Surgeon General's Confimnce on Agricultural Sai%y and Heat&
FARMSAFE 2000 o A National Coalition for Local Action
Conmned by the National lnsthte rbr Occupational Safety and HeaM
April 30 - May 3, 1991. Des Moines, Iowa

MACHINE DESIGN

       By Sverker Hogliiltd, M.D.
Director, Swedish Farmers Safety and Preventive Health Association
           Stockhoim, Sweden

Dr. David S. Pratt: it is a distinct pleasure to introduce now, Dr. Sverker Hogiiind. Dr. Hogiijnd grew
up on a farm in northern Sweden, completed his education as a physician, and went on to obtain
specialty training-first in hematology and then in internal medicine and occupational health. He is
currently an Associate Professor at the institute in Stockhoim, and he has worked actively in
occupational health since 1974. in 1980, he became the Medical Director of the Swedish Farmworker
Safety and Preventive Health Association - a very important model I think many of us could learn a
great deal from. He is currently also the First Vice President of the international Association for
Agricultural Medicine and Rural Health and also the Secretary of the Scientific Commitiee on
Occupational Health-a part of the international Commission, Please welcome Dr. Sverker Hogiiind
from Stockholm:

Agriculture is a risky operation. Statistics
from many parts of the world show that
accidents and work-related diseases are
frequent among farmers and agricultural
workers.

Often, however, statistics are insufficient
because farming, in many countries, is
based on small enterprises run by the
farmer, his family, and few employees.
The ambition to report accidents and other
health injuries is probably limited.

In Sweden severe accidents causing fatali-
ties are, fortunately, rather few in agricul-
ture. However, compared with the total
worklife in Sweden, it is obvious that farm-
ing is over-represented among fatalities
due to work accidents.

It has been shown that about 20 percent of
the fatal accidents in Swedish worklife
occur w&hin agriculture ahd forestry. Only
about 3 percent of the total workforce are
occupied within this field. Recent studies
in our organization have shown that the
real incidence of work accidents is about
twice what is reported from official statis-
tics. Moreover, work-related diseases have

been shown to be cotion among farmers
and agricultural workers.

Forestry work by self-employed farmers is
the most ris@ operation in the total
worklife in Sweden. Work injuries, as well
as work-related diseases, are to a high
extent related to agricultural work using
different kinds of machinery. Machine
cl;tf2e;herefore, iS an important factor to
    .
        .

THE PROBLEM

Machine design may be related to hazards
of two kinds. One is accidents causing
acute injuries. The other is chronic inju-
ries or illnesses because of long-term,
unfavorable effects on the body during
work operations. Symptoms from the loco-
motor organs are most common because of
bad ergonomics, vibrations, etc. Hearing
loss due to damaging noise is also very
frequent.

Accidents

In Sweden, approximately 150,000 persons
are occupied within agriculture and forest-

Surgeon General's Conference on Agricultural Safety and Health - 1991               351


intervention - Worker Protection from Environmental Hazards

x-y. However, only about 50,000 are occu-
pied full-time at this.

According to official statistics, about 6,000
work accidents occur yearly. This informa-
tion is based on the reports of injuries for
workers' compensation. The compensation
is less well developed for the self-em-
ployed farmer. Therefore, the ambition to
report accidents is less strong.

During 1988, the Swedish Farmers' Safety
and Preventive Health Association studied
20,000 farmers concerning work injuries
that had occurred during 1987. The study
was performed as a postal inquiry and a
telephone interview with those who had
reported an injury in the inquiry.

Machine design may be related to
hazards of two kinds. One is accidents
causing acute injuries. The other is
chronic injuries or illnesses because of
long-term, unfavorable effects on the
body during work operations.

From the results of this random sample, an
estimation of the total frequency of work
accidents within agriculture and forestry
among self-employed farmers and forestry
owners could be made. It showed that the
real frequency during 1987 was at least
double that of the official statistics.

The most common cause of agricultural
accidents (just above 25 percent) was han-
dling animals. Falling, on the same level
or to a lower level, was almost as common
a reason for accidents. Machine-related
accidents were about 12 percent in
agriculture, and in forestry about 20 per-
cent.

