UNIVERSITI TEKNIKAL MALAYSIA MELAKA

Time Study Method Implementation In

Manufacturing Industry

Report submitted in accordance with the partial requirement of the Universiti

Teknikal Malaysia Melaka for the Bachelor of Manufacturing Engineering

(Manufacturing Process)

By

Nor Diana Hashim

Faculty of Manufacturing Engineering

May 2008

ABSTRACT

Time study is often referred to as work measurement and it involves the techniques

of establishing an allowed timed standard to perform a given task, with due

allowance for fatigue and for personal and unavoidable delays. Time study are used

for two main purposes in CTRM Aero Composites Sdn. Bhd., one for bidding new

projects and the other one is to monitor the production line. Each of the time study

techniques is applied under certain condition and the best technique for manual

production is the stopwatch time study because human performance is not consistent

from time to time. The stopwatch time study had been chosen for the case study

because 90 percents of the production in CTRM Aero Composites Sdn. Bhd. are

handled manually by man power. The aim of this case study is to find the suitable

rating factor and allowance for each process in order to conduct the stopwatch time

study for the panel produce by the CTRM Aero Composites Sdn. Bhd. and finally to

develope a time study database which will be used as a single source of reference by

the company.

Keywords: Time Study, Rating Factor, Allowances

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ABSTRAK

Kajian tentang masa atau juga selalu dirujuk sebagai pengukuran kerja adalah

mengenai lebihan masa yang dibenarkan dalam menjalankan sesuatu kerja

berdasarkan lebihan masa untuk keletihan, perkara peribadi dan perkara tertangguh.

Kajian tentang masa digunakan untuk dua tujuan utama di CTRM Aero Composites

Sdn. Bhd., yang pertama adalah untuk membida projek baru dan yang kedua untuk

mengawasi pengeluaran produk. Setiap teknik tersebut diaplikasikan dibawah

keadaan tertentu. Kajian tentang masa menggunakan jam randik telah dipilih untuk

menjalankan projek ini kerana 90 peratus produksi di CTRM Aero Composites Sdn.

Bhd. dilaksanakan secara manual dengan tenaga kerja manusia. Tujuan utama kajian

kes ini adalah untuk mendapatkan faktor kadar dan lebihan masa setiap proses bagi

menjalankan kajian tentang masa menggunakan jam randik untuk panel yang

dihasilkan oleh CTRM Aero Composites Sdn. Bhd. dan akhirnya membangunkan

suatu pangkalan data kajian tentang masa yang akan digunakan sebagai sumber yang

tunggal oleh syarikat tersebut.

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CHAPTER 1

INTRODUCTION

1.1 Background

As we approach the new millennium, with a widely expanded market and

manufacturing capability around the world, both the opportunities and the need for

technical competence are growing dramatically. According to Niebel (1993), ten years

ago the competition was centered in only a few industries - electronics and automotives

in particular. But today this competition is both industry wide and world wide. Each

department of these organizations is increasing the intensity of its cost reduction and

quality improvement effort in order to survive and expanding. Some companies have

even expanded their motion and time study method to nonmanufacturing activities with

the rise in the importance of indirect factory labor.

One of the oldest tools used by industrial engineers in work measurements is

time study and specifically stopwatch time study. Time study that originated by Taylor

and developed by Gilbreths was used mainly for determining time standards and motion

study. According to Rice (1977), over 89 percents of the companies that perform work

measurement used time study. The technologies are rapidly growing everyday but there

are still no tools that can replace time study method completely. They only invented

equipment that can improved the tools and made it users friendly. According to Niebel

(1993), computers produce standards from fundamental motion data up to 50 percents

faster than manual methods. The computers also provides a simple and convenient way

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to make time studies, monitor and measure machine and equipment performance, make

work sampling studies, and perform other data-gathering activities. Even though there

are many techniques and equipments to perform the time study, but basically the concept

is just the same.

In manufacturing industries, especially for industries that implement 90 percents

of manual production time study is very crucial. For example, manufacturing plant

management need time standards, even before production starts, to determine how many

people to hire, how many machines to buy, how fast to move conveyers, how to divide

work among employees, and how much the product will costs; after production starts, to

determine how much cost reduction will return, who works the hardest, and perhaps who

should earn more money; and after production finish, the data are used as reference for

bidding new projects and procurement. Time study can reduce and control costs,

improve working conditions and environment and motivate people.

