic time of each operation element using a table of factors. In the case of the Westinghouse Electric & Manufacturing Corporation (USA), the operator is rated on 4 (four) factors namely skill, effort, conditions and consistency.
For example, see the table below, if the operator is rated B1 for skill, B1 for effort, D for conditions and A for consistency for the complete study then the levelling factor is equal to 1 plus 0.11 + 0.10 + 0.00 + 0.04 equating to 1.25 (levelling factor - i.e. 125% performance.
Therefore if an observed actual time was 0.50 min and the applied levelling factor 1.25, then the 'allowed time' is 0.50 @ 1.25 = 0.625 min.
The table below sets out a typical levelling factor chart as applied throughout industry in the 1960's. The factors considered when undertaking Time Study (viz. skill, effort, conditions & consistency) would be comparable to the use of the the Levelling technique and it is considered advisable to periodically check consistency of approach and results achieved with formal time studies.
|SKILL||% CHANGE||RANGE||EFFORT||% CHANGE||RANGE|