352

Of those accidents related to tractor driv-
ing, about 50 percent happened when
climbing up and down the tractor ano
about 35 percent when connecting equip-
ment to and disconnecting it from the
tractor. In these respects, the design of
the machinery plays an important role.

The turnover of tractors is still an impor-
tant reason for severe accidents, as is un-
shielded power takeoff (PTO). Tractor
work may also cause injuries driving on
uneven surfaces. Headbumps and hits
from the inside of the tractor cabin are a
risk, as are hydraulic devices with oil under
pressure. Sometimes exhaust gasses may
cause problems.

One important machine that is commonly
used in agriculture and forestry is the
chainsaw. It may cause accidents by kick-
backs of the sword.

Chronic Injuries and Diseases

More than 50 percent of the diagnoses at
physicians' consultations with farmers con-
cern locomotor organs. Neck and shoulder
symptoms, back problems, and hip and
knee diseases are common.

A special interest has been focused on hip
arthrosis. Recent studies in our country
have shown a significant increase of this
disease in farmers compared to the general
population. The disease occurs about 8 to
10 times more often in farmers. Still, only
limited studies have been performed relat-
ing different factors in farmwork to the
disease.

So far results indicate that there is a posi-
tive correlation between tractor work and
the disease. One reason might be the de-
sign of tractors where, even in modern
machines, the driver has to sit in a bent

Papers and Proceedings


Machine Design, May 1, 1991

and twisted position to survey the equip-
ment behind the tractor.

It has been suggested that the twisted
position in the tractor chair may cause a
rotation in the hip joint. It can also cause
unfavorable pressure on the cartilage,
which may cause damage.

Other well-known machine-related chronic
injuries are, for instance, white fingers
caused by vibration in chainsaws and steer-
ing wheels on tractors. In farmers and
forestry workers, hearing loss is frequent
because of noise exposure from tractors
and other vehicles, threshing mills, and
chainsaws.

INTERVENTION

There is still a lack of knowledge concem-
ing hazardous effects of different environ-
mental factors in agriculture and forestry
and further research is needed about caus-
al relationships. However, today sufficient
knowledge exists to start to improve the
work environment in order to reduce the
health hazards. The outline for an inter-
vention program could consist of three
main parts.

1. There may be legal actions taken in
order to prevent extreme hazards.

2. There should be strong enforcement on
constructors, manufacturers, and dealers
of agricultural machines in order to
improve the working environment.

3. Information and education must be in-
tensified and directed to dealers of ma-
chinery, extension service officers
(agents), farmers, farm workers, and
forestry workers.

Legal Considerations

In most countries there is some legislation
concerning work environment and protec-
tion from health hazards. The extent to
which legislation should be used is always
under debate. The ambition is to have as
little legal enforcement as possible.

In Sweden in 1959 the law was put forward
concerning safety frames (roll-over protec-
tion structures) in new tractors. It was also
decided that employed agricultural workers
were not allowed to work in tractors lack-
ing such frames. Self-employed farmers
and family members for many years were
excluded from this law and could use old
tractors without frames in farm work. A
new tractor, of course, had this device.

In 1983 the law was extended to include
family farmers. It was later decided that
even old tractors had to have frames if
they were to be used in agricultural work.

The effect on fatalities due to tractor turn-
over since the year of legislation was strik-
ing. It is obvious that this action from the
authorities, unpopular as it might have
been, has had quite a significant effect in
preventing severe accidents. Side effects
of this safety frame law have resulted in
proper cabins on the tractors protecting
the worker from noise, dust, wet, cold, etc.
This is also quite a step forward concern-
ing work environment.

Another example of effective legislation
concerns chainsaws. When they came into
frequent use, it was soon obvious that they
could cause severe damage to the user by
so-called kickbacks. In 1971 in Sweden, it
was enforced by law that a special protec-
tive device should be applied to all saws.

Surgeon General's Conference on Agricultural Safety and Health - 1991

353


intervention - Worker Protection from Environmental Hazards

It operates so that when the sword is flung
backwards, the device causes the chain to
stop. The drop in severe injuries from
chainsaw operations is also significant from
the time the law was introduced.

