Every organisation, however small, needs to know how long jobs take in order to carry out its business. The small retailer, the provider of a local service, the larger factory or farm, even public sector and other non profit making organisations cannot plan their work effectively without this information.
In a small or simple organisation, the data may not be collected in a formal manner, or even recorded at all, for the person who plans the work will probably just carry it out. But as firms grow larger or more complex it becomes desirable to make a specialist function of the setting of time standards, and the building up of data which can be used by people in the organisation who are responsible for planning, costing, scheduling and payments.
In the past, there is no doubt that Work Measurement, and especially its main technique, Time Study, gained a bad reputation due mainly to its misuse by certain firms and individuals. Specifically, this resulted from two main causes; firstly the confusing of Work Measurement with schemes, particularly 'Payment By Results Incentive Schemes', which use the data, and secondly the failure of management to realise that Work Measurement often highlights inefficiency in the organisation rather than that being attributed to the worker.
Work measurement consists of a series of techniques the purpose of which is to define tasks, measure them, and finally issue time standards to the people and departments who either use, or are affected by, the information.
The five main techniques used in measuring work are Time Study, Synthesis, Analytical Estimation, Pre-Determined Motion Time Systems and Activity Sampling.
Time study is a technique for recording the times and rates of working for the elements of a specified job, carried out under specified conditions; the data is analysed so as to obtain the time necessary to carry out the work at a defined level of performance (BS 31001).
Before commencing a Time Study it is necessary to break down the job into elements, an element being a distinctive part of the job, selected for the convenience of observation. The period from the beginning of the first element of the operation to the same point in a repetition of the operation is known as the Work Cycle. The instant at which one element in a work cycle ends and another begins is called the Break Point. It is necessary to break down work into elements for at least the following reassons:
- To ensure that effective time is separated from ineffective time.
- To permit the rate of performance to be assessed accurately.
- To enable the correct relaxation allowance to be given to each element.
- To enable time standards to be checked or modified in the light of future changes.
- To enable a Work Specification to be drawn up.
- To facilitate the compilation of Synthetic Times.
Historical ways at arriving at job times include reference to past records, timing a complete batch and estimation. These give accurate results and time study was developed in the interests both of accuracy and objectivity. Elements are usually timed witha stop-watch in three main ways; fly-back, cumulative and differential timing.
- Flyback Timing - uses a watch on which the hand, having recorded the length of an element, can be made to return to zero and immediately begin timing the next element.
- Cumulative Timing - here the hand of the watch moves continuously throughout the study. Reading of element times are taken as they occur, the time for each element being subsequently obtained by subtraction - some Trade Union Agreements were drawn up in the 1960's specifying only the use of continuous timing, since a view was held that time was lost to the operator in the flyback technique.
- Differential Timing - this is a method of obtaining the time for a very small element. Elements are timed in groups first including and then excluding the small element, the time for which is sbsequently obtained by subtraction.
Advantages and Disadvantages
- With the flyback method, no further calculations are needed to obtain elemental times. The subtraction needed with the continuous method can be a time consuming task on a long activity.
- The continuous method gives a total time for the study, but with the flyback method an independent check is needed.
- With the flyback method, a slight loss of time is experienced over a long study, but this should be negligible in the case of a trained and experienced Time Study Practitioner.
The British Standards Institute (BSI) suggested Rating Scale is that on which standard performance is designated by the figure '100'. On other rating scales, the standard performance figure is either '80' or '133', the scales being linear in all cases. BSI further suggests that times should be issued at standard or 100 performance. This departs from the practice of many firms whose times are issued at a lower definition point, namely 60 on the scale where 80 is standard performance. This somewhat artificial point was supposed by practitioners to denote the performance of a 'dayworker', or someone not incentivesed (motivated to achieve no more than the hourly rate) at work. Work Measurement is widely used for purposes other than the basis of incentive schemes and indeed in places where such schemes may never be applied. It is therefore considered that there is now no need for a lower point on the rating scale, and that standard performance only should be quoted, being equivalent to expected performance whether or not an operative is on any form of incentive.
Rating is the mental process by which a trained Time Study Practitioner compares the observed performance of each element with his own concept of standard performance. This is done as the study proceeds and a numerical value is given to the rating of each element. Most practitioners rate in multiples of five and all rate every element and not merely every cycle or the overall job. Opinions differ as to exactly what is rated, but it is generally accepted that speed and application are the two factors. It is also accepted that skill cannot be rated and that unless the person performing the task has sufficient skill to carry it out, the study should not be undertaken.
Calculations of Standard Times
Basic times are obtained by extending each observed time, that is by multiplying the observed time by the observed rating and dividing by standard rating. Each element of the job is timed not once, but many times, to give a reasonable average. We now have an average basic time for each element of the job. Before these can be added up to give us a standard time for the whole job, any additional allowances have to be considered. The most important of these is the Relaxation Allowance. The purpose of this is to provide the worker with the opportunity to recover from the physical and mental effects of the job and for any personal needs to be apportioned. This will vary from job to job and most organisations use a scale drawn up from their type of work having regard to various factors such as strenuousness, posture, eye strain, noise, heat, etc..
Another allowance which may occasionally be necessary is called the Contingency Allowance. This is to cover expected items of work or delay which are so small that to measure them would be impractical or uneconomical. It is suggested however, that this form of allowance should be avoided, if at all possible, and the item assessed as an element.