Manufacturing management and engineers are prepared to design work stations,

develop efficient and effective work methods, establish time standards, balance

assembly lines, estimates labor costs, develop effective tooling, select proper equipment,

and lay out manufacturing facilities. However the most important thing is how to train

production workers in these skills and techniques so they can become motion and time

conscious. The manufacturing management and engineers only design and prepared the

skills but the production workers who are going to implement it in the operation. So the

objective of time study can only be achieved if the production workers are

knowledgeable about the time study concept.

1.2 Problem Statements

CTRM AC used Time Study for two main purposes, one for bidding new projects and

the other one is to monitor the manufacturing or production of current projects. The

current project needs to be monitor by using time study in order to control the cycle time

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and labor power of one project. Another point why time study suited with CTRM AC

because 90 percents of the production in this company is manual basis so there’s no

better tool to measure the work than time study because it include the rating factor and

allowances. In the mean time it also can be use as a tool for productivity improvement

and increase efficiency. Since time study is so important for the company, it had to be

done precisely with the element of allowance, rating factor and head count to produce a

standard time which can be used as reference to conclude the whole performance of

production.

1.3 Objectives of the Project

(i) To identify the suitable rating factors and allowances for the stopwatch

time study that suitable for manual production at CTRM AC.

(ii) To establishes cycle time from the current project on man hours and

machine hours by using time study method.

(iii) To develop a time study database for the company by using Microsoft

Excel 2003 that will be use as a single source reference of standard data

information.

1.4 Scopes of Project

To ensure the objectives will successfully achieve, there are several element that need to

be followed as well:

(i) Conduct a time study by including cycle time from observation with the

allowance and rating factors to produce standard time.

(ii) The study was undertaken by using stopwatch time study technique.

(iii) The research is going to be done at CTRM Aero Composites for project

Goodrich V2500 (Torque Ring Cone Fairing Panel).

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CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

Time study is one of the oldest fundamental method ever used whose results in increased

productivity. Since the research are focus on the time study from all aspects, so the

history of the time study must be analysis and how it develop into the most useful tools

in manufacturing industry. Most of the source used for the studied comes from a reliable

and trustworthy source. The sources include articles, journals and books. There actually

more than one technique mention in this thesis but the research only focuses on one

method only. The method is stopwatch time study and it had been chosen because it

suitable with the industry in the case studies.

Any of the work-measurement techniques represent a better way to establish fair

production standard. All of these techniques are based on facts. All establish an allowed

time standards for performing a given task, with due allowance for fatigue and for

personal and unavoidable delays. Accurately establish time standards make it possible to

produce more within a given plant, increasing the efficiency of the equipment and the

operating personnel. Poorly established standards, although better than no standards at

all, lead to high costs, labor dissension and possibly even the failure of the enterprise.

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2.2 Chronology of Time Study

The Table 2.1 showed the major milestone of time study in the industry according to

year and the persona that contribute to the evaluation of the time study technique. The

descriptions of the persona are based on the contribution towards the time study fields.

Table 2.1: Chronology of Time Study

No. Year Persona Contribution1 1760 Jean Rodolphe

Perronet, French engineer

Extensive time studies on the manufacture of No. 6 common pins and arrived at a standard of 494 per hour (2.0243 hrs/1000).

2 1820 Charles W. Babbage, an English economist

Conducted time studies on manufacture of No. 11 common pins. It has determined that one pound (5,546 pins) should be produced in 7, 6892 hours (1.3864 hrs. /1000).

3 1856-1915 Frederick W. Taylor

The first person to use a stopwatch to study work content and as such is called the father of time study. He accomplishes the four Principles of Scientific Management. Responsible for the following innovations stopwatch time study, high-speed steel tools, tool grinders, slide riles and functional-type organization. He emphasized the analytical and organizational aspect of work.

4 1853-1931 Harrington Emerson

He was the expert that was needed to make Scientific Management, the Taylor system, a household name and his experience proved that the use of efficient methods would lead to tremendous savings. Accounts of his work were never extensively published and no comprehensive biography exists but his work is best remembered as an example of how the creative engineer can find the tools to improve any operation.