Improvement of Machine Design

Legal actions can only be taken into con-
sideration concerning specific work envi-
ronment factors causing severe injuries of
high frequency. However, many hazards
remain where improved design of the ma-
chinery could reduce the risk. It is impor-
tant that occupational health professionals
have the possibility to transmit knowledge
about health effects of different factors to
the designers of machinery, the producers,
and dealers. In industry more work has
been done in this area, mainly due to ef-
forts from workers, and representatives in
trade unions, etc.

In agriculture and forestry, labor unions
are weaker and the workforce is
dominated by self-employed farmers. The
individual farmer has very little possibility
to get his opinion known to the machine
designers.

One major task for occupational health
organizations in agriculture is, therefore, to
improve communication between manufac-
turers and users. When designing new
equipment, they must understand the im-
portance of also considering work environ-
ment factors.

In Sweden, we have been able to produce
a specification of the demands for good
and healthy work environments in tractors.
It has resulted in a checklist. The work
has been performed in close collaboration
with the National Institute for Occupation-
al Health, the organization of the machine
manufacturers (LELA), and our organiza-

354

tion. The checklist now also exists in an
English version.

It is our hope that it should be accepted
and used on a broad international basis.
We have planned to invite representatives
of tractor manufacturing companies to a
seminar concerning this topic a year from
now.

There is, of course, standardization work
going on internationally considering work
environment factors. However, this check-
list goes much further and aims to create a
work environment that is healthier in all
aspects.

We have recently used the checklist per-
forming a test of new tractors from the
ergonomic and work environment point of
view. The result has been published in the
weekly farm magazine called Land. It has
been very much appreciated by the farm-
ers.

The manufacturers who got many stars for
their tractors are, of course, happy. Those
with fewer stars have been rather angry
with us. We think, however, that it is our
job to take this kind of action.

Our experience is that, after the first disap-
pointment and angry reactions, the dealers
with less than good results usually come
back and ask for our opinion on how they
could make their equipment better. This
is exactly what we have wanted with our
action.

Today it often occurs that a manufacturer
of some equipment asks for our opinion
when he is planning a new product. When
this happens, we think that our work has
been, to some extent, fruitful.

Papers and Proceedings


To prevent injuries, there is still much to
wish for in tractor design. The power-
take-off shield is often of bad design and
broken in many older tractors, which caus-
es a significant risk.

In collaboration with the Institute of Agri-
cultural Engineering, we have been en-
gaged in the construction of a new device.
This seems to be a significant step forward.

The coupling of equipment behind the
tractor often causes injuries. The rapid
coupling systems, which exist on the mar-
ket are not ideal and little used by the
farmers. Properly used, they cause a sig-
nificant reduction of work loads and health
hazards.

A big part of the injuries related to tractor
work occur when the driver is climbing up
and down the steps. They are often of a
miserable design and get slippery by dirt.
Simple devices can improve this.

The chronic diseases concerned with trac-
tor driving are neck, shoulder, back, and
hip problems related to the driver's twisted
and bent position while controlling the
equipment behind the tractor during long
working hours. Knee problems are com-
mon in tractor driving and are related to
too-heavy clutches. As much as 600-700
newtons have been found in new tractors.

In the new ergonomic check list, 150 newt-
ons has been appointed as acceptable.
Valmet, the only Nordic tractor construc-
tor, presented a new model a couple of
years ago where many of these problems
have been considered.

The driver's seat, steering wheel, and ma-
neuvering devices could be turned 180
degrees so that the driver might sit in a
backward position when much work had to

Machine Design, May 1, 1991

be done with equipment behind the trac-
tor. There was no clutch because of hy-
drostatic driving of the machinery.

Two important improvements from the
work environment point of view were
achieved by this construction. The need to
sit in a twisted position was markedly re-
duced, and the clutch operation was no
longer needed. We need more of this new
and brave thinking in the machine design
for the future. Because of other technical
reasons, the model still is experimental.

It still happens that kickbacks cause in-
juries concerning chainsaws. A Swedish
doctor has constructed a new protection
device, which should be more effective. It
is now tested. The Swedish firm,
Husquama, is going to provide some
models with this new and safer device.

