Work sampling is a work measurement technique that randomly samples the work of one or more employees at periodic intervals to determine the proportion of total operations that is accounted for in one particular activity.
These studies are frequently used to estimate the percentage of time spent by the employees in unavoidable delays(commonly called ratio-delay studies), repairing finished products from an operation and supplying material to an operations.
Uses of Work Sampling Technique
(i) To estimate the percentage of a protracted time period consumed by various activity states of a resources such as equipment, machines or operators.
(ii) To determine the allowances for inclusion in standard times.
(iii) To indicate the nature of the distribution of work activities within a gang operation.
(iv) To estimate the percentage of utilization of groups of similar machines or equipment.
(v) To indicate how material handling equipments are being used.
(vi) To provide a basis for indirect labor time standards.
(vii) To determine the productive and non-productive utilization of clerical operations.
(viii) To determine the standards time for a repetitive operation as an alternatives to the stop watch method.
Work Sampling Procedure
In work sampling study, the works study engineer takes a great number of observations of a worker or machine random times throughout the working shift or day. He records precisely what the worker or the machine is doing(i.e. working or idle) at the time of observation. No stop-watch is used. The objective is to find the frequency of occurrence of every work element.
The technique is based upon the laws of probability. It is based on the statistic
Premise that, the occurrences in an adequate random sample observations of a
activity will follow the same distribution pattern that might be found in a lengthy,
continuous study of the same activity
P= x / N = No of observations of the activity / Total No of observations