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Work Measurements. Lab # 5. Outline. 1. Work Study. 2. Method Study. 3. Work Measurement. 4. Time Study. 5. Standard Time. Work Study. Work Study is a generic term for management services and system engineering techniques, used to investigate:
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Work Measurements Lab # 5
Outline 1. Work Study 2. Method Study 3. Work Measurement 4. Time Study 5. Standard Time Lab # 5: Work Measurements
Work Study • Work Study is a generic term for management services and system engineering techniques, used to investigate: • Methods of performing work (Method Study). • The time taken to do it (Work Measurement). Lab # 5: Work Measurements
Work Study (Cont.) Work Study Work Measurements Method Study Lab # 5: Work Measurements
System Relationships Process analysis Engineer workflows Design work station & information arrangements Method study Plant layout Jobs Time study Work breakdowns Incentive rewards standard times Lab # 5: Work Measurements
Method Study • Method study is a technique to reduce the work content mainly by eliminating unnecessary movements by workers, materials, or equipments. • However, even after that, there could be substantial unnecessary time taken for the process because of lack of management control or inaction of worker. • Method Study approaches and tools of Method Analyst: • Flow Diagrams & Process Charts etc. • Critical questioning techniques. Will be covered in the next lab Lab # 5: Work Measurements
Work Measurement • Work measurements (WM) are techniques used to establish the time for a qualified, motivated worker to carry out a task at a defined rate of working. • Work measurement used to determine the standard number of minutes taht aqualified properly trained, and experienced person should take to perform a specific task or operation when working at a normal pace. • Work measurement is concerned with investigating, reducing and eliminating ineffective time, whatever may be the cause. • In practice, proving existence of the ineffective time is the most difficult task. Lab # 5: Work Measurements
Work Measurement (Cont.) • WM is also used to set standard times to carry out the work, so that any ineffective time is not included later. • Any addition the standard time would show up as excess time and thus can be brought to attention. Lab # 5: Work Measurements
Techniques for WM • Two alternative method: • Direct work measurement: • Time study: “the most widely used” • work sampling: Determines the proportion of time a worker spends on activities • Indirect work measurement (indirect method not on the task) with standard times are measured by standard data and formulation. • Synthesis from standard data. • Pre-determined motion time system. • Estimating. • Analytical estimating. • Comparative estimating. Lab # 5: Work Measurements
Purpose of WM • Work Measurement Purposes may be: • To reveal the nature and extent of ineffective time, from whatever cause. • So that action can be taken to eliminate it; and then, • To set standards of performance that are attainable only if all avoidable ineffective time is eliminated and work is performed by the best method available Lab # 5: Work Measurements
Applications of WM • To compare the efficiency of alternative methods. Other conditions being equal, the method which takes the least time will be the best method. • To balance the work of members of teams, in association with the multiple activity charts, so that, as far as possible, each member has tasks taking an equal time. • To determine, in association with man and machine multiple activity charts, the number of machines a worker can run. Lab # 5: Work Measurements
Time Study • Time Study: is the development of a standard time by observing a task and analyzing it with the use of a stopwatch • Time Study includes: • Establishment of standard times - management knowledge • Rating operator performance - criteria for appraisal • Gathering information to calculate production capabilities & data for capacity planning. • Defining work content of finished goods and services e.g. for charging & estimating. Lab # 5: Work Measurements
Time Study Before Time Studies After Time Studies Lab # 5: Work Measurements
Overview of Time Study 1. Secure and record information about the operation and operator being studied. 2. Orient the supervisor and the workers. 3. Improve the work methods. 4. Break the task into elements and record. 5. Observe and record the time taken by the operator. 6. Determine the number of cycles to be timed. 7. Rate the operator’s performance. Lab # 5: Work Measurements
Overview (cont.) 8. Check to make certain that a sufficient number of cycles have been recorded. 9. Determine the allowances. 10. Determine the time standard for the operation. 11. Check and debug the standards with audits. 12. Implement with recall review in one month. Lab # 5: Work Measurements
Reasons for Element Breakdown • Data is more readily reusable when each element is described separately, esp. beginning and ending points. • Standard (estimated) time values may be determined. • Individual elements may be excessively short (e.g., inspection), or too long. These can be picked out more easily in element form. • This allows for separate performance ratings for each. Lab # 5: Work Measurements
