| Ergonomics and
the Aging Workforce |
Ronald J Lott Ph.D, CPE
|
Introduction
1. As ergonomic practitioners
(ergonomists) are we holistic in considering all possible ergonomic
risk factors during evaluations and assessments?
2. As ergonomic practitioners (ergonomists) do we only consider the
usually recognized ergonomic risk factors, i.e. repetition, frequency,
forces, posture and heavy lifting?
3. As ergonomic practitioners (ergonomists) are we familiar enough
with the non-worksite risk factors that may contribute to ergonomic
related injuries and illnesses?
4. As ergonomic practitioners (ergonomists) do we thoroughly consider
that the average age of the American workforce has been over 40 years
of age for over a decade due to the “becoming of age” of the Baby
Boomers, and that there are non-occupational age related medical
disorders that directly contribute to the occurrence of muscular
skeletal medical disorders?
Today, most manufacturing facilities find that most of their employees
are over 50 years of age. Now with lay-offs, with the more senior
employees remaining, will that average increase—probably.
An aged workforce provides challenges in devising and maintaining
health and safety programs. This relates to the health status of
workers simply because of their age and the non-occupational related
medical disorders affecting their ability to tolerate exposures to
workplace hazards. As such, it is possible, because of these
non-occupational medical disorders, that injuries or illnesses occur,
which are designated as being caused by the hazards in the workplace
when in reality, the cause of many may be secondary to pre-existing
non-occupational medical disorders.
Statistics indicate that the general population from which the
workforce is selected has a number of age related, non-occupational
medical disorders that may directly contribute to the risk factors for
ergonomic related disorders. Some of these include:
- More than 8 percent of the general population has Diabetes
Mellitus a disorder which interferes with use of glucose;
- With age the Basal Metabolic Rate decreases
- One in three adult men and women has some form of CVD Disease (CHD),
21.2 percent have hypertension and 2.5 percent have had a stroke.
- Among blacks, 9.6 percent have heart disease, 5.2 percent have
CHD, 29.2 percent have hypertension and 3.2 percent have had a
stroke.
- Among Hispanics, 9.2 percent have heart disease, 6.0 percent
have CHD, 19.6 percent have hypertension and 2.8 percent have had a
stroke.
This provides a challenge for the health and safety manager, and
ergonomists since the Health Insurance Portability and Accountability
Act of 1996 (HIPAA) prohibits inquiries about a worker’s medical conditions except by authorized personnel. However,
there are methods to protect workers without actually knowing an
individual’s medical conditions. This can be accomplished with a
viable system of better communication between supporting medical
personnel and the facility’s safety & health personnel. Such
communication requires that the ergonomic practitioner be familiar
with certain non-occupational medical disorders in order to provide
medical personnel appropriate information about workplace risk factors
that may relate to these disorders. Since their limitations related to HIPAA are less, if sufficient information is provided, better
decisions concerning the actual causes and methods of prevention can
be made. To make the assumption that medical personnel always have an
index of suspicion concerning the full spectrum of the specifics of
workplace hazards is not sufficient.
Communicating with Medical Support Personnel
The repetitious use of muscles and tendons, used frequently, requiring
degrees of force, in awkward postures under certain environmental
conditions requires the expenditure of energy. As such, one of the
four (4) recognized sciences of ergonomics is Physiology in
consideration of the consumption of energy. Energy consumption in the
human body is dependent upon the availability of Oxygen and Glucose as
well as the Metabolic Rate, and the health of the systems responsible
for delivery of blood to body.
Krebb Cycle or Citrus Acid Cycle
The Krebb Cycle is the physiological mechanism which produces energy
for use by cells from the hydrolysis of adenosine triphosphate (ATP)
to adenosine diphosphate (ADP) and phosphoric acid (Pi), which
releases energy. This process includes the availability of oxygen
through the respiratory tract and glucose, primarily through the
gastrointestinal tract. These together produce ATP or energy.
Certain non-occupational medical disorders such as
Type 1 and Type 2 Diabetes Mellitus (DM) can complicate this process
of energy production and availability to the cells of muscles. 8% of
the general population has DM.
If the proper information is provided to
medical personnel concerning the stresses of a job, the greater the
index of suspicion they will have to consider the contribution of
non-occupational medical disorders and that relationship to the onset
of the illness or injury. As such more thorough medical evaluation and
histories are likely to be conducted.
