Time Study for Garment Production

Time study is a work measurement technique commonly used by apparel engineers to determine the rate at which a specific operation is performed. The objective of a time study is to develop and check production standards.

An operation is studied by time analysts while a style is in production. Time studies are an appropriate method of work measurement for high-volume operations with a high degree of repetitiveness. They are frequently used to establish production standards for operations performed in a progressive bundle system.

1. Time Study Procedure:

The procedure for time study can best be described step-wise, which is self-explanatory.

1. Select Garment

At first garment has to be selected for time study which has not been studied before. A time study is conducted by analysts while a style is in production.

2. Identify operation

The garment is analyzed to identify the process or operation for study. A time study also requires a method description for the specific operation to be done. Time study may be conducted on a specific operation rather than a whole garment, which has not been previously studied or the method has been changed recently or there are any complaints regarding time standard.

3. Break the operation down into elements

To prepare a time study, analysts break the operation down into elements. Each element involves a group of motions with a definite beginning and end that can be identified and timed. Elements of the operation are listed in the left column of the time study sheet. Potential elements for a sewing operation may include

• Picking up and positioning parts
• Matching and aligning parts
• Positioning parts to the needle or presser foot
• Sewing
• Disposing of parts

Machine-controlled elements are separated from manually controlled elements on cycle machines because they are always constant.

4. Select operator

A qualified operator must be selected for study if more than one operator is doing the same task. The selected operator should have the necessary skill, experience, temperament, and knowledge about the purpose of the study.  So selection of workers for time study is a very important factor in the success of the study. If there is only one person on the job, there is no choice.

5. Record Cycle time

A time analyst records readings from a stopwatch or digital time board at the completion of each element. Times are recorded for each element for 10-20 cycles. A minimum of 10 cycles should be timed to provide a fair representation of the operation. The amount of lapsed time is averaged for each element. This is called observed time, which is the average amount of time that the analyst determined was used to complete each element.

6. Adjust Rating Factor

To level the observed time to what a normal operator could do, the operator’s performance is rated by the analyst. The speed at which the observed operator worked may be above or below the rate that a normal operator can perform. A rating below 100% reduces the time and above 100% increases the time allowed for an element to be completed. So it is necessary to adjust a rating factor with the observed time

Basic time is always constant as an observed rating is increased observed time decreases. The standard rating is 100, the observed rating may be below or above of standard rating. There are different systems used but they must be consistent; thus, analysts must be well-trained if time studies are to be fair and reliable. The performance rating which depends on the judgment of the analyst is the most difficult and controversial part of a time study.

7. Determine allowances

To get the standard time, a proper allowance must be added to include the nonproductive time that occurs as part of the production process. An allowance factor is a percentage of time added to the normal time including

• Machine allowances 
• Relaxation allowance
• Interference allowance
• Process allowance
• Contingency allowance
• Special allowance

8. Determine production standard

Production standard is a rate stated in standard allowed minutes (SAM) or standard minute value (SMV) that reflects the time required for a normal operator to complete one operation using a specific method. The production standard is also an indicator of how many times the operation can be completed in a given time. A total of the production standards of each style indicates the minimum throughput time to produce a specific style. 

SAM or SMV= Basic Time + Allowance

2. Objectives of production standard

Production standards are used in production planning to accomplish the following objectives

1. Production calculation
2. Efficiency calculation
3. Performance calculation
4. Line balancing
5. Load and capacity calculation
6. Adjustment of factory capacity
7. CM calculation

3. Time Study Equipment

The following equipment is needed for time study.

1. Timing Device

The stopwatch is the most widely used timing device used for time study, although an electronic timer is also sometimes used. The two perform the same function with the difference that an electronic timer can measure time to the second or third decimal of a second and can keep a large volume of time data in memory.

2. Time Study Observation Sheet 

It is a printed form with spaces provided for noting down the necessary information about the operation being studied, like name of operation, drawing number, name of the worker, name of time study person, and the date and place of study. Spaces are provided in the form for writing detailed descriptions of the process (element-wise), recorded time or stop-watch readings for each element of the process, performance rating(s) of an operator, and computation. A typical time study observation sheet is as below.

			Operator											Code
			Operation											Code
Code	Elements		Cycle											Avg.	Rat.	B/Time
			1	2	3	4	5	6	7	8	9	10	Total
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Size			Workplace Layout						Sketch of Parts					Total Std. Min
Style														Allowances
Fabric														SAM/ Pc.
Machine														SAM/ Dzn.
RPM														Dzn/ Day
SPI														Piece Rate
Analyst
Plant

3. Time Study Board

It is a lightweight board used for holding the observation sheet and stopwatch in position. It is of a size slightly larger than that of the observation sheet used. Generally, the watch is mounted at the center of the top edge or near the upper right-hand corner of the board. The board has a clamp to hold the observation sheet. During the time study, the board is held against the body and the upper left arm by the time study person in such a way that the watch could be operated by the thumb/index finger of the left hand. Watch readings are recorded on the observation sheet by the right hand.

4. Other Equipment

This includes a pencil, eraser, device like a tachometer for checking the speed, etc.

4. Advantages and disadvantages of Time study

Advantage

An advantage of time study compared to other work measurement techniques is the breakdown and analysis of the method before time measurement. Time studies measure actual performance; thus, they provide realistic data on the materials, equipment, and method being performed.

Disadvantages

Disadvantages are the time and training required for an analyst to become skilled in conducting time studies and the fact that operators have to be experienced in the operation before time studies can be done. Another disadvantage is the subjectivity of performance rating that must be done by the time analyst.