Advantages of Time Study

Advantages of Time Study:

The advantages of time study are the applications to which time standards are put. Generally they are required (a) to plan future production and (b) to evaluate performance of workers or of the production system as a whole.

(a) To plan future production they are required for:

(1) Estimation of equipment or machinery requirements.

(2) Estimation of production cost per unit in order to determine/fix selling price.

(3) Estimating manpower requirements.

(4) Taking makes or buys decisions.

(5) Balancing the work of operators constituting a group.

(6) Estimating delivery dates.

(7) Estimating times required for a specified inventory level generation.

 

(8) Estimation of labour costs.

(9) Making alternative investment decision in purchasing machines/equipment.

(10) Developing efficient plant layout and material handling arrangement.

(b) Time standards help in evaluation of performance as in following cases:

(1) The evaluation of productivity of various workstations.

(2) The development of individual or group incentive schemes for above average performance.

Limitations of Time Study:

The followings are the limitations of time study as a technique of setting production standards:

(1) Standards cannot be established by this technique on jobs which are not well defined.

(2) In situations where it is difficult to define quality precisely standards and production incentives may cause deterioration in quality levels.

(3) It is not possible to maintain standards where piece rate system of wage payment exists.

(4) Labour unions may oppose the application of time study where they are strong.

(5) Time study is applicable only where the work is visible. So it can be applied only in manual job and not for thinking portions of the job.

(6) Only specific type of jobs which have identifiable starting and ending points can be timed accurately.

Length of Time Study:

The length of time study will affect the accuracy where bias may result if the period of study is too short to include all the significant variables. Traditional time study practice usually limits the study to observing net cycle time over a relatively short time period to include essential between-cycle variations.

Consideration is usually given to between-hour and between day variations by taking the observations during, say, the middle of the morning work period and during the second or third day of the work week, when it is assumed that the production rate is average as far as these sources of variation are concerned.

Number of Cycles to be Timed:

Time required to perform an element of an operation varies slightly from cycle to cycle. However, this variation can be reduced to some extent by using highly standardized raw materials, good tools and equipment’s, good working conditions and a qualified and well trained operator, but the variation cannot be avoided completely.

Time study is a sampling process, therefore, large number of readings should be taken so that the results will be representative of the activity being measured and the desired accuracy may be obtained.

Experience has shown that 95% confidence level and ± 5% accuracy is sufficient for time study. From statistics, for this condition, number of cycles to be timed can be found by the following relation.

where N = Required number of observations to predict the little time with in ±5% accuracy and 95% confidence level.

X = Each stop watch reading.

M = No. of stop watch readings.