Work Systems Design

10.	Work Systems Design The following are examples of approaches to work systems design that have been used in an attempt to bring these desirable job characteristics to people’s work leading to an improved mental state and thus increased performance.
	10.1.	Job Enlargement This involves the horizontal integration of tasks to expand the range of tasks involved in a particular job. If successfully implemented this can increase task identity, task significance and skill variety through involving the worker in the whole work task either individually or within the context of a group. Job Rotation is a common form of job enlargement and involves a worker changing job roles with another worker on a periodic basis. If successfully implemented this can help increase task identity, skill variety and autonomy through involvement in a wider range of work task with discretion about when these mix of tasks can be undertaken. However this method does not actually improve the design of the jobs and it can mean that people gravitate to the jobs that suit them and are not interested in initiating rotation with colleagues. At worst it can mean rotation between a number of boring jobs with no acquisition of new skills.
	10.2.	Job Enrichment Job enrichment involves the vertical integration of tasks and the integration of responsibility and decision making. If successfully implemented this can increase all five of the desirable job characteristics by involving the worker in a wider range of tasks and providing responsibility for the successful execution of these tasks. This technique does require feedback to so that the success of the work can be judged. The managerial and staff responsibilities potentially given to an employee through enrichment can be seen as a form of empowerment. This should in turn lead to improved productivity and product quality
	10.3.	Implementation of Work Design Approaches There are a number of factors which account for the fact that job enlargement and job enrichment are not more widely implemented. Firstly the scope for using different forms of work organisation will be dependent to a large extent on the type of operation in which the work is organised. Job shop manufacturing will require skilled workers who will be involved in a variety of tasks and will have some discretion in how they undertake these tasks. Sales personnel may also have a high level of discretion in how they undertake their job duties also. The amount of variety in a batch manufacturing environment will to a large extent depend on the length of the production runs used. Firms producing large batches of a single item will obviously have less scope for job enrichment than firms producing in small batches on a make-to-order basis. One method for providing job enlargement is to use a cellular manufacturing system, which can permit a worker to undertake a range of tasks on a part. When combined with responsibility for cell performance this can lead to job enrichment. Jobs in mass production industries may be more difficult to enlarge. Car plants must work at a certain rate in order to meet production targets and on a moving line it is only viable for each worker to spend a few minutes on a task before the next worker on the line must take over. A way of overcoming this problem is to use teams. Here tasks are exchanged between team members and performance measurements are supplied for the team as a whole. This provides workers with greater variety and feedback, but also some autonomy and participation in the decisions of the team. Secondly financial factors may be a constraint on further use. These may include the performance of individuals who actually prefer simple jobs, higher wage rates paid for the higher skills of employees increasing average wage costs and the capital costs of introducing the approaches. The problem is that many of the benefits associated with the technique, such as an increase in creativity, may be difficult to measure financially. Finally the political aspects of job design changes have little effect on organisational structures and the role of management. Although job enrichment may affect supervisory levels of management, by replacement with a team leader for example, the power structures in which technology is used to justify decisions for personal objectives is intact
	10.4.	Methods Analysis Dividing and analysing a job is called method study. The approach takes a systematic approach to reducing waste, time and effort. The approach can be analysed in a six-step procedure :
		1.	Select Tasks most suitable will probably be repetitive, require extensive labour input and be critical to overall performance.
		2.	Record This involves observation and documentation of the correct method of performing the selected tasks. Flow process charts are often used to represent a sequence of events graphically. They are intended to highlight unnecessary material movements and unnecessary delay periods.
		3.	Examine This involves examination of the current method, looking for ways in which tasks can be eliminated, combined, rearranged and simplified. This can be achieved by looking at the flow process chart for example and re-designing the sequence of tasks necessary to perform the activity.
		4.	Develop Developing the best method and obtaining approval for this method. This means choosing the best alternative considered taking into account the constraints of the system such as the performance of the firm’s equipment. The new method will require adequate documentation in order that procedures can be followed. Specifications may include tooling, operator skill level and working conditions
		5.	Install Implement the new method. Changes such as installation of new equipment and operator training will need to be undertaken.
		6.	Maintain Routinely verify that the new method is being followed correctly New methods may not be followed due to inadequate training or support. On the other hand people may find ways to gradually improve the method over time. Learning curves can be used to analyse these effects.