Basal Metabolic Rate
The basal metabolic rate, or BMR, is the minimum calorific requirement
needed to sustain life in a resting individual. Thyroxin, produced by
the thyroid gland is a key BMR-regulator which speeds up the metabolic
activity of the body.
BMR reduces with age. After 20 years, it drops about 2 per cent, per
decade.
The type and amount of activity, with consideration of the
environmental temperature affect the metabolic rate. In addition,
disorders of the thyroid gland increase in an aged population.
The Harris-Benedict formula (BMR based on total body weight)
The Harris Benedict equation is a calorie formula using the factors of
height, weight, age, and sex to determine basal metabolic rate (BMR).
This makes it more accurate than determining calorie needs based on
total bodyweight alone. The only variable it does not take into
consideration is lean body mass. Therefore, this equation will be very
accurate in all but the extremely muscular (will underestimate caloric
needs) and the extremely obese (will overestimate caloric needs).
Men: BMR = 66 + (13.7 X wt in kg) + (5 X ht in cm) - (6.8 X
age in years)
Women: BMR = 655 + (9.6 X wt in kg) + (1.8 X ht in cm) - (4.7 X
age in years)
Note: 1 inch = 2.54 cm
1 kilogram = 2.2 lbs
If the proper information is provided to
medical personnel concerning the stresses of a job, the greater the
index of suspicion they will have to consider the contribution of
non-occupational medical disorders and that relationship to the onset
of the illness or injury. As such more thorough medical evaluation and
histories are likely to be conducted.
Cardio-Vascular Disease
As previously indicated, statistics indicate that the general
population from which the workforce is selected has a number of age
related, non-occupational medical disorders that may directly
contribute to the risk factors for ergonomic related disorders. Some
of these include:
-
More than 8 percent of the general population has
Diabetes Mellitus a disorder which interferes with use of glucose;
-
With age the Basal Metabolic Rate decreases
-
Over 147,000 Americans killed by Cardio Vascular
Disease (CVD) in 2004 were under age 65.
-
One in three adult men and women has some form of
CVD Disease (CHD), 21.2 percent have hypertension and 2.5 percent
have had a stroke. The cardio-vascular system is made up of
arteries, veins and the heart which delivers oxygen, glucose, and
other nutrients to organs such as muscles, tendons, and ligaments.
Certain anatomical changes to the arteries such as atherosclerosis and
arteriosclerosis interfere with this delivery. A major cause of these
disorders is related to the levels of lipids (cholesterol) in the
blood. Elevations of cholesterol are common with aging. Often workers
are under treatment for these conditions to include hypertension (high
blood), hyperlipoprotenemia (high cholesterol), high triglycerides, or
other cardio-vascular disorders such as arrhythmias (with medications
or artificial pace makers), stints in blood vessels of the heart, etc.
Any or all of these disorders may be a risk factor as a contributing
factor in the development of an ergonomic related medical disorder.
If the proper information is provided to
medical personnel concerning the stresses of a job, the greater the
index of suspicion they will have to consider the contribution of
non-occupational medical disorders and that relationship to the onset
of the illness or injury. As such more thorough medical evaluation and
histories are likely to be conducted.
Pulmonary Disease
One of the primary components of energy production in the human body
is oxygen (O2). Normal atmospheric O2 is 21% which is diffused through
the walls of the alveolar sacs in the lungs as a function of
concentration and pressure with the exchange of CO2. Changes in lung
tissue over time due to environmental exposures, and particularly in
the case of a smoker, occur which may interfere with the transfer of
these gases.
Since O2 is a primary component of the production of ATP (see Krebb
Cycle) for energy to muscles, interference with the availability of O2
subjects a worker to the risk of the development of ergonomic related
medical disorders.
If the proper information is provided to
medical personnel concerning the stresses of a job, the greater the
index of suspicion they will have to consider the contribution of
non-occupational medical disorders and that relationship to the onset
of the illness or injury. As such more thorough medical evaluation and
histories are likely to be conducted.
Summary
The more orientation the ergonomic practitioner (ergonomist) has of,
not only the usual worksite ergonomic risk factors, but also those
non-occupational medical disorders related to age and the physiology
thereof, the more proficient we can be in protecting workers. With
this orientation our partners in the medical community will be more
proficient in not only the treatment and return to duty of injured
workers, but the prevention of illnesses or injuries in the evaluated
worker and others.
Feel free to call for an initiation consultation at no
charge.
Office—931-552-4655 (888-247-4655)
Mobile—931-624-4293
|
