Industrial Erg

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Course Learning Outcomes for Unit

Upon completion of this unit, students should be able to:

1. Describe characteristics of ergonomically designed workstations.

1.1 Describe the relationship between proper ergonomic design and employee workstations.

1.2 Identify areas where injuries can occur due to poor workstation design.

2. Examine human factors related to design criteria.

2.1 Identify how one’s height, weight, and other physical criteria affect worker interactions with

workstations.

Reading Assignment

Chapter 1:

Book Organization

Chapter 2:

The Basics of Ergonomics

Chapter 3:

Anthropometry

Unit Lesson

Hello, and welcome to Unit I. In this unit, we will cover some of the basics of ergonomics. You may be asking

yourself why you are studying ergonomics in an undergraduate occupational safety and health (OSH)

program and how ergonomics can help you in your future career as a safety professional. Hopefully, this will

be made clear as you move forward with this unit; you will find that ergonomics is an important aspect of OSH

and is frequently addressed by important OSH-related agencies and organizations that safety professionals

often turn to for information (National Institute for Occupational Safety and Health [NIOSH], n.d.; Occupational

Safety & Health Administration [OSHA], n.d.).

Certainly, human beings are amazing machines, but their bodies do have limits. Consider the following

scenario. You are sitting at your kitchen table or in the front seat of your company vehicle while reading and

studying the material for this course. You are knee-deep into learning about ergonomics when your back

begins to cramp up, or maybe you feel a knot in your neck. These daily aches and pains can be a real

nuisance and can significantly hinder one’s productivity, but how does this happen? You were just sitting

there for goodness sake! And now you are in pain for apparently no reason! Now, consider such incidents

occurring on a much larger scale such as a factory floor where the major muscle groups of many employees,

including the legs and back, may be required to remain somewhat motionless for extended periods of time.

This causes muscles to remain in a contracted, static position and limits blood flow through the muscles,

which can lead to complications (Bush, 2012).

The interaction of people with machinery has come to be known as ergonomics. Fortunately, it is possible to

discover a lot of the causes of our discomfort by analyzing man/machine interactions and applying the

science of ergonomics to help workers avoid uncomfortable postures and activities that might lead to

unnecessary strains and stressors. In the example above, the cause of soreness and pain from sitting in a

static position has been identified, and the problem can be easily alleviated by providing employees with an

opportunity to get up and move around from time to time. Indeed, requiring an individual to move around a bit

can even be incorporated into the job itself without the requirement of a rest break. A person who sits while

UNIT STUDY GUIDE

Introduction to Ergonomics

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Title soldering electronic components, for instance, may be required to get up every so often to ge t more parts for

the operation.

Now that we know a few things about ergonomics, let us consider how the field of study came into being. The

application of ergonomic solutions to address human work is not new and has been considered frequently

throughout history, even if it was not labeled as such. For instance, around 500 B.C. in the Greek civilization,

craftsmen started using ergonomics in the design of their tools (Stack, Ostrom, & W ilhelmsen, 2016).

Additionally, farmers toiling in the fields and working with animals making furrows for their future crops had to

think, “There has to be a better way.” And indeed, we see through history that technology in agriculture has

resulted in making job tasks associated with the growing of crops much more accommodating to the human

body. Please spend some time reviewing the history of ergonomics. It is interesting to learn about some of the

people who have helped to grow this field of study and the contributions they have made.

As you can see in reviewing the history of ergonomics, humans have continued to fit the job to the person.

This has been helpful for businesses in more than one way. For starters, having an ergonomically ideal

workstation can help to enhance productivity and, hence, profitability. If any of you have ever bent over the

hood of a car to replace a serpentine belt, change spark plugs, or fix a leak, you will understand why body

positioning is important. If you can do a job without feeling pain, then you will be able to perform the job longer

and will likely make fewer mistakes. Employee safety and health is clearly another important consideration. It

is important to know how the workers’ environment might affect their physical well -being. A loud, noisy

environment that requires a full day of repetitive, forceful movements while standing in awkward positions and

bending over to retrieve parts can result in some fairly serious occupational injuries and illnesses over time.

These injuries and illnesses, such as lower back pain, lower back injuries, damaged rotator cuffs in the

shoulder, carpal tunnel syndrome, tendinitis, and tenosynovitis, have come to be labeled as work-related

musculoskeletal disorders (W MSDs) (Stack, Ostrom, & W ilhelmsen, 2016).

