ENG M 501 Production and Operations Management Chapter 6A Job Design and Work Measurement Lecture 04a: 27 January 2009 John Doucette Dept. of Mechanical Engineering University of Alberta

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Introduction to Job Design Job designJob design is the function of specifying work activities in an organizational setting. –meet the requirements of the organization and its technology –satisfy the worker’s personal and individual requirements Job Structure Mental and physical consideration of workforce Tasks to be performed Geographical location of organization & work areas Time of day, sequence in the workflow or process Organizational rationale for the job Method of Performance Who?What?Where?When?Why?How?

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Behavioural Considerations in Work Design Focus on the interaction between technology and the work group –Task and skill variety an optimal variety is needed too much variety can be frustrating and inefficient for training too little can lead to boredom and fatigue –Feedback some means for informing employees quickly when they have achieved their targets –Task identity avoid overlapping between tasks –Task autonomy employees should be able to have some control over their work area

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Physical Considerations in Work Design Work physiologyWork physiology sets work-rest cycles according to the energy expended in various parts of the job. –the harder the work, the more the need for rest periods ErgonomicsErgonomics describes the study of the physical arrangement of the work space together with tools used to perform a task. –fit the work to the body rather than forcing the body to conform to the work.

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Study Methods worker at a fixed workplace production process worker interacting with other workers worker interacting with equipment Job Design 4 main activities to focus on

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Measurement Work measurementWork measurement is a process of analyzing jobs for the purpose of setting time standards Time study –Timing all tasks required for the job Work sampling –Random sampling of a worker’s activities

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Time Study normal timeThe normal time (NT) is the how long it should take an ordinary worker to complete the task: NT = UT x PR UT = observed performance time per unit PR = performance rating, which is a measure of how fast or efficient a worker is relative to what is considered normal. Also: NT = TW x PR # Units TW = total time worked

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Time Study (2) standard timeThe standard time (ST) is used to correct for potentially unavoidable work delays: ST = NT x (1 + allowances) Allowances = estimated percentage of time due to the delay Also: ST = ___NT___ 1 – allowances The second equation is actually better

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Time Study In-Class Example You want to determine the standard time for a job. The employee selected for the time study has produced 20 units of product in an 8 hour day. Your observations made the employee nervous and you estimate that the employee worked about 10 percent faster than what is a normal pace for the job. Allowances for the job represent 25 percent of the normal time. What are the normal and standard times for this job?

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Use inferences to make statements about work activity based on a random sampling of the activity Work sampling has three primary applications –Ratio Delays Determine activity-time percentage for workers or equipment –Performance Measurement Relates work time to output (performance index) –Time Standards How long does/should it take to perform each task?

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Procedure 1.Identify the specific activity or activities that are the main purpose of the study. 2.Estimate the proportion of time of the activity of interest to the total time. 3.State the desired accuracy. 4.Determine the specific times when each observations is to be made. 5.At two or three intervals during the study period, recompute the required sample size by using the data collected thus far. Adjust the number of observations if appropriate.

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Advantages Several work sampling studies may be conducted simultaneously The observer usually need not be a trained analyst No timing devices are required Work of a long cycle time may be studied with fewer observer hours Study duration is longer, so minimizes effects of short- period variations The study may be temporarily delayed at any time with little effect Because work sampling needs only instantaneous observations, the operator has less chance to influence the findings by changing work method

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Example A hospital wants to determine how much of its nurses’ time is spent on classic nursing duties (rather than other things like paperwork, etc.). We estimate that it’s probably somewhere around 60% but want to use work sampling over a period of 10 days (on shifts that run from 7:00 AM to 3:00 PM) to determine it within an error of 3%.

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Example (2) The first step is to look on table TN5.11 in your text book and determine how many observations we want.

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Example (3) Since we want observations in total, then we need ≈ 107 per day. Next, we assign random numbers to the eligible times: Time Random Numbers 7:00 – 7:59 AM :00 – 8:59 AM :00 – 9:59 AM :00 – 10:59 AM :00 – 11:59 AM :00 – 12:59 PM :00 – 1:59 PM :00 – 2:59 PM

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling Example (4) Finally, pick random numbers and match them with the times assigned to them. Using random numbers from the table in Appendix B: NumberTime :31 PM 55511:55 AM :48 PM :26 AM 954- ……

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Work Sampling In-Class Problem Your best guess is that one particular task of a complex operation takes approximately 5% of the operation’s total time. However, you’re not sure, and decide to establish a more accurate time standard using work sampling. You have someone available from 8:00 AM to 12:00 noon for the next 12 weeks (i.e., 60 working days). You want an absolute error of no more than 2.5%. –Calculate the number of observations per day. –Determine the sampling schedule for the first day.

John Doucette Dept. of Mechanical Engineering Lecture 04a, Chapter 6A: 27 January ENG M 501 – Production and Operations Management Financial Compensation and Incentive Plans Basic Compensation Systems –Hourly pay –Salary –Piece rate –Commission Individual and small-group incentive plans –Output measures –Quality measures –Pay for knowledge Organization-wide incentive plans –Profit-sharing –Gain-sharing