5 1861-1919 Henry Laurence Gantt

He invented the task and bonus system or earned-hour plan. He also developed a technique for scheduling work and performance control system. Rather than penalizing the less proficient worker, he

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advocated a livable wage with a sizable bonus for performance over 100 percents. He also designed the antisubmarine tactics known as convoy zigzagging that permitted escort ships to protect the slow freighters.

6 1868-1924 and 1878-1972

Frank and Lilian Gilbreth

Develop method study technique like cyclograph, chronocyclographs, movie cameras, motion picture camera and a special clock called a microchronometer. They also study fatigue, monotony, transfer of skills and assisted the handicapped in becoming more mobile. Their systematic study of motion reduced costs greatly and founded a new profession of method analysis. The Gilbreths also developed flow diagrams, process chart, and operation chart. Also the apprentice on the 17 elementary subdivisions of motion, later engineers coined a short word therblig.

7 1900-1984 Ralph M. Barnes

His achievements included writing the longest published text on work measurement, a through description of the Gilbreths micro motion study, time study and the procedure for work sampling.

2.3 Definition of Time Study

According to Meyers (2002), time standards can be defined as “the time required to

produce a product at a work station with the following three conditions: (1) a qualified,

well-trained operator, (2) working at a normal pace, and (3) doing a specific task.” The

three conditions are discussed below:

(i) A Qualified, Well-Trained Operator

Experience is usually what makes a qualified, well-trained operator and

time on the job is our best indication of experience. The time required to

become qualified varies with the job and the person. The greatest mistake

ever made by new time study personnel is time-studying someone too soon.

A good rule of thumb is to start with a qualified, fully trained person and to

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give that person two weeks on the job prior to the time study. On new jobs

or tasks, predetermined time study systems are used. These standards seem

hard to achieve at first because the time are set for qualified, well-trained

operators.

(ii) Normal Pace

Only one time standards can be used for each job, even though individual

differences of operators cause different results. A normal pace is

comfortable for most people.

(iii) A Specific Task

It is a detail description of what must be accomplished. The description

should include the prescribed work method, material specification, the tools

and equipment being used, the positions of incoming and outgoing material

and additional requirement like safety, quality, housekeeping and

maintenance tasks.

Time study is usually referred to as work measurement and it involves the technique of

establishing an allowed time standard to perform a given task, based on measurement of

the work content of the prescribed method and with due allowance for fatigue, personal

or unavoidable delays. Establishes time values are a step in systematic procedure of

developing new work centers and improving methods in existing work centers.

Generally time study is used to determine the time required by a qualified and well-

trained person working at a normal pace to do a specified task. The result of time study

is the time that a person suited to the job and fully trained in the specific method. The

job needs to be performed if he or she works at a normal or standard tempo. This time is

called the standard time for operation.

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Time study is composed of four parts:

(i) Developing the preferred method

(ii) Standardizing the operation

(iii) Determining the time standard

(iv)Training the operator

2.4 Objectives of Time Study

The principle objectives of time study are to increase productivity and product reliability

and lower unit cost, thus allowing more quality goods or services to be produced for

more people. The ability to produce more for less will result in more jobs for more

people for a greater number of hours per year. Only through the intelligent application of

the principles of time study can producers of goods and services increase while at the

same time, the purchasing potential of all consumers grows. Through these principles

unemployment and relief rolls can be minimized, thus reducing the spiraling cost of

economic support to nonproducers.

(i) Developing the preferred system and method-usually with the lowest cost

(ii) Standardizing this system and method

(iii) Determining the time required by a qualified and properly trained person

working at a normal pace to do a specific task or operation

(iv) Assisting in training the worker in the preferred method

Corollaries that apply to the principle objective are to (Niebel, 1993):

(i) Minimize the time required to perform tasks.

(ii) Continually improve the quality and the reliability of products and services.

(iii) Conserve resource and minimize cost by specifying the most appropriate

direct and indirect materials for the production of goods and services.

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(iv) Produces with a concern for the availability of power.

(v) Maximize the safety, health and well-being of all employees.

(vi) Produces with an increasing concern to protect our environment.

(vii) Follow a humane program of management that result in job interest and

satisfaction for each employee

5.1 The Important and Uses of Time Study

Although time study originally had its greatest application in connection with wage

incentives, it and the other methods measuring work are now used for many other

purposes including (Barnes, 1980):

(i) Determining schedules and planning work

(ii) Determining standard costs and as an aid in preparing budgets

(iii) Estimating the costs of a product before manufacturing it. Such information

is of value in preparing bids and determining selling price.

