In the last unit, we reviewed how human factors can influence occupational injuries and
safety professionals think about human factors related to injuries and illnesses, it is very common
about human errors. In other words, what did the employee do wrong that contributed to or
caused the injury
or illness? In many cases, it is not human error that causes an injury or illness, but the interaction
employee with the physical environment of the workplace.
The interaction of workers and machines has always been a problem. Prior to the Industrial
America was primarily an agrarian society. A large percentage of agricultural output was from
farms. Work was performed with primitive tools and required great physical efforts. Although
musculoskeletal disorder (MSD) was not yet in use, we can imagine that many farmers suffered
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would be called an MSD. We do not know the extent of MSDs for this group of workers because
were not kept at that time.
With the start of the Industrial Revolution in the United States, an entirely new set of physical
introduced. Work started moving from the family farms to manufacturing facilities in towns and
in the early 1700s, there were many inventions that both improved the production of consumer
increased the physical stresses to the employees working in businesses to produce those goods.
Some of the early inventions that had a profound impact on production in America included the
(1712), the flying shuttle (7133), the spinning Jenny (1764), the circular saw (1780), the
(1784), the power loom (1785), the cotton gin (1794), the metal lathe (1797), the Fourdrinier
machine (used to
make paper; 1799), the typewriter (1829), and the sewing machine (1846) (Robin L, 2010).
inventions greatly increased the production of goods in America, they also increased the physical
workers and the consequent injuries and illnesses.
The field of ergonomics in America arose from this interaction of workers and machines.
Understand that the
concept of ergonomics is not a new concept. In fact, the term ergonomics was first used in 1857
philosophical narrative by a professor in Poland (Pandve, 2017). The term was not adopted by
the safety field
until the middle of the 20th century.
Today, we primarily view ergonomics and human factors engineering as a science dedicated to
MSDs. This was not always the case. Initially, the study of ergonomics and human factors was
improving production. This focus increased greatly during WWII as the United States needed to
materials much more quickly and efficiently. After WWII, the emphasis continued to be
primarily focused on
production. In fact. Henry Ford II delivered a speech at the annual meeting of the society of
engineers about the challenge of human factors and engineering to meet that challenge. From the
topic of the
speech, we might expect an emphasis on worker safety. However, if you read the speech, Mr.
Ford does not
mention worker safety once (Ford, 1946). Instead, his speech focuses on how addressing the
workers and machines can help increase production and reduce the costs of automobiles,
people to purchase automobiles and increasing profits for companies. The only mention of lost
work days had
nothing to do with injuries and illnesses, but dealt with lost days related to labor union strikes
and how the use
of human engineering might reduce the number of strikes. It is amazing to see one of the leading
in America at that time discuss ergonomics and not once mention the relationship to worker
health and safety.
Sometime after WWII, the focus of ergonomics and human factors engineering began to shift
production to worker safety. The costs associated with MSDs continued to increase. A report
from the Bureau
of Labor Statistics (BLS) (n.d.) reported that 582,340 lost work days could be attributed to MSDs
in 1999. This
represented 34.2% of all lost work days in the United States in 1999 (BLS, n.d.). A review of the
shows that the percentage of all lost work days that can be attributed to MSDs has increased
33.6% in 1992 to 34.2% in 1999. The direct costs were estimated to be $20 billion, with indirect
estimated to be another $80 billion (BLS, n.d.).
The Occupational Safety and Health Administration (OSHA) first became directly involved with
issues in 1983. The OSHA Training Institute published its first training course on ergonomics
that year. The
training program was updated to a video presentation in 1998 (OSHA, 1998). In 1986, OSHA
national emphasis program to reduce back injuries. The first OSHA citation for a
was issued in 1987 under the General Duty clause of the OSH Act. OSHA released a voluntary
guideline for the red meat industry in 1990, which was updated in 1992 (OSHA, 1993).
In 1991, the American Federation of Labor and Congress of Industrial Organizations (AFL/CIO)
and 30 other
unions requested that OSHA issue an emergency temporary standard for ergonomics because of
increasing numbers of MSDs (AFL/CIO, 2004). OSHA issued an advanced notice of proposed
June 1992. As you can see from the textbook, the final passage of the ergonomics standard was
political, and the standard was rescinded using the Congressional Review Act for the first time in
rescission also prohibited OSHA from issuing any new ergonomics standard (Goetsch, 2019).
The prohibition from Congress required OSHA to take a new approach to addressing ergonomic
issues in the
United States. OSHA’s current approach is to issue guidelines for industries with high risks for
currently has multiple guidelines for specific industries, including poultry processing facilities
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homes (OSHA, n.d.). Safety professionals in these industries need to become familiar with the
guidelines for their industry.
