WORK MEASUREMENT

CONTENTS Introduction Characteristics Objectives Procedure Importance Techniques Work measurement techniques chart Ergonomics Work standards and standardization Work simplification

Work Measurement Work measurement is the application of techniques designed to establish the time for an average worker to carry out a specified manufacturing task at a defined level of performance. It is concerned with the length of time it takes to complete a work task assigned to a specific job. It is concerned with evaluation of output with references to a standard.

CHARACTERISTICS Standardised Comparable Exact not Vague Understandable

Objectives Establishing standard times for completion of specific tasks Checking performance with standards Measuring machine output Facilitating the introduction and effective use of costing Providing fair basis for incentive schemes

Procedure Identify and select all those activities that are to be timed. Care has to be taken while choosing an operator of average ability. Clear cut definitions of the methods in use are to be made so that no confusion arise. In order to measure the work, the unit should generally be timed. We should calculate a basic time for each work unit that is measured, by making use of stop watch. Necessary relaxation allowances should be made for fatigue, rest, variations between operations and so on. Finally, we should base the standard time on delay long average time by calculating it on the basis of time taken to complete a task by a competent operative, maintaining a set standard of quality performance.

Importance Helps in reduction of ineffective time It suggests rest intervals to the operators so as to enhance their efficiency Helps in production planning and control Helps in estimation of manpower requirements and their proper utilization Provides basis for wages and salary administration

Analytical Estimating Techniques Direct Method Indirect Method Time Study Synthetic Timings PMTS Activity Sampling Analytical Estimating

1. Time Study Time study involves fixing the standard time for doing a job under given conditions. It involves a careful analysis and observation of the time required to do a given job.

Objectives of Time Study To fix standard time required for an operation under normal circumstances To use standard time data so as to fix a fair incentive wage plan To avoid abnormal idle time and delay in the execution of job To create time consciousness in the workers To control and reduce costs To set a fair hourly output standard for worker To improve working conditions

(i.) Stop watch time – it is used for setting standards. Selection and description of the exact repetitive type operations to be studied on the basis of the assumptions of a standard method. Collecting the necessary items to be made use of, including a stop watch, a clip board and observation sheets. Selection of the operator who is to be observed and obtaining the co-operation of the concerned line supervisor. Identifying precisely the timing points and elements of the operation. Determining the no. of cycles that are to be timed.

Making the actual observations ad recording them on the observation sheet, coupled with a simultaneous rating of the performance of the particular worker. Computing the measure of central tendency that represents the detailed time values in order to arrive at the ‘base time’. Calculating the normal time with the help of performance rating of the worker observed. Calculating the standard time by providing for the necessary allowances (like relaxation allowance for the possible fatigue, rest, operational variations, unavoidable delays etc.).

(ii.) Performance Rating Performance rating is determining the relative speed at which the workers work. Rating the speed of the worker is based on the judgement of the time study analyst. Two methods of rating are : (i.)Westinghouse Rating : it considers 4 factors i.e., namely skill, effort, working condition and consistency. (ii.) 100% Rating System : the operator is said to be working at 100% pace if he is working at an average pace.

(iii.) Allowances – workers are not machines and cannot be expected to work continuously through out the day without relaxation. Process Allowance Relaxation Allowance Contingency Allowance

Benefits of Time Study Helps in setting of production schedules for use in production planning and control Helps to measure the efficiency of each worker by laying down standards It aids management to formulate a sound wage policy and incentive schemes It creates time consciousness in workers Helps in reduction of costs It enables computation of standard costs

It helps in improving the working conditions It enables management to evaluate alternative methods of work by time comparisons and thus to find out ‘the one best way’ of doing a job

Limitations of Time Study It cannot be undertaken until product, equipment, working conditions and working method are all standardised. Not of much use for jobs repetitve in nature. Standards based upon time study affect adversely the quality of the product. Standards are difficult to set on indirect labour jobs such as clerical and supervisory staff. Incorrect standards may be fixed.

Activity Sampling Activity sampling also called work sampling represents another technique of work measurement that has gained increased attention these days. As the name suggests activity sampling involves the application of statistical sampling to jobs or activities. N= pqz²/a² N = no. of observations p = percentage of item/persons possessing a particular characteristic in the sample drawn q = percentage of items/persons not possessing the particular characteristic in the sample drawn (1-p) a = desired accuracy z = desired confidence level

Procedure: The total working time of all workers who perform the operations is broken down into instants of time that are used as the basic unit of sampling. The exact instants of time for actual observations are determined by some random method. The observer tallies the action occuring at a large number of different instants of time. Afterwards, the total number of instants at which each type of activity has been observed is divided by the total number of observations.

The results he gets represent the percentages of instants at which each type of activity was observed. These percentages serve as the basic data provided by work sampling. They are very useful because they yield directly whatever information that is considered necessary for determining allowances.