(iv) Determining machine effectiveness, the number of machines which one

person can operate, and as an aid in balancing assembly lines and work

done on a conveyor.

(v) Determining time standards to be used as a basis for labor cost control.

2.5 Time Study Techniques

The Table 2.2 showed the summary of time study techniques that had been discussed by

five different sources. Most of the technique had a same method but differ by name. The

detail descriptions on the techniques are discussed below.

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Table 2.2: Time Study Techniques by Source

No. Source Time Study Techniques1 Barnes, (1980). • Standard Data

• Work Sampling• Predetermined Time Standard System (PTS)• Stopwatch Time Study

2 Niebel, (1993). • Stopwatch Time Study• Computerized Data Collection• Standard Data• Fundamental Motion Data• Work Sampling and Historical Data

3 Lawrences, (2000). • Time Study• Standard Data Systems• Predetermined Time Systems (PTS)• Work Sampling• Physiological Work Measurement• Labor Reporting

4 Meyers and Stewart,(2002).

• Predetermined Time Standard System(PTSS)• Stopwatch Time Study• Work Sampling• Standard Data• Expert Opinion and Historical Data

5 Niebel and Freivalds, (2003).

• Time Study• Standard Data and Formulas• Predetermine Time Systems• Work Sampling• Indirect and Expense Labor Standards

4.1 Time Study in Non-Manufacturing Area

Together with the rise in the importance of indirect factory, there has come

tremendous increase in office work. Some companies have expanded their motion and

time study activities to include the office; others have establishes a separate department

to study office methods and procedures. The use of paper work simplification, office

work measurement, systems and procedures analysis, and procedure analysis, and office

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mechanization, and the installation of data-processing equipment are some of the

approaches being utilized to increase productivity and reduce costs in offices.

Banks, mail orders houses, hospitals, department stores, and supermarket are

obtaining worthwhile results from the applications of principles of motion and time

study to their activities. Great strides are being made in simplifying work on farms, as

well as in various branches of the government and military.

2.6 Description on Time study Method

Predetermined time systems, standard data, work sampling and stopwatch time study are

used for measuring work and these five methods of time study had been widely used for

various productions in the industry (Meyers and Stewart, 2002). Each of the different

method had their own criteria and concept that must be followed. Not all suitable for any

production, so here is the description of each method:

(i) Predetermined time standards system

This technique is used during the planning phase of a new project of a new

product development. At this stage, only sketchy information is available,

and the technologist must visualize what is needed in the way of tools,

equipment, and work methods. The technologist would design a work

station for each step of the new product manufacturing plan. Each work

station would be designed; a motion pattern would be developed. Each

motion would motion would be measured, a time value would be assigned,

and the total of these time values would be the time standard. This time

standard would be used to determine the equipment, space, and people

needs of the new product and its selling price. Frank and Lillian Gilbreth

developed the basic philosophy of predetermined time motion systems.

There are 17 wok elements that are known as therbligs. Each element was

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reduced to a time table, and when totaled, a time standards for that set of

motion was determined.

Methods time measurement (MTM), MODular Assignment at

Predetermined TimeS (MODAPTS) and Work Factors are popular

predetermined time systems inspired by the Gilbreths’ work. PTSS was

developed from MTM and other predetermined systems for the expressed

reason to teach a system within a few hours. PTSS is a simplified and good

system but additional training is desirable.

(ii) Stopwatch time study

Taylor (1856-1915) had started using the stopwatch around 1880 for

studying work. This technique is a part of many union contracts with

manufacturing companies. Several types of stopwatches could be used:

(a) Snapback: in one hundredths of a minute.

(b) Continuous: in one hundredths of a minute.

(c) Three watch: continuous watches.

(d) Digital: in one thousandths of a minute.

(e) TMU (time-measured unit): in one hundred thousandths of an hour

(f) Computer: in one thousandths of a minute.

All but the TMU watch read in decimal minutes. The TMU watch reads in

decimal hours. Digital watches and the computer are much more accurate

and have memory functions that improve accuracy.

Two different time study procedures are:

(a) Continuous time study.

(b) Long-cycle time study.

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(iii) Work sampling

Work sampling is the same scientific process used in Nielsen ratings,

Gallup Polls, attitude surveys, and federal unemployment statistics. We

observe people working and draw conclusions. Everyone who has ever

worked with someone else has done work sampling. Supervisors using

informal work sampling are forming attitudes about employees all the time.