Increased Awareness

In spite of legal considerations and
improved machine designs, there will still
be hazards concerned with machine
operations. It is, therefore, important,
along with other actions, that knowledge
about health hazards and how they can be
prevented is increased. This is needed
among the users of agricultural machinery
and also among advisers within different
branches of extension services to farmers,
and among dealers of agricultural machin-
ery.

It is a difficult task. Farmers are usually
very busy and get much information of dif-
ferent kinds. They have very little time to
consider different offerings. Written infor-
mation often is neglected. The motivation
to consider information about health haz-
ards is usually low among people who are
quite healthy and do not consider
accidents a reality.

Surgeon General's Conference on Agricultural Safety and Health - 1991               355


Intervention - Worker Protection from Environmental Hazards

One way to improve the possibility to get
information through is by an occupational
health service. In Sweden since 1978,
occupational health service for farmers and
farm workers has been organized and now
covers the whole country.

It has about 60,000 affiliated members.
Our customers are offered services consis-
ting of regular health checkups, infor-
mation meetings, farm visits, short courses
concerning specific health problems, first
aid, back and neck schools, etc.

They also have access to health care in
case of medical problems related to work.
It has turned out that the awareness of
health hazards has increased considerably
during the last years.

The farmers inquire about work-environ-
ment factors when they are buying new
machinery more than previously. They are
also inclined to use the personal protective
equipment more frequently. Nurses per-
forming health checks on farmers, physio-
therapists, and safety engineers visiting
farms pointing out ergonomic details to the
farmer on his tractor have golden opportu-
nities to provide information to motivated
farmers.

It is also possible to concentrate on one
specific problem and to broaden the infor-
mation by educating advisers to the
farmers. An ongoing project is to produce

information materials concerning the new
ergonomic checklist and to give the ex-
tension service officers and safety engi-
neers education on how to use it in their
work with the farmers. Teachers at agri-
cultural schools and dealers of agricultural
machinery are also invited to these cour-
ses.

CONCLUSION

Today's knowledge about health hazards in
relation to machine operations is fragmen-
tary but, in many cases, enough to start
prevention programs. Thus, the hazards
may be reduced and health and well-being
improved among farmers, farm workers,
and forestry workers.

Legal actions may considerably reduce
specific risks associated with machine de-
sign. By influencing constructors and man-
ufacturers, improved work conditions can
be achieved.

By effective information and education
awareness of hazards, preventive measures
can be augmented. A branch-specific oc-
cupational health service for agriculture
and forestry is a valuable tool in this re-
spect.0

356

Papers and Proceedings


Surgeon General's Conkrence on Agricuttural Safety and Health
FARM&WE 2000 o A National Coalition rbr Local Action
Convened by the National lnstituie riv Occupational Safety and Health
April 30 - May 3, 1991, Des Moines, Iowa

VECTOR CONTROL

       By Robert R Pinger, Ph.D.
      Public Health Entomology Laboratory
Department of Physiology and Health Science, Ball State University

Farmers, ranchers, and others employed in
agriculture are, by the very nature of their
work, at significant risk for acquiring cer-
tain vector-borne diseases. Some of you
may ask, "What is a vector-borne disease?"
or, for that matter, "What is a vector?"

A vector is an invertebrate animal, usually
an arthropod, that transmits disease from a
reservoir of infection to a susceptible host.

What is an arthropod? An arthropod is a
joint-footed animal with a hardened exos-
keleton such as an insect or a tick. Exam-
ples of arthropod vectors are mosquitoes,
flies, fleas, lice, and ticks.

Vector-borne diseases are caused by mi-
croscopic agents such as viruses, bacteria,
protozoans, or worms transmitted by these
vectors, usually when they bite. Examples
of vector-borne diseases that occur here in
the United States include at least four
arthropod-borne encephalitides, malaria,
dengue fever, Rocky Mountain spotted
fever, and Lyme disease.

