PRINCIPLES AND TECHNIQUES:WORK MEASUREMENT AND AN OVERVIEW

1. WORK MEASUREMENT: AN OVERVIEW

Work measurement, as the name suggests, provides management with a means of measuring the time taken in the performance of an operation or series of operations. Work measurement is the application of techniques designed to establish standard times for a qualified worker to carry out a specified job at a defined level of performance. With today’s increasing global competition among producers of products or providers of service, there has been an increasing effort to establish standards based on facts and scientific methods rather than the use of estimates based on judgment or experience (Niebel and Freivalds 1999). Sound standards have many applications that can mean the difference between the success or failure of a business. Accurately established time standards make it possible to produce more within a given plant, thus increasing the efficiency of the equipment and the optimal utilization of personnel. Poorly established standards, although better than no standards at all, lead to high costs, low productivity, and labor unrest.

Common uses of work measurement include the following:

• To compare the efficiency of alternative methods. Other conditions being equal, the method that takes the least time will be the best method.

• To balance the work of members of teams, in association with multiple activity charts, so that, as nearly as possible, each member has tasks taking an equal time to perform.

• To determine, in association with man and machine multiple activity charts, the number of machines an operator can run.

• To provide information on which the planning and scheduling of production can be based, including plant and labor requirements for carrying out the program of work, the utilization of available machine and labor capacity, and delivery promises.

• To provide information for labor cost control and to enable standard costs to be fixed and maintained.

• To provide information on which incentive plans can be based.

Time standards are always based on a specific method and working conditions. As time passes, improvements may be introduced, whether by the supervisor, the methods engineer, management, or the operator. Regardless of who introduced the method changes, they will directly affect the time standard being applied. This should signal the need for the method to be restudied and reevaluated. The time study analyst should be advised of such changes so that the portion of the operation that is affected by the change can be reviewed and the time standard recalculated.

To ensure that the methods applied when the time study was conducted are still being employed, regular audits should be scheduled by the time study analysts. The more frequently a standard is applied, the more frequent the audits should be. Time study audits do not necessarily lead to con- ducting a time study of the entire method. If, however, a major modification in the method is observed (e.g., change in tools used, different sequence in operations, change in materials processed, change in process or approach), then a new detailed study must be performed.

1.1. Basic Procedure of Work Measurement

In general, the basic procedure of work measurement uses the following steps:

1. Select the work to be studied.

2. Record all the relevant data relating to the circumstances in which the work is being done, the methods, and the elements of activity in them.

3. Examine the recorded data and the detailed breakdown critically to ensure that the most ef- fective method and motions are being used and that unproductive and foreign elements are separated from productive elements.

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4. Measure the quantity of work involved in each element in terms of time using the appropriate work-measurement technique.

5. Calculate the standard time for the operation, which in the case of stopwatch time study will include time allowances to cover relaxation, personal needs, etc.

6. Define precisely the series of activities and method of operation for which the time has been compiled and issue the time as standard for the activities and methods specified.

1.2. Work Measurement Techniques

Operations managers and engineering staff need to be aware of the many different work measurement techniques that are available so that they can make appropriate choices as operating conditions change. Successful installation of any of the work-measurement techniques needs the full support of management to commit the time and financial resources necessary on a continuing basis. The objec- tive of this chapter is to discuss these different alternatives, compare their advantages and disadvan- tages, and offer some guidelines for proper selection and application.

There are four types of work measurement techniques: time study, predetermined time standards (PTS), standard data, and work sampling. All of these techniques are based on facts and consider each detail of work. The first three techniques measure the normal time required to perform the entire work cycle. Work sampling measures the proportion of time of various work activities that constitute a job. Table 1 describes these techniques and where each is appropriately used. Table 2 provides a further comparison among work measurement techniques in terms of their advantages and disadvan- tages.