Industrial technologists can walk through a plant of 250 people one time

and count people who are working and those who are not working and

calculate the performance of that plant within ±10 percent. Industrial

engineering often starts their consulting proposal with such statistics.

Consultants expect to find 60 percent performance in plants without

standards but that is an average.

(iv)Standard data

Standard data should be the objective of every motion and time study

department. Standard data is the fastest and cheapest technique of setting

time standards and standard data can be more accurate and consistent than

any other technique of time study. Starting with many previously set time

standards, the industrial technologist tries to figure out what causes the time

to vary from one job to another on a specific machine or class of machine.

There are several ways of communicating the time standards to future

generations of factory workers, supervisors and engineers:

(a) Graph

(b) Table

(c) Worksheet

(d) Formula

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(v) Expert opinion time standards and historical data

An expert opinion time standard is an estimation of the time required to do

a specific job. This estimation is made by a person with great experience

base and is usually a supervisor but sometimes it could be specialist or

planner. The expert would estimate every job and maintain a blacklog of

work. The blacklog of work would give the department time to plan the

job, thereby performing the job more effectively. Historical data is an

accounting approach to expert opinion time standard systems. A record is

kept of how much time was used on each job. When new job comes along,

it is compared to a previous job standard. The problem with historical time

standards is that they do not reflect the time the job should have taken.

Inefficiency is built into such a system, but a bad standard is better than no

standard at all.

2.7 Time Study Equipments

The equipment needed for time study work consists of a timing device and an

observation board. The devices most commonly used for measuring work area (Barnes,

1980):

(i) Decimal stop watches and electronics timers

(ii) The motion picture camera and video equipment

(iii) Electronic data collector and computer

(iv) Electrical and mechanical time recorders

(v) Observation board

(vi) Speed indicator/tachometer

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2.8 Making The Time Study

The exact procedure used in making the time studies may vary somewhat, depending

upon the type of operation being studied and the application that is to be made of the

data obtained. These eight steps, however, are usually required to perform time study in

industries (Barnes, 1980):

(i) Secure and record information about the operation and operator being

studied

(ii) Divide the operation into elements and record a complete description of the

method

(iii) Observe and record the time taken by the operator

(iv) Determine the number of cycle to be timed

(v) Rate the operator’s performance

(vi) Check to make certain that a sufficient number of cycle have been timed

(vii) Determine the allowances

(viii) Determine the time standard for the operation

2.9 Introduction to Stopwatch Time Study

The actual conduct of a time study is both an art and a science. To ensure success,

analyst must be able to inspire confidence in, exercise judgment and develop a

personable approach to everyone with whom they come in contact. In addition, their

backgrounds and training should prepare them to understand thoroughly and perform he

various functions related to the study. These elements include selecting the operator,

analyzing the job and breaking it down into its elements, recording the elapsed elemental

values, performance rating the operation, assigning appropriate allowance and working

up the study itself. There are two standard ways to record time study data (Barnes,

1980). The use of either method is a matter of analyst preference or company practice.

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The job must be divided into elements before choosing the method. These two methods

are:

(i) The continuous method

The data collection of this method involves starting the stopwatch when the

study begins and allowing it to run, uninterrupted, until the study is

complete. At the conclusion of each element, the current reading, or the

elapse time, is recorded on the data sheet. The continuous method is also

better adapted to measuring and recording very short elements.

(ii) The snapback method

In this method, after the watch is read at breakpoint of each element. The

watch time is returned to zero. As the next element takes place, the time

increments from zero. A drawback to using the snapback method is the

time that elapses while the hand sweep hand returns to zero. The snapback

method is also better adapted to measuring and recording long elements.

2.10 Rating, Leveling and Normalizing

Rating is the process of adjusting the time taken by an individual operator to what could

be expected from a normal operator. The method was developed by Mundel and Danner

(1994), eliminates the difficulty of establishing a normal speed criterion for every type

of work. Rating is a matter of judgment on the part of the time study analyst, and

unfortunately there is no way to establish a time standard for an operation without

having the judgment of the analyst. Rating an operator includes four factors:

(i) Skills

The effect of skill is minimized by timing only people who are skilled.