Any other allowance such as a policy allowance or modifications to standard times are outside the field of Work Study. Work Measurement, which is objective and free from any modifying factors, ends with the setting of a standard time and a clear distinction should be drawn between the setting of standard times and the administration of schemes which use those times.
The Work Specification
This is the form by which standard times are issued. It is a document setting out details of an operation, job or task, how it is performed, the layout of the workplace, particulars of any machines, tools or appliances used and the responsibilities of the operative. The standard time for the job is, of course, included.
This is the technique which builds up a time for a job by totalling element times, previously obtained from time studies on other jobs, containing the elements concerned.
Advantages of Synthetic Times
- They are based on data derived from a large number of studies and are therefore more accurate than times derived from a single study.
- They reduce the need for long individual studies.
- They add value to the field of estimating.
- They are useful during the planning stage of a job.
Great care is needed when compiling synthetic data to ensure that conditions are identical before accepting times from previous studies. The use of formulae and other calculations also needs careful checking. For these reasons, only fully trained and experienced Work Study Practitioners should attempt the building of a synthetic database.
This is a technique developed from estimating, where the time required to carry out elements of the job is estimated from knowledge and practical experience of the work concerned. It is mainly used on non-repetetive work where great accuracy is not required, for example, in planning maintenance schedules. It can never be as accurate as time study and should not be used for schemes where accurate data is essential. Analytical Estimation closely follows Time Study procedure as far as elemental breakdown, rating and allowances are concerned, although the actual times generated are estimated and not observed.
Pre-Determined Motion Time Systems
These are systems in which standard times are built up from data establishing times for basic human motions;
- The METHODS TIME MEASUREMENT (MTM) system has seven basic motions; reach, move, turn, grasp, position, disengage and release, each of which are sub-divided into types. Measurement is in Time Measurement (TM) Units, one of which is equivalent to one ten thousandth of an hour.
- The WORK FACTOR system is similar but it has eight basic motions; move, grasp, pick-up, pre-position, visually inspect, place aside, walk and turn.
An advantage claimed for these systems is that they focus attention on methods. A disadvantage lies in the difficulty of specifying conditions for, as in synthetics build up and use, identical conditions must be assured before time values can be used.
This is a technique used both in Method Study and Work Measurement. A large number of instantaneous random observations are made over a period of time. Each observation records what is happening at that instant and the percentage of observations recorded for a particular activity is a measure of the percentage of time during which the activity occurs. Advantanges of this technique are:
- A relatively unskilled person can be used for making the observations although the analysis of the data should be undertaken by a qualified practitioner.
- Several people or machines can be studied at once and many activities included.
- The person carrying out the study can attend to other duties in between making observations.
There are two pre-requisites to this technique. Firstly the study must cover a representative period, in other words, all periods must be covered, slack as well as busy. Secondly, observations must be made at random times and there must be a sufficient number of these. Fortunately, there are formulae and tables available to ensure that this is achievable.
The Use of Work Measurement Data
The main uses of Work Measurement Data are in the field of costing, planning and payment. It is perhaps worth noting here, that many organisations used to use Work Measurement purely as a basis for incentive schemes and were unaware of the useful data being lost to the process, once a particular batch of work had been completed and payment made. The full use of Work Measurement Data covers a significant arena. For the Planning Function, it can be used to plan orders, load the shop floor, predict delivery dates and progress the work. It can also form the basis of both cost estimation and the calculation of standard and actual costs. There are numerous types of incentive schemes, varying both as to the proportion of the basic wage on which bonus is paid, the performance at which payment starts and the rate of increase in reward as performance rises. Whatever type of scheme is deployed, desired or negotiated, Work Measurement Data is an integral part of the basis such schemes.
These subjects are outside the field of Work Measurement and should be dealt with as separate disciplines.
Human Problems and Work Measurement
Although the type of resistance to incorrectly applied Work Measurement, most common through the 1930's to the 1960's, is not prevalent today, human problems and concerns still exist. Furthermore, they are not confined to friction between Management Services Practitioners and operatives since Work Measurement also affects Managers, Planners, Cost Accountants and Wages personnel.
The secret of success in avoiding friction is twofold. - It is firstly to divorce Work Measurement from Incentive Scheme application, and secondly to keep operatives informed about the standard time data which will affect them. The way to achieve this is respectively, to retain Management Services Practitioners as the time standard setters and to administer the incentive schemes from the wages office. Furthermore copies of the Work Specifications should be available to appropriate departments with copies to the interested Trade Union parties, if applicable. Confidence will be gained if it is known that these specifications are actual copies of those issued to the wages, cost and planning departments.
When considering relations between management services practitioners and their 'customers', namely planners, cost clerks and wages clerks two things are essential - one is for the Management Services personnel to always be ready to help other departments in the use of the data, ensuring that it is issued in a form which is user friendly and easily understood. The second essential is that management services staff must never take over, even temporarily, the functions of other departments or indeed of management. Management Services must always be an advisory and not a controlling function.
Finally, an appeal must be made to management not to expect too much from Work Measurement. As has been stated, Work Measurement ends with the issuing of standard time data. Before any benefits can accrue, management and other specialists must learn how to use it. Many managers fail to realise this, assuming that merely establishing Work Measurement will generate ready-made schemes and guarantee savings. It should be emphasised that both Method Study and Work Measurement provide information which management has to evaluate and use before any benefits can be established.