	10.5	Motion Study Motion study is the study of the individual human motions that are used in a job task. The purpose of motion study is to try to ensure that the job does not include any unnecessary motion or movement by the worker and to select the sequence of motions that ensure that the job is being carried out in the most efficient manner possible. For even more detail videotapes can be used to study individual work motions in slow motion and analyse them to find improvement - a technique termed micromotion analysis. The principles are generally categorised according to the efficient use of the human body, efficient arrangement of the workplace and the efficient use of equipment and machinery. These principles can be summarised into general guidelines as follows :
		-	Efficient Use of the Human Body Work should be rhythmic, symmetrical and simplified. The full capabilities of the human body should be employed. Energy should be conserved by letting machines perform tasks when possible
		-	Efficient Arrangement of the Workplace Tools, materials and controls should have a defined place and be located to minimise the motions needed to get to them. The workplace should be comfortable and healthy.
		-	Efficient use of Equipment Equipment and mechanised tools enhance worker abilities. Controls and foot-operated devices that can relieve the hand/arms of work should be maximised. Equipment should be constructed and arranged to fit worker use.
		Motion study is seen as one of the fundamental aspects of scientific management and indeed it was effective in the design of repetitive, simplified jobs with the task specialisation which was a feature of the mass production system. The use of motion study as declined as there as been a movement towards greater job responsibility and a wider range of tasks within a job. However the technique is still a useful analysis tool and particularly in the service industries, can help improve process performance.
	10.6.	Work Measurement The second element of work-study is work measurement which determines the length of time it will take to undertake a particular task. This is important not only to determine pay rates but also to ensure that each stage in a production line system is of an equal duration (i.e. ‘balanced’) thus ensuring maximum output. Usually the method study and work measurement activities are undertaken together to develop time as well as method standards. Setting time standards in a structured manner permits the use of benchmarks against which to measure a range of variables such as cost of the product and share of work between team members. However the work measurement technique has been criticised for being misused by management in determining worker compensation. The time needed to perform each work element can be determined by the use of historical data, work sampling or most usually time study.
		10.6.1.	The purpose of Time Study is through the use of statistical techniques to arrive at a standard time for performing one cycle of a repetitive job. This is arrived at by observing a task a number of times. The standard time refers to the time allowed for the job under specific circumstances, taking into account allowances for rest and relaxation. The basic steps in a time study are indicated below :
			1.	Establish the standard job method It is essential that the best method of undertaking the job is determined using method study before a time study is undertaken. If a better method for the job is found then the time study analysis will need to be repeated
			2.	Break down the job into elements The job should be broken down into a number of easily measurable tasks. This will permit a more accurate calculation of standard time as varying proficiencies at different parts of the whole job can be taken into account.
			3.	Study the job This has traditionally been undertaken with a stopwatch, or electronic timer, by observation of the task. Each time element is recorded on an observation sheet. A Video camera can be used for observation, which permits study away from the workplace, and in slow motion which permits a higher degree of accuracy of measurement.
			4.	Rate the worker’s performance As the time study is being conducted a rating of the worker’s performance is also taken in order to achieve a true time rating for the task. Rating factors are usually between 80% and 120% of normal. This is an important but subjective element in the procedure and is best done if the observer is familiar with the job itself.
			5.	Compute the average time Once a sufficient sample of job cycles have been undertaken an average is taken of the observed times called the cycle time. The sample size can be determined statistically, but is often around five to fifteen due to cost restrictions.’