Before I discuss these diseases, I should
like to state that those in agriculture are

Dr. David S. Pratt: We are going to move along to this morning's program with Dr. Robert Pinger.
Dr. Pinger got his undergraduate training at San Jose State in California, and received a master's and
a Ph.D. from Iowa State University, right here in the great state of Iowa. He has worked extensively
with vector control and entomological research both at the National Research Council at Waiter Reed
Army Institute of Research in `74 and `75, and then also had some tropical experience in Brazil as an
associate research scientist at the National Research institute of the Amazon. Since 1977, a little less
tropical, he has been at Ball State University in Muncie, Indiana, and his current research interests
include mosquito- and tick-borne diseases. Dr. Pinger's going to talk about vectors and agricultural
safety and health. Dr. Pinger:

also exposed to a variety of arthropod-
related health problems. The insects or
arthropods are themselves the agents of
disease or injury.

In these cases, the arthropods affect health
directly, rather than indirectly (as vectors).
Direct effects include entomophobia (an
unrealistic fear of insects), annoyance and
blood loss, envenomization caused by bit-
ing and stinging, dermatosis, myiasis, and
allergies.

ENVENOMIZATION

My students are sometimes confused about
the difference between biting and stinging.

Biting

Biting refers to interactions in which the
arthropod uses its mouth parts. Biting
insects include, but are not limited to,
mosquitoes, horse flies, fleas, lice, and
bugs.

Biting arachnids include ticks, such as the
American dog tick, the lone star tick, the
deer tick, and chiggers. Venomous arach-

Surgeon General's Conference on Agricultural Safety and Health - 1991               357


Intervention - Worker Protection from Environmental Hazards

nids include the brown recluse and the
black widow spider.

Stinging

Stinging refers to interactions in which the
arthropod uses its tail (usually a modified
ovipositor) to inject venom. Stinging ar-
thropods include bees, such as the recently
arrived Africanized honey bee; wasps,
including the newly introduced German
yellow jacket; and in the South, fire ants
and scorpions. Male entomologists, who
are easily in the majority, generally enjoy
pointing out at a time like this that virtual-
ly all of this biting and stinging is done by
female arthropods.

Although all too familiar, and at times very
annoying, these occurrences are of relative-
ly minor public health importance com-
pared with the disease transmission capa-
bilities of arthropod vectors. Today I will
describe some of these vector-borne dis-
eases, discuss vector control strategies and
outline personal precautions that can re-
duce the likelihood of vector-borne disease
transmission in the agricultural setting.

VECTORS

We can divide vectors into two major
types: mechanical vectors and biological
vectors.

Mechanical Vectors

As mechanical vectors, insects can be
thought of as contaminators. They carry
disease-producing agents from an
unwholesome environment, such as septic
tank overflow, to a clean environment such
as the top of your beverage can or sand-
wich.

358

In some rural settings, house flies may
become so numerous that they represent a
significant health problem. The variety of
disease-producing agents that have been
recovered from house flies is staggering.
The list includes those agents that cause
amebic dysentery, typhoid fever, cholera,
shigellosis, trachoma, poliomyelitis, and
infectious hepatitis.'

Another mechanical vector is the cock-
roach, from which about 40 strains of path-
ogenic micro-organisms have been isolated.
These microorganisms include four strains
of poliomyelitis virus, cholera, diphtheria,
pneumonia, tuberculosis bacteria, and
numerous intestinal protozoans. Mechani-
cal transmission can also occur when a
blood-feeding insect, such as a horse fly or
stable fly, is interrupted while feeding
upon an infected host, then completes its
feeding on a susceptible host.

Although mechanical transmission by flies
and cockroaches can be of public health
concern in some agricultural settings, bio-
logical transmission of diseases by arthro-
pods is much more important. In biologi-
cal transmission, the disease microorgan-
ism undergoes developmental changes
and/or multiplication in the vector.

There is also an incubation period during
which the arthropod is infected but not
infectious. It is unable to transmit the dis-
ease. After incubation, the arthropod be-
comes infectious, and remains so for life.