One reason human factors engineering is difficult is because of the complexity of workers. Most
and tools are designed for the “average” worker.
This means that a percentage of your workforce will
not fit the definition used to produce the tool or
machine they will be operating or using. Most safety
professionals understand an important variable in
reducing MSDs is for workers to perform operations
in a “neutral position.” Any task where a part of the
worker’s body is placed in an unnatural position
increases the risk of an MSD. Many hand tools are
now designed to attempt to place the hand into a
neutral position while performing certain tasks. A
good example would be newer powered
screwdrivers designed so the worker does not have
to twist his or her hand to an uncomfortable
position. The problem is that not all hands fit the
new tool the same, and it is typically not costeffective to fit every worker individually.
Because ergonomics issues are typically very
complex, ergonomics has developed into a
specialty field with ergonomic degrees being offered
at some institutes of higher learning and some
national certifications being offered by organizations. Safety professionals must decide how
much work they
want to perform on ergonomic issues before calling in ergonomic specialists. Sometimes, the
down to available funding from the employer, which may require you to perform investigations
recommend fixes that you are not comfortable with.
In some cases, you may not realize you have an ergonomics problem at your worksite.
workplace analysis as described in the textbook can assist you in determining if there is a
rates are commonly used to detect problems. Incidence rates represent the number of new cases
of an injury
or illness over a specified time period. You can use incident rates to track specific injuries and
including MSDs. An ongoing increase in the incidence rates of MSDs would indicate a problem
present. You can also compare your incidence rates for MSDs to the incidence rates for your
industry as a
When you determine that a problem is present, you must perform an investigation to help
that can help identify possible solutions. Most ergonomic investigations are performed using a
The textbook contains some examples of how to perform a task analysis. OSHA also has some
can be used to perform a task analysis.
In some cases, injuries and illnesses are either caused or exacerbated by stress in the workplace.
would be another example of a human factor that can lead to accidents. Unlike the human factors
discussed above, stress can be much more difficult to identify, measure, and control. Unlike
physical stress placed on a worker’s hand, measuring psychological stress is very subjective.
Many times, it is
difficult to get workers to participate in activities that help identify stress or in programs
designed to reduce
Some companies have started a program where all employees are lead through a series of
designed to reduce stress prior to the start of the work shift and sometimes at the lunch break.
The time spent
in the exercise costs the employer some in direct costs but is thought to reduce total costs with
productivity and safety over the long haul.
Sitting vs. Standing
Stationary vs. Moveable
Large vs. Small Demand for Strength
Good vs. Bad Vertical Work Area
Nonrepetitive vs. Repetitive Motion
Low vs. High Surface Contact
Factors associated with physical stress
(Goetsch, 2019, pp. 208-209)
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American Federation of Labor and Congress of Industrial Organizations. (2004). Chronology of
ergonomics standard and the business campaign against it. Bakery, Confectionery, Tobacco
and Grain Millers’ International Union.
Bureau of Labor Statistics. (n.d.). Survey of occupational injuries and illnesses. U.S. Department
Ford, H., II. (1946, February 15). The challenge of human engineering: Mass production, a tool
for raising the
standard of living. Vital Speeches of the Day, 12(9), 271–274.
Goetsch, D. L. (2019). Occupational safety and health for technologists, engineers, and managers
Occupational Safety and Health Administration. (n.d.). Ergonomics. United States Department of
Occupational Safety and Health Administration. (1993). Ergonomics program management
meatpacking plants (OSHA Publication No. 3 123). United States Department of Labor.
Occupational Safety and Health Administration. (1998). Ergonomic programs that work [Video].
Department of Labor. https://www.osha.gov/video/ergonomics/index.html
Pandve, H. T. (2017). Historical milestones of ergonomics: From ancient human to modern
human. Journal of
Ergonomics, 7(4), e169. https://www.omicsonline.org/open-access/historical-milestonesofergonomics-from-ancient-human-to-modernhuman-2165-7556-1000e169.pdf
Robin L. (2010, October 19). Important inventions of the Industrial Revolution. Bright Hub
In order to access the following resources, click the links below.
In this unit, we mentioned that some companies have implemented stretching programs prior to
the start of
work in an effort to reduce MSDs. The following article evaluated some of the stretching
program to see how
effective they are at reducing MSDs.
Choi, S. D., Rajendran, S., & Ahn, K. (2017, May). Stretch & flex programs: Effects on the
musculoskeletal disorders & injuries. Professional Safety, 62(5), 38–43. https://searchproquestcom.libraryresources.columbiasouthern.edu/docview/1900042510?accountid=33337
Human factors and human factors engineering have been issues for centuries. However, they
always been linked to worker safety. The following link is to a speech presented by Henry Ford
II shortly after
WWII. Read the speech and see where the emphasis for human factors engineering was placed at