			6.	Compute the normal time Adjust the cycle time for the efficiency and speed of the worker who was observed. The normal time is calculated by multiplying the cycle time by the performance rating factors. Normal Time (NT) = cycle time (CT) x rating factor (RF)
			7.	Compute the standard time The standard time is computed by adjusting the normal time by an allowance factor to take account of unavoidable delays such as machine breakdown and rest periods. The standard time is calculated as Standard Time (ST) = Normal Time (NT) x allowance
		10.6.2.	Predetermined Motion Times One problem with time studies is that workers will not always co-operate with their use, especially if they know the results will be used to set wage rates. Combined with the costs of undertaking a time study, a company may use historical data inthe form of time files to construct a new standard job time from previous job element. This has the disadvantage however of the reliability and applicability of old data. Another method for calculating standard times without a time study is to use predetermined motion time system (PMTS) which provides generic times for standard micromotions such as reach, move and release which are common to many jobs. The standard item for the job is then constructed by breaking down the job into micromotions that can then be assigned a time from the motion time database. The standard time for the job is the sum of these micromotion times. Factors such as load weight for move operations are included in the time motion database. The advantages of this approach are that standard times can be developed for jobs before they are introduced to the workplace without causing disruption and needing worker compliance. Also performance ratings are factored in to the motion times and so the subjective part of the study is eliminated. The timings should also be much more consistent than historical data for instance. Disadvantages include the fact that these times ignore the context of the job in which they are undertaken i.e. the timings are provided for the micromotion in isolation and not part of a range of movement. The sample is from a broad range of workers in different industries with different skill levels, which may lead to an unrepresentative time. Also the timings are only available for simple repetitious work which is becoming less common in industry.
		10.6.3.	Work Sampling Work Sampling is useful for analysing the increasing proportion of non-repetitive tasks that are performed in most jobs. It is a method for determining the proportion of time a worker or machine spends on various activities and as such can be very useful in job redesign and estimating levels of worker output. The basic steps in work sampling are indicated below :
			1.	Define the job activities All possible activities must be categorised for a particular job. e.g. “worker idle” and “worker busy” states could be used to define all possible activities.
			2.	Determine the number of observations in the work sampl  The accuracy of the proportion of time the worker is in a particular state is determined by the observation sample size. Assuming the sample is approximately normally distributed the sample size can be estimated using the following formula. n = (z/e)2 * p (1 - p) where n = sample size z = number of standard deviation from the mean for the       desired level of confidence e = the degree of allowable error in the sample estimate p= the estimated proportion of time spent on a work activity The accuracy of the estimated proportion p is usually expressed in terms of an allowable degree of error e (e.g. for a 2% degree of error, e = 0.02). The degree of confidence would normally be 95% (giving a z value of 1.96) or 99% (giving a z value of  2.58).
			3.	Determine the length of the sampling period There must be sufficient time in order for a random sample of the number of observations given by the equation in 2 to be collected. A random number generate can be used to generate the time between observations in order to achieve a random sample.
			4.	Conduct the work sampling study and record the observations Calculate the sample and calculate the proportion (p) by dividing the number of observations for a particular activity by the total number of observations.
			5.	Periodically re-compute the sample size required It may be that the actual proportion for an activity is different from the proportion used to calculate the sample size in step 2. Therefore as sampling progresses it is useful to re-compute the sample size based on the proportions actually observed.
	10.7.	Learning Curves Organisations have often used learning curves to predict the improvement in productivity that can occur as experience is gained of a process. Thus learning curves can give an organisation a method of measuring continuous improvement activities. If a firm can estimate the rate at which an operation time will decrease then it can predict the impact on cost and increase in effective capacity over time. The learning curve is based on the concept of when productivity doubles, the decrease in time per unit is the rate of the learning curve. Thus if the learning curve is at a rate of 85%, the second unit takes 85% of the time of the first unit, the fourth unit takes 85% of the second unit and the eighth unit takes 85% of the fourth and so on. Mathematically the learning curve is represented by the function y = ax-b where y = time to produce the xth unit a = hours required to produce the first unit x = number of units produced b= constant equal to -(ln p)/(ln 2)   where ln = log10 p = learning rate (e.g. 80% = 0.8) Thus for a 80% learning curve b = - (ln 0.8)/ ln(2) = -(-0.233)/ 0.693 = 0.322 Learning curves are usually applied to individual operators, but the concept can also be applied in a more aggregate sense, termed an experience or improvement curve, and applied to such areas as manufacturing system performance or cost estimating. Industrial sectors can also be shown to have different rates of learning. It should be noted that improvements along a learning curve do not just happen and the theory is most applicable to new product or process development where scope for improvement is greatest. In addition step changes can occur which can alter the rate of learning, such as organisational change, changes in technology or quality improvement programs. To ensure learning occurs the organisation must invest in factors such as research and development, advanced technology, people and continuous improvement efforts.