Learning Objectives:

• Learn various techniques for measuring time, including direct observation, work sampling, and predetermined time standards.
• Recognize the diverse applications of time study in process improvement, workload analysis, labor cost estimation, and production planning.

Time study provides standard time, which is the amount of time it takes workers to complete a job in a standard way. A good estimate requires standard times for various jobs.

1. Labor, machinery and equipment requirements
2. Daily, weekly or monthly material requirements
3. Cost of production per unit as an input to improve manufacturing or purchasing decisions
4. Work budget
5. Worker Efficiency and Incentive Payments.

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Solved Example: 9058-01

Time study is carried out by:

A. Finding all significant regarding the job, work, place, machine tool, etc

B. Breaking up each operation into small elements, which can be measured accurately

C. Observing and recording the time taken by the operator for an operation

D. All the above

Correct Answer: B

Solved Example: 9058-02

Time study in industries is performed to:

A. Improve efficiency of workers

B. Set the time standard

C. Simplify the work method

D. Measure time variation in the job

Correct Answer: D

Solved Example: 9058-03

Time study is:

A. The appraisal, in terms of time, of the value of work involving human effort

B. Machine setting time

C. Time taken by workers to do a job

D. Method of fixing time for workers

Correct Answer: A

Solved Example: 9058-04

Time study is carried out to determine the time required to complete job by:

A. A slow worker

B. A fast worker

C. An average worker

D. An apprentice

Correct Answer: C

Solved Example: 9058-05

In time study, the rating factor is applied to determine:

A. Standard time of a job

B. Merit rating of the worker

C. Fixation of incentive rate

D. Normal time of a worker

Correct Answer: C

Learning Objectives:

• Define predetermined time systems (PTS) and their role in work measurement and productivity improvement.
• Recognize the principles, objectives, and benefits of using PTS in industrial engineering and operations management.
• Explore common types of predetermined time systems, including Methods-Time Measurement (MTM), MODAPTS (Modular Arrangement of Predetermined Time Standards), MOST (Maynard Operation Sequence Technique), and Predetermined Motion Time Systems (PMTS).
• Understand the characteristics, applications, and suitability of each PTS method for different types of work and industries.

• Predetermined Motion Time Systems (PMTS) is a work measurement technique whereby time established for basic human motions are used to build up the time for a job at a defined level of performance.
• PMTS also called predetermined Time System (PTS), is a database of basic motion elements and their associated normal time values, together with a set of procedures for applying the data to analyze manual tasks and establish standard times for the tasks.
• They include motions such as reach, grasp, move and release.

• One time is indicated for a given motion, irrespective of where such motion is performed.
• It avoids both ratings and direct observations, can lead to more reliability in setting standard times.
• PMT systems are not too difficult to apply and can be less time consuming than other methods.

Solved Example: 9059-01

A technique of Work measurement in which times established for basic human motions are used to build up the time for a job at the defined level of performance is called:

A. Work sampling

B. Time study

C. Predetermined motion time study

D. Analytical estimating

Correct Answer: C

Solved Example: 9059-02

Which one of the following is not a technique under Predetermined Motion Time System (PMTS)?

A. Work factor

B. Synthetic data

C. Stopwatch time study

D. MTM

Correct Answer: C

Solved Example: 9059-03

P.M.T.S. (Predetermined Motion Time Systems) include:

A. M.T.M. (Method Time Measurement)

B. W.F.S. (Work Factor Systems)

C. B.M.T.S. (Basic Motion Time Study)

D. All of these

Correct Answer: D

Learning Objectives:

• Learn various techniques for collecting work sampling data, including random and systematic sampling methods.
• Explore statistical techniques used in work sampling analysis, including confidence intervals and sample size determination.
• Recognize the limitations of work sampling, including the need for careful sampling design and potential observer bias.

Applications of Work Sampling:

1. Activity and Delay Sampling
2. Performance Sampling
3. Work Measurement

1. Take a preliminary sample to obtain estimates of parameter values.
2. Compute the sample size required.
3. Prepare a schedule for random observations at appropriate times.
4. Observe and record worker activites.
5. Determine how workers spend their time.

• Less expensive than time study
• Observers need little training
• Studies can be delayed or interrupted with little impact on results
• Worker has little chance to affect results
• Less intrusive

• Does not divide work elements as completely as time study
• Can yield biased results if observer does not follow random pattern.
• Less accurate, especially when job element times are short.

Solved Example: 9057-01

The error estimate (e) in work sampling varies with sample size (n) as:

A. $e \propto \dfrac{1}{n}$

B. $e \propto \frac{1}{{\sqrt n }}$

C. $e \propto \sqrt n$

D. $e \propto \frac{1}{{{n^2}}}$

Correct Answer: B

Solved Example: 9057-02

In a work sampling study of a worker, the information available are as follows:

• Total time of study: 30 hour,
• Number of items produced: 320,
• Total number of observations: 1000,
• Number of observations when worker is found working: 850 and
• Average performance rating: 105%.

A. 2.23

B. 4.19

C. 5.58

D. 6.60

Correct Answer: C

Solved Example: 9057-03

Percent idle time for men or machines is found by:

A. Work sampling

B. Time study

C. Method study

D. Work study

Correct Answer: A

Solved Example: 9057-04

Work sampling observations are taken on the basis of

A. Detailed calculations

B. Convenience

C. Table of random numbers

D. Past experience

Correct Answer: C

Solved Example: 9057-05

Work sampling is applied for:

A. Estimation of the percentage utilization of machine tools

B. Estimating the percentage of the time consumed by various job activities

C. Finding out time standards, specially where the job is not repetitive and where time study by stop watch method is not possible

D. All of the above

Correct Answer: D

Solved Example: 9057-06

Pick up the incorrect statement about advantages of work sampling:

A. Permits a fine breakdown of activities and delays

B. Simultaneous study of many operators may be made by a single observer

C. Calculations are easier, method is economical and less time consuming

D. No time measuring devices are generally needed

Correct Answer: A

Allowances are the extra time over and beyond the regular/basic time that is given to complete the assignment. In order to account for personal delays, unavoidable delays, fatigue delays, etc., extra time is added to the scheduled time. Standard time is created by adding allowances to normal or basic time.

The standard time is the outcome of the time study. It refers to the amount of time needed to complete the task while using an operator who is completely certified, trained, operating at a regular pace, and putting forth average effort. Before doing a time study, some fundamental conditions must be met.

Solved Example: 9389-01

Standard time is defined as:

A. Normal time + allowance

B. Normal time + idle time

C. Normal time + idle time + allowance

D. None of these

Correct Answer: A