Operators must be fully trained in their work classification before being

time-studied. Habits of motion patterns must be routine enough that the

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operator doesn’t have to think about what comes next and where everything

is located. Very skilled operators make a job look easy, and the industrial

technologist must let this skill affect the rating.

(ii) Consistency

Consistency is the greatest indication of skill. The operator is consistent

when he or she runs the elements of the job in the same time, cycle after

cycle. Consistency is used to determine the number of cycles. A consistent

operator needs to run only a few parts before the cycle time is known with

accuracy. The skill of the operator should be evident to the time study

technician, and the technician’s rating of the operator should be high.

(iii) Working Conditions

Working conditions can affect the performance of an operator. In the early

twentieth century, this was much more of a problem than it is today. The

way we account for poor working conditions today is to increase the

allowance. Working conditions are not part of modern rating.

(iv) Effort

Effort is the most important factor in rating. Effort is the operator’s speed

and/or tempo and is measured based on the normal operator working at 100

percents.

Psychology has been good to the time study technicians. The normal tendency of people

being watched is to speed up. Being watched makes people nervous, and nervous energy

is converted by the body into a faster tempo. The time study technician then gets a

frequent chance to rate over 100 percent. When an operator works at 120 percent, the

technologist can give the operator 20 percent more time so that an average person can do

the job.

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9.1 Rating Methods

There are three rating methods that are usually being implemented in the

manufacturing industry (Barnes, 1980). The rating factors are as below:

(i) Speed rating

Speed rating is a performance evaluation method that only considers the

rate of accomplishment of the work per unit time. In this method, the

observer measures the effectiveness of the operator against the concept of a

qualified operator doing the same work, and then assigns a percentage to

indicate the ratio of the observed performance to normal or standard

performance.

In the speed rating method, analyst first appraise the performance to

determine whether it is above or below normal before putting the

performance to in the precise position on the rating scale that correctly

evaluates the numerical difference between the standard and the

performance demonstrated. Thus, 100 percent is usually considered normal.

A rating of 110 percent indicates that the operator was performing at a

speed 10 percent greater than normal, and a rating of 90 percent would

mean that the operator was performing at a speed 90 percent of normal.

(ii) Synthetic rating

The synthetic rating procedure determines a performance factor for

representative effort elements of the work cycle by comparing actual

elemental observed times to times developed through fundamental motion

data. Morrow, (1946) had established the synthetic rating in an effort to

develop rating method that would not rely on the judgment of a time study

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observer and would give consistent result. Thus, the performance factor

may be expressed algebraically as:

P = (F / O) (2.1)

where: P = performance or rating factor

F = fundamental motion time

O = observed man elemental time for the elements us in F

(iii) Objective rating

The method had been developed by Mundel and Danner (1994), eliminates

the difficulty of establishing a normal speed criterion for every type of

work. This procedure establishes a single work assignment to which the

pace of all other jobs is compared. After the judgment of pace, a secondary

factor assigned to the other job indicates its relative difficulty. Factors

influencing the difficulty adjustment are:

(a) Amount of body used

(b) Foot pedals

(c) Bimanualess

(d) Eye-hand coordination

(e) Handling or sensory requirements

(f) Weight handled or resistance encountered

Numerical values, resulting from experiments have been assigned for a

range of each factor. The sum of the numerical values for each of the six

factors comprises the secondary adjustment. The rating (R) can thus be

expressed as follows:

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R = P × D (2.2)

where: R = Rating

P = Pace rating factor

D = Job difficulty adjustment factor

9.2 Rating Applications

The first and most important characteristic of any rating system is accuracy. Since the

majority of rating techniques rely on the judgment of the time study observer, perfect

consistency in rating is impossible.

A rating system that is simple, concise, easily explained, and keyed to well-established

benchmarks is more successful than a complex rating system requiring involved

adjusting factors and computational techniques that confuse the average shop employee.

The value of rating is written in the RF column of the time study form. The value of

normal time can be calculated by using rating performance from the formula below

(Niebel and Freivalds, 2003):

NT = OT × R / 100 (2.3)

where: OT = mean observed time

NT = normal time

R = performance rating

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2.11 Allowance

Allowances are extra time added to the normal time to make the time standard practical

and attainable. No manager or supervisor expects employees to work every minute of

the hour. Types of allowance (Barnes, 1980):

(i) Personal

Personal allowances is that time an employee is allowed for personal things

such as talking to friends about nonwork subjects, going to the toilet,

getting a drink, going to pray or any other operator-controlled reason for

not working. An appropriate amount of time has been defined as about 5

percent of the work day, or 24 minutes per day.

