Work Measurement Techniques
Image depicts different work measurement techniques, methods or types.
Work measurement techniques are listed below:
- Historical data method - It uses the past performance data to set performance standards.
- Time study - It uses stop watch and is best suited for short-cycle repetitive jobs.
- Work sampling - Here, workers are observed many times at random.
- Synthesis method - Here, the full job is divided into element or parts.
- Predetermined motion time system (PMTS) - Here, normally, three times are fixed for one job namely; normal, fast, and very-fast.
- Analytical estimating - It is used for fixing the standard time for jobs, which are very long and repetitive.
Now lets discuss more above techniques of work measurement.
1. Historical data method
Historical data method uses the past-performance data. Here, past performance is used as a guideline for setting work performance standards. The main advantage of this technique is that it is simple to understand, quicker to estimate and easier to implement. However, past performance is not the best basis for fixing performance standards. This is because there may be many changes in technology, employees behavior, abilities, etc.
2. Time study
Time study with the help of a stop watch is the most commonly used work measurement method. This technique was developed by Frederick Winslow Taylor (1856-1915).
Time study is best suited for short-cycle repetitive jobs. Most of the production jobs can be easily timed by a time-study.
Time study procedure consists of the following steps:
- Select the job to be timed.
- Standardize the method of doing the job.
- Select the worker to be studied.
- Record the necessary details of the job and conditions of work.
- Divide the job into elements. Here, element is a part of the job.
- Find out the time taken to do every single element.
- Keep provisions for relaxation, etc.
- Fix the standard time for doing the job.
3. Work sampling
Work sampling method was original developed by Leonard Henry Caleb Tippett (1902-1985) in Britain in 1934. In this technique, the workers are observed many times at random. It is done to find out for how much time the worker is actually on the job. It checks how long he is working and how much time he is not working (idle time).
Work sampling method does not involve stop watch measurement. The purpose of work sampling technique is to estimate what proportion of a workers time is devoted to work-related activities.
Work sampling method involves following three main steps:
- Deciding what activities are defined as working. Non-working are those activities which are not defined as working.
- Observe the worker at selected intervals and record (write down) whether he is working or not.
- Calculate the portion of time (P), a worker is working.
A portion of time (P) a worker is working equals to Number of observations during which working occurred divided by Total Number of observations.
The above calculation is used as a performance standard.
To know more, read advantages and disadvantages of work sampling.
4. Synthesis method
In synthesis method, the full job is first divided into elements (parts). Then the time taken to do each element of the job is found out and synthesized (totaled). This gives the total time taken for doing the full job. In this technique, the time taken to do each element of the job is found out from previous time studies. So, this technique gives importance to past-time studies of similar jobs. It also uses standard data.
Standard-data is the normal time taken for doing routine jobs. Standard data is easily available for routine-jobs like fitting screws, drilling holes, etc. So there is no need of calculating these times repeatedly. Most companies use Standard-data. They do not waste time doing studies for all elements of the job. This is because standard time is already available for most elements of a job.
For example, a job of publishing a book contains four elements viz; typing, editing, printing and binding. The time taken for doing each element is first found out. Suppose, typing takes 40 days, editing takes 30 days; printing takes 20 days and binding takes 10 days. Then the time taken to do all the elements are totaled. That is, it takes 40 + 30 + 20 + 10 = 100 days to publish a book. This information is taken from previous time studies of other printing jobs or from the standard data.
Synthesis technique also considers the level of performance. Level of performance refers to the speed of performance, which is either, normal, fast, or very-fast.
The benefits or advantages of synthesis method:
- It provides reliable information about standard time for doing different jobs. This is because it is based on many past time studies.
- It is economical because there is no need to conduct new time studies.
5. Predetermined motion time system
In Predetermined Motion Time System method or simply PMTS technique, the normal times are fixed for basic human motions. These time values are used to fix the time required for doing a job. Normally, three times are fixed for one job. That is, one time is fixed for each level of performance. The level of performance may be normal, fast and very-fast.
PTMS is better than motion studies because it gives the detailed analysis of the motion, and it fixes the standard time for doing that motion.
PTMS technique is used mostly for jobs, which are planned for future. However, it can also be used for current jobs as an alternative to time study.
The benefits or advantages of PMTS method:
- It is a very accurate method. It avoids subjective judgement or bias of rater.
- It is an effective and economical method for repetitive jobs of short duration.
- There is no interference in the normal work routine, and so it does not face any resistance from the employees.
- It helps to improve the work methods because it gives a detailed analysis of the motions.
- It is more economical and fast compared to normal time studies.
6. Analytical estimating
Analytical estimating method or technique is used for fixing the standard time for jobs, which are very long and repetitive. The standard-time is fixed by using standard-data. However, if standard data is not available, then the standard time is fixed based on the experience of the work-study engineer.
The benefits or advantages of analytical estimating technique:
- It helps in planning and scheduling the production activities.
- It provides a basis for fixing labor rate for non-repetitive jobs.
- It is economical because it uses standard data for fixing the standard time of each job.
One disadvantage or limitation of analytical estimating method:
- When standard-data is not available for a job, then the standard time is fixed by the work-study engineer. He uses his experience and judgement for estimating the standard-time. This is not accurate compared to a scientific time study.
So, these are different techniques of work measurement.