Taking and Recording of Data • Continuous timing - records readings at the end of each element as watch runs • Repetitive timing - after recording, watch is snapped back to zero at the end of each element • Multiple watches - connected by a lever; one runs, another is stopped, another set to go • Electronic watch - may continue in “split” mode Lab # 5: Work Measurements
Stopwatch Time Study Basic Steps • Establish standard job method • Break down job into elements • Study job • Rate worker’s performance (RF) • Compute average time (t) Lab # 5: Work Measurements
Standard time • Standard time: The amount of time it should take a qualified worker to complete a specific task, working at a sustainable rate, using given methods, tools and equipment, raw materials, and workplace arrangement. Lab # 5: Work Measurements
Uses of Time Standards To provide information on which the planning and scheduling of production can be based, including the plant and labor requirements for carrying out the program of work and utilization of resources. To provide information on which estimates for tenders, selling prices and delivery promises can be based. To set standards of machine utilization and labor performance which can be used for incentive scheme. To provide information for labor-cost control and to enable standard costs to be fixed and maintained. January 6, 2020 Lab # 5: Work Measurements 20
Standard Time (Cont.) • Two basic approaches to defining standard time. • Bottom-up • Starts with a basic measurement of time, adjusts for operator pace, and then allows for fatigue, personal needs, and delays. • Top-down • used in many labor contracts, and it normally defines standard time as that time under which a qualified employee working under usual conditions can make an incentive pay (specified) percent above base pay. Lab # 5: Work Measurements
Standard Time (Cont.) • Normal Time. • The time required for an average, trained operator to perform a task under usual working conditions and working at a normal pace. (It does not include allowances for personal needs and delays that would be necessary if the task were done all 8 hours.) • Normal Pace. • The pace of an average, trained, and conscientious operator working over an 8-hour day. • Actual Time. • The observed time required for an operator to perform a task. • Allowances. • The amount of time added to the normal time to provide for personal needs, unavoidable delays, and fatigue. Lab # 5: Work Measurements
Doing Time Study • When making a time study several decisions are made to assure desired results: • # of observations to make • Desired level of accuracy • Desired level of confidence for the estimated standard time • Desired accuracy level is typically expressed as a % of the mean observed times. Lab # 5: Work Measurements
Doing Time Study (cont.) • The normal time (NT) is the mean observed time multiplied by the Performance Rating Factor (PRF) • The PRF is a subjective estimate of a worker’s pace relative to a normal work pace. • The Performance Rating is usually expressed in decimal form in these formulas. So a person working 10% faster than normal would have a Performance Rating of 1.10 or 110% of normal time. Working 10% slower, 0.90 or 90% of normal. • The frequency of occurrence (F) is how often the element must be done each cycle. Lab # 5: Work Measurements
Doing Time Study (cont.) • The allowance factor (AF) is the amount of time allowed for personal, fatigue, and unavoidable delays. • Average observed time = Sum of times recorded to perform each element / # of observations • NT = Average observed time x PRF x F • ST = NT ( 1+ AF) Lab # 5: Work Measurements
Allowances • Personal time allowance - 4% - 7% of total time - use of restroom, water fountain, etc. • Delay allowance - based upon actual delays that occur • Fatigue allowance - to compensate for physical or mental strain, noise level, tediousness, heat and humidity, assumption of an abnormal position, etc. Lab # 5: Work Measurements
Normal Time vs. Standard Time Standard time is the total time in which a job should be completed at standard performance. Normal Time Rest Pers. Need Delay Standard Time Lab # 5: Work Measurements
Determining Labor Standards Performance Rating Allowance Fraction Observed Time Normal Time Standard Time Lab # 5: Work Measurements
Example • Allowance Factor =15% • Delete unusual or nonrecurring observations (marked with *) • 21 in job A , 5 in Job C • Compute average times for each element • Average time of job A = (8+10+9+11)/4 = 9.5 min. • Average time of job B= (2+3+2+1+3)/5 = 2.2 min. • Average time of job C= (2+1+2+1)/4 = 1.5 min. Lab # 5: Work Measurements
Example 1 (cont.) • Compute the normal time for each element • NT = Average observed time x PRF x F • NT of job A = 9.5 x 0.9 x 1 = 8.55min • NT of job B = 2.2 x 0.85 x 1= 1.87 min • NT of job C = 1.5 x 0.94 x 1 = 1.41 min • Total Normal Time = 8.55+1.87+1.41 = 11.83 min • Standard Time = NT ( 1+ AF) • or ST =11.83 (1+0.15) = 13.6 min Lab # 5: Work Measurements
Questions • Reconnecting the cables of the computer case. • Compute the standard time of the process using 10% allowance. Lab # 5: Work Measurements
Thank You Lab # 5: Work Measurements