(ii) Fatigue

Fatigue allowance is the time an employee is allowed for recuperation from

fatigue. Fatigue allowance time is given to employees in the form of work

breaks, more commonly known as coffee breaks. Breaks occur at varying

intervals and are of varying duration, but all breaks are designed to allow

employees to recuperate from on-the-job fatigue. Most employees today

have very little physical drudgery involved with their jobs, but mental

fatigue is just tiring. If an employee uses less than ten pounds of effort

during the operation of his job, then five percent fatigue allowance is

normal. A five percent increase in fatigue allowance is given for every ten-

pound increase in exertion required of the employee.

The breaks are calculated into the fatigue allowance because the reporting

practice is to not report the time spent on breaks separately. Because lunch

time is punched out and not reported, it does not enter into the allowance

calculation. Allowance is for times when the employees is expected to

perform but can’t.

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(iii) Delay

Delay allowances are called unavoidable because they are out of the

operator’s control. Something happens to prevent the operator from

working. The reason must be known and the cost accounted for to develop

the cost justification. The operator’s performance must not be penalized for

problems out of his or her control. Three methods are available to account

for and to control unavoidable delays:

(a) Add delay allowances to the standard

(b) Time-study them and add them to the time standard

(c) Charge the time to an indirect charge

For example, if the operator agrees that 15 minutes per day is a good figure,

the technologist will calculate a delay allowance as follows:

(15 min clean-up) / (480 min/shift) = 3%

A three percent allowance will be added to the personal allowance of five

percent plus a fatigue allowance of five percent to produce a 13 percent

total allowance.

An unavoidable delay is a foreign element that cannot be anticipated will

require the operator to charge his or her time to indirect account.

Supervisors will be required to approve all indirect charges and the time

should be more than six minutes to be statistically significant. Anything

that cannot be live with is not supposed to be in the time standard because

it is difficult to get it out once it included.

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2.11.1Allowances Application

The fundamental purpose of all allowances is to add enough time to normal production

to enable the average worker to meet the standard when performing at standard

performance. There are two ways of applying allowances (Niebel and Freivalds, 2003).

The most common is to add a percentage of the productive time only. It is also

customary to express the allowance as a multiplier, so that the normal time (NT) can be

readily adjusted to the standard time (ST).

ST = NT / (1- allowance) (2.4)

where : ST = standard time

NT = normal time

2.12 Summary of the Category Research

The Table 2.3 showed the summary of the category research of time study that related to

manufacturing industry. The summary is an analysis of the journals that related to the

time study and it had been divided into each sub-topic and category. The description of

each category is provided for better understanding.

Table 2.3: Summary of the Category Research of Time Study related to

Manufacturing Industry.

SUB-TOPIC CATEGORY AUTHOR/S DESCRIPTION

Definition of assembly cycle

time.

Choi and Ip, 1999; Hushizaki, 1990.

Assembly cycle time is the period of active time from starting to finishing an assembly operation and the operator

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2.10.1Introduction of

Time Study

(robot/human) is expected to be able to perform the task within the specified cycle time.

Definition of cycle time.

Hult and Nichols, 1999.

Cycle time is defined as the time takes from initiation to complete of the purchasing process which is often considered one of the most important performance indicators.

Wetherbe, 1995.

Cycle time is defined as the duration of the supply chain process from initiation to completion.

Narasimhan and Jayaram, 1998; Wetherbe, 1995.

Cycle time is the duration of the period between the internal customer’s recognition of a need to the provision of a good and service to that customer.

Escorpizo and Moore, 2007.

The time available to do one transfer (pick then place) will be referred to as cycle time.

Patel et al., 1994.

The cycle time of a product consists of the actual time to process for each operation, the waiting time before each operation and the transfer time between operations

Definition of manufacturing

cycle time.

Ballard et al., 2003.

Manufacturing cycle time is the time it takes for a product to be transformed from raw material to finished product.

2.10.2Main elements in

Time Study.

Work measurementWilding and Newton, 1996.

Time-based companies measure the cycle times and lead times of all their key activities.

The elementGriffin, 1997. Time can be considered

as the equivalent of

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