In addition to enhancing productivity and employee safety, ergonomics can also be a benefit; properly

designed workstations can prevent financial devastation to a worker and his or her family. Consider a

situation where the main breadwinner working at a poultry plant sustains a case of carpal tun nel syndrome as

a result of repetitive, forceful movements over a period of years and can no longer do his or her job. It is

important to do what we can to prevent such occurrences not only to ensure profitability but also to prevent

the impact of injuries and illnesses sustained by employees.

The third chapter of your textbook discusses the idea of anthropometry, which deals with the measurement of

the human body. Humans obviously can differ a great deal with respect to body size, reach, gait, strength,

and even how fast they can run or how high they can jump. Consider a married couple: the husband is 6 feet

tall, and the wife is 5 feet tall. The couple owns a German sports car that makes automatic adjustments to the

driver’s seat, steering wheel, and side mirrors. The car is generally driven by the wife, who is much smaller

than the husband. W hen the husband gets in to drive the car after his wife has driven it, his head hits the door

frame, his knees and chest hit the steering wheel, and he cannot see out of the side mirrors before hitting the

button to activate the automatic adjustments. The opposite happens when the wife gets in the car after the

husband has driven it; she is swallowed up in the car and can barely even reach the wheel. This is just one

example of why it is important to consider human variability in the design of workstations.

The idea behind anthropometry is to design the work environment with consideration of the people who are

going to use that machine or tool. If we know that most men are between 65 inches and 75 inches in height,

we could build a machine based on those standards. But, what if a woman needs to use that machine? Most

women are between 55 inches and 65 inches in height. This needs to be considered. Therefore, when we are

making measurements of our employees, we have to take into account who is going to use the machine or

work at the workstation in question, and we also need to consider that it may be inappropriate to exclude

individuals from a given job due to laws related to social equality. Thus, it is not uncommon to have to factor

in adjustability and various accommodations to make workstations fit a wide variety of individuals.

As you read through Chapter 3, you will note that there are a lot of tables and graphs. Use them as a

reference, but understand the concept behind the 95th-percentile rule and the 5th-percentile rule. Think about

the safety constraints that are designed into our everyday world. Recently, there was a terrible example of a

failure of the percentile rule. The Cincinnati Zoo had a gorilla enclosure, and the safety features of the outside

enclosure were meant to keep everyone out of the enclosure (Ellis & Rose, 2016). These precautions did not

prevent a young child from being able to climb into the enclosure, bypassing the safety features.

Unfortunately, the gorilla had to be put down to save the child. Had you been the designer of the enclosure’s

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safety system, would you have designed it to meet only the 50th percentile or the 90th percentile? Even at

100%, was there still a chance that a child could breach the system and become exposed to the dangers of

the animal? This is just an example of the importance of considering anthropometry in relation to public

safety.

Obviously, ergonomics pertains to more than just the worker sitting at his or her office workstation and

possibly developing carpal tunnel syndrome from typing too much. There is much more to the subject . Read

some of the case studies found at the end of Chapter 3, and then consider the workers whom you interact

with and the environments they face. Consider ergonomic issues these individuals might encounter in

performing their jobs. Consider the work environment and ergonomics of the bus driver, the train operator, the

cab driver, the plumber who fixes your toilet, or the electrician who works on your stove. Each of these

professionals faces unique work environments that pose unique ergonomics -related challenges.

In closing, take a look at the summary for each chapter, and study the review questions. That is where your

unit assessment questions will come from. The answers are there for the taking; use your textbook as the

reference it is.

References

Bush, P. M. (2012). Ergonomics: Foundational principles, applications, and technologies. Boca Raton, FL:

CRC Press.

Ellis, R., & Rose, R. (2016). Cincinnati Zoo kills gorilla to save child who slipped into enclosure. Retrieved

from http://www.cnn.com/2016/05/28/us/zoo-kills-gorilla/

National Institute for Occupational Safety and Health. (n.d.). Ergonomics and musculoskeletal disorders.

Retrieved from http://www.cdc.gov/niosh/topics/ergonomics/

Occupational Safety & Health Administration. (n.d.). Prevention of musculoskeletal disorders in the workplace.

Retrieved from https://www.osha.gov/SLTC/ergonomics/index.html

Stack, T., Ostrom, L. T., & W ilhelmsen, C. A. (2016). Occupational ergonomics: A practical approach.

Hoboken, NJ: W iley.