Merits of work sampling Suitable for jobs with long cycle time. Activities which are costly to measure by time study can be measured by work sampling. It requires less man hours to conduct a work sampling study as compared to time study. Single observer can conduct several work sampling studies simultaneously. No timing device is required. Observer need not be a trained analyst. It is less tedious and less fatiguing.

Demerits Insufficient observations may produce inaccurate results. The technique is uneconomical for short cycle jobs. The work sampling technique is a statistical technique which may not be easily understandable to the management and workers. The technique does not normally account for the speed of the operator.

Indirect method Predetermined motion time system (P.M.T.S) PMTS is based on the analysis of work into basic human movements, classified according to the nature of each movement and conditions under which it is made. In this individual movements are analyzed and then the time required for these motions is determined. Popular systems like M.T.M. is installed now a days. Both motion and time study are complementary to each other. Time study is necessary to measure the economies of motion study so as to find ‘the one best way’ of doing a job.

Tools of motion study Process charts Applications of Laws of Motion economy Preparation of questionnaires Therbligs Micro-motion study

Process charts A chart may be a diagram, a picture or a graph which gives an overall view of a situation, say a process. All the details about an existing methods/ process are recorded and represent in chart.

b)Laws of motion economy This principle form a set of rules: Both hands should work and rest at the same time Motions of arm should be made in opposite and symmetrical direction. Work should be arranged to permit an easy and natural rhythm where ever is possible.

c)Preparation of questionnaire Questionnaire means a set of printed or written questions with the choice of answers devised for the purpose of a survey. Some questions can be asked like: How , when, where and why job is to be done? Can some operations be done by machines? Can we combine operations?

d)Therbligs The word therblig was the creation the Frank B Gilbreth and Lillian Moller Gilbreth. It is the reversal of the name Gilbreth. Therbligs are 18 kinds of elemental motions used in the study of motion economy in the workplace.

e)Micro motion study Micro motion study technique is best suited for those operations or activities which are of short duration and which are repeated hundred of times. This study can be done with the help of high speed films. Thus micro motion study is the technique of recording and analyzing the timing of basic elements of an operation with the objective of achieving the best method of performing the operation.

The results obtained are consistent Advantages of PMTS An estimate of work content can be obtained even before the task is actually carried out The results obtained are consistent The system helps in setting targets Disadvantages It lays down certain pattern of motions, which if employed, becomes monotonous. It fixes standards which may not be achievable and hence disliked by workers It affects initiative and creativeness of workers.

synthetic Time Standards/synthesis Synthesis is another technique which builds up standard times using data obtained from previous Time studies. Although the setting of times by synthesis is similar to PMTS, but the distinguishing point in the case of times set by synthesis is that these times are not set on elements as basic as those detailed under PMTS (therbligs).

Advantages Helps in reduction of unnecessary time studies of work similar in nature. Reduction in cost Reduction in delays for setting time standards for a job Consistency in time standards

Analytical estimating In this technique, the estimating is done by a skilled and experienced worker who has had training in the process of estimating and who simply estimates the time that would be required by a fully competent and experienced worker, working at a defined level of performance. This is done when the operations are of non repetitive in nature, of short duration and also not studied previously. this technique is applied in repair and maintenance work, tool rooms, office routine jobs etc.

Ergonomics Ergonomics has been defined as ‘fitting the job to the workers’. it is concerned with the study of man in relation to his working environment with special reference to physical posture. It aims at reducing fatigue and increasing the efficiency by a scientific design of setting based on knowledge.

Ergonomics is a superior management technique compared to work measurement.

To achieve the best practice design, Ergonomists use the data and techniques of several disciplines: Anthropometry: body size, shapes, Biomechanics: muscles forces, strength Environmental physics: noise, light, heat, cold, radiation. Applied psychology: skill, learning Social psychology: groups, communication, behaviors.

Areas covered by ergonomics The work place - it includes the layout of equipment General environment – it includes the effect of heat, lighting, noise, vibration affecting the health of an individual. Other related factors – which includes fatigue, vigilance and inspection

Work standards and standardization Standardization is defined as a process of determining uniform methods for performance of each activity and is concerned with bringing uniformity in work conditions, equipments routines or procedure. It is precondition for fixation of standards. Standards may be determined in quantify, quality, cost, time etc.

Process of Standardization Determine the needs and objects Determine the area of Standardization Study & analysis of existing method of work Determine various alternatives methods Selection and installation of new method

Work simplification Work simplification means an organized application of commonsense by everyone to eliminate waste of any kind – time, energy, space, men, money, material. The main objective of work simplification is to increase efficiency, bring economy and effectiveness through elimination, mechanisation, combination, and simplification.

Steps Select work to be simplified Record all facts about the work Develop most practical, economical and effective method of doing work with reference to the work situation. Maintain the method by regular checks.