Work - Work System - Productivity - Human Comfort, Safety & Health

Work System - Productivity - Human Comfort, Safety & Health

Content of Slides

Historical Figures Related to Work

Industrial Revolution (1770’s)

James Watt
steam engine

Henry Maudslay
screw-cutting lathe
(Factories)
Machines started to replace workers
Produce more quickly and accurately
Specialization of labor
Use of large numbers of unskilled labors who works long hours for low pay (including women & children)
Interchangeable parts manufacture

Eli Whitney ( )
produces muskets for the US government
Standard parts
Special tools, fixtures etc.
Unique products replaces custom-fabricate products
Mass production (assembly line)

Henry Ford ( )
Model T for less than $500 in 1916

Scientific management (late 1800s)

Frederick W. Taylor ( )

Father of scientific management
Elementary Rate Fixing Department (Later became industrial engineering department)
Time study
Differential piece rate system (Incentive system - productivity reward)

Frank ( ) & Lillian Gilbreth ( )

Father (mother) of motion study
All works are composed of basic motion elements (therbligs)
There is one best method to perform a certain task.
Cheaper by the Dozen
Motion study (finding the best method to perform a task)
Time study to establish work standards for a job
Use of standards in industry
Labor incentives (bonus payments for higher outputs)
Use of data collection, record keeping, cost accounting
The objective is to improve the (labor) productivity

Serves an important economic function in the global world of commerce
Creates opportunities for social interactions and friendships
Provides the products and services that sustain and improve our standard of living

Work is an activity in which one exerts physical and mental effort to accomplish a given task or perform a duty
Task or duty has some useful objective
Worker applies skills and knowledge for successful completion
The activity has commercial value
The worker is compensated

The Pyramidal Structure of Work

Work consists of tasks
Tasks consist of work elements
Work elements consist of basic motion elements

Task Time required = 30 seconds to several minutes
An amount of work that is assigned to a worker or for which a worker is responsible
Repetitive task – as in mass production
Time required = 30 seconds to several minutes
Non-repetitive task – performed periodically, infrequently, or only once
Time required usually much longer than for repetitive task

Work Element
A series of work activities that are logically grouped together because they have a unified function in the task
Example: assembling a component to a base part using several nuts and bolts
Required time = six seconds or longer

Basic Motion Elements Examples:

Reaching for an object
Grasping the object
Moving the object
Walking
Eye movement
A work element consists of multiple basic motion elements
Less than a second

Importance of Time in Business and Industry
New product introduction
Product cost (reduced time means reduced labor costs)
Delivery time
Overnight delivery
Competitive bidding (proposals should be submitted by a specific date)
Production scheduling (being on time)

Importance of Time in Work
Time is the most frequently used measure of work (not Newton-meter)
How many minutes or hours are required to perform a given task?
Most workers are paid by the time they work
Hourly wage rate
Salary
Time=Money
Workers must arrive at work on time
Otherwise his/her absence may handicap the rest of the team
Labor and staffing requirements computed in units of time
Aggregate unit

Work System Defined (manual, machine system buraya)
As a physical entity, a work system is a system consisting of humans, information, and equipment designed to perform useful work
Results of the useful work contributes to the production of a product or delivery of a service
Examples:
Worker operating a machine tool in a factory
An assembly line consists of a dozen of workers at separate work stations along a moving conveyor
Parcel service agent driving a delivery truck to make customer deliveries
Designer working at a CAD workstation
A receptionist answering incoming phone calls

Work System Defined
As a field of professional practice, work systems include:
Work methods - analysis and design of tasks and jobs involving human work activity
Operations analysis & methods engineering
Work measurement – analysis of a task to determine the time that should be allowed to perform the task
Time study
Product costs
Worker performance
Worker requirements
Standard time
How long it takes to accomplish a given work
(Time=Money)

Work System Defined
As a field of professional practice, work systems include (cont.)
Work management – organizational and administrative functions that must be accomplished to achieve high productivity and effective supervision of workers
Organizing workers
Motivating workers
Evaluating jobs
Evaluating performances
Compensating workers (labor wages)

Comparisons: Industries and Workers
It is convenient to group occupations into the following four groups although there are more types of occupations
Production workers
Making products: Manufacturing, construction, agriculture

Logistics workers:
Moving materials, products, people
Transportation, distribution, material handling

Service workers
Providing service, applying existing information knowledge, communicate
Banking, retail, government, health care

Knowledge workers
Creating knowledge, solving problems, managing
Management, engineering, legal, consulting, education

Comparison of Work Characteristics
Physical activities
Cognitive activities

Productivity Individual production or service operations
The level of output of a given process relative to the level of input (output/input)
Process can refer to
Individual production or service operations
Can be used in the context of a national economy
Productivity is an important metric in work systems because Improving productivity means
saving scarce natural and human made resources
worker compensation can be increased without increasing the costs of products and services they produce
Products and services at lower prices for consumers which improves standard of living

Labor Productivity
The most common productivity measure is labor productivity, defined by the following ratio:
LPR =
where LPR = labor productivity ratio, WU = work units of output, LH = labor hours of input
The definition of output depends on the process under consideration
Steel industry : ton
Automobile industry: number of cars
Labor hour (aggregate unit)
Makes it possible to make comparisons across different industries

Labor Factor in Productivity
Labor itself does not contribute much to improving productivity
More important factors:
Capital - substitution of machines for human labor
Investing an automated production m/c to replace a manually operated m/c
Technology - fundamental change in the way some activity or function is accomplished
It is more than using a m/c in place of a human worker
A technologically more developed m/c replaces the previous one.

Examples of Technology Changes
Horse-drawn carts
Steam locomotive
Telephone operator
Manually operated milling machine
Railroad trains
Diesel locomotive
Dial phone
Numerically controlled (NC) milling machine

 Increasing Productivity
Important to recognize important gains in productivity are more likely to be made
By the introduction of capital and technology in a work process
Than by attempting to get more work in less time out of the workers
For example, in construction industry, mortar in mixers pumped into molds rather than workers mixing by shovels

Measuring Productivity
Not as easy as it seems because of the following problems:
Nonhomogeneous output units (Polo vs Golf)
Multiple input factors
Labor, capital, technology, materials, energy
Productivity comparisons are not easy for:
Price and cost changes due to economic forces and these effect the worth of the output
If prices decrease but costs increase productivity may be less meaningful

Labor Productivity Index
Measure that compares output/input ratio from one year to the next
LPI =
where LPI = labor productivity index, LPRt = labor productivity ratio for period t, and LPRb = labor productivity ratio for base period

Three Categories of Work Systems
Manual work system
Worker performs one or more tasks without the aid of powered tools (e.g. hammers, screwdrivers, shovels)
Worker-machine system
Human worker operates powered equipment (e.g. a machine tool)
Physical effort (less)
Machine power(more)
Automated work system
Process performed without the direct participation of a human worker


Some Definitions
Work unit – the object that is processed by the work system
Workpiece being machined (production work)
Material being moved (logistics work)
Customer in a store (service work)
Product being designed (knowledge work)
Unit operations – tasks and processes that are treated as being independent of other work activities
As opposed to sequential operations (sequence of operations required to manufacture a product or deliver a service)

Manual Work Systems
Most basic form of work in which human body is used to accomplish some physical task without an external source of power
With or without hand tools
Even if hand tools are used, the power to operate them is derived from the strength and stamina of a human worker
Hairbrush vs hair dryer
Of course other human faculties are also required, such as hand-eye coordination and mental effort

Pure Manual Work
Involves only the physical and mental capabilities of the human worker without machines or tools.
Material handler moving cartons in a warehouse
Workers loading furniture into a moving van without the use of dollies
Dealer at a casino table dealing cards
Office worker filing documents
Assembly worker snap-fitting two parts together

Manual Work with Hand Tools
Manual tasks are commonly augmented by use of hand tools.
Tool is a device for making changes to objects (formally work units) such as cutting, grinding,striking, sequeezing
Scissor, screwdriver, shovel
Tools can also be used for measurement and/or analysis purposes
Workholder to grasp or poisiton work units
Machinist filing a part
Assembly worker using screwdriver
Painter using paintbrush to paint door trim
QC inspector using micrometer to measure the diameter of a shaft
Material handling worker using a dolly to move furniture
Office worker writing with a pen

Repetitive vs. Nonrepetitive Tasks
Work cycle is relatively short (usually a few minutes or less)
High degree of similarity from one cycle to the next
Nonrepetitive Task
Work cycle takes a long time
Work cycles are not similar
In either case, the task can be divided into work elements that consist of logical groupings of motions

Ud. 8.11.2024

Pub. 24.9.2019