Biological Vectors

Examples of biological vectors include
mosquitoes, ticks, fleas, lice, and certain
other biting flies. Mosquitoes, the most
notorious of all insect vectors, are capable
of transmitting at least 3 species of filarial
worms, 4 species of malaria, and a large

Papers and Proceedings


number of disease-producing viruses. Of
the roughly 500 different arthropod-borne
viruses catalogued, 249 have been isolated
from mosquitoes.2

Ticks also transmit a variety of disease
agents including those that cause
babesiosis, Lyme disease, Rocky Mountain
spotted fever, Colorado tick fever, and
Powassan fever. Disease agents transmit-
ted by other insects include murine typhus
and plague, transmitted by fleas; epidemic
typhus and trench fever, transmitted by
lice; and a multitude of viruses, bacteria,
protozoans and worms transmitted by bit-
ing flies and gnats.

On a worldwide basis, vector-borne diseas-
es continue to affect the health of agricul-
tural workers on every continent. In Afri-
ca the tsetse fly and sleeping sickness not
only cause 7,000 human deaths per year,
but also limit cattle production over 10
million km'. Therefore, they contribute to
the severe protein malnutrition on that
continent.

Malaria and mosquito-borne encephalitis
affect rice farming in Sri Lanka and el-
sewhere in Asia.3 Yellow fever afflicts
those clearing forests for farming in parts
of Central and South America.

In the United States, most of the vector-
borne diseases that have an impact on
agriculture and agricultural health are
zoonoses, diseases of animals transmissible
to humans. Among the best known zoono-
ses are those caused by four mosquito-
borne viruses: the St. Louis encephalitis
(SLE), the California encephalitis (CE)
viruses, the western (WEE) and eastern
equine encephalomyelitis (EEE) viruses.
Each of these diseases has its own
geographical distribution and pattern of
transmission.

Vector Control, May 1, 1991

While periodic outbreaks of these mosqui-
to-borne viral encephalitides occurred, no
doubt, long before the arrival of Europe-
ans", accurate records of outbreaks date
only to the 1930's. Between 1930-1945,
mosquito-borne encephalitis killed an
estimated 300,000 horses and mules in the
U.S.5 Human illnesses were often associat-
ed with these epizootics.

For example, in 1941 North Dakota alone
reported 1,080 human cases with 96
deaths.6 During the period 1956-1969,
reported human cases of arthropod-borne
encephalitis numbered more than 3,000.

In 1975, both SLE and WEE were epidem-
ic and epizootic throughout much of the
United States. There were more than
2000 human cases,' many of them in farm
workers. The WEE epizoodemic spread
into Manitoba, where the importance of
outdoor exposure is illustrated by the dis-
tribution of 14 human cases.

All but three of these cases were men.
Interestingly, all three women who con-
tracted the disease were widows who pre-
sumably then did more outside chores than
their married counterparts.

Why do we not hear about these diseases
anymore? Are they still around?

Let me call your attention to last year's St.
Louis encephalitis outbreak in Florida.
Although case investigations are still being
completed, the first case occurred in Fells-
mere, Florida, an agricultural area. At
least some of the cases were in farm work-

ers.

The economic impact of this outbreak is
still being felt. Disneyworld receipts were
off lo-25 percent for October through
December. The annual costs of mosquito

Surgeon General's Conference on Agricultural Safety and Health - 1991                359


Intervention - Worker Protection from Environmental Hazards

control ran $2-4 million above the normal
cost, and there was a $270 million short-
fall in Florida's tax revenue for 1990.8

It is true that the current epidemics and
epizootics seem less pronounced than
those of 50-60 years ago. There are sever-
al reasons for this. First, there are fewer
horses now than there were in the 1930's
and 1940's.

Second, vaccination of many of the
remaining horses against WEE and EEE
has no doubt contributed to the elimina-
tion of large epizootics in horses. This
does not explain the decline in human
cases, however, particularly when there is
no evidence of a decrease in the level of
virus activity in nature.

Gahlinger, Reeves, and Milby postulate
that changes in people's behavioral pat-
terns have been responsible for the decline
in human cases in California. Their study
demonstrated that the advent of air condi-
tioning and television substantially reduced
exposure to infectious mosquitoes. People
were found to prefer remaining indoors
during the peak feeding times of the pri-
mary vector, Culex tarsalis.g

Others suggest that the low number of
confirmed cases is a product of our dis-
ease-reporting system. This phenomenon
has been referred to as the "vector-borne
disease iceberg."

In this model, we see that most of the
cases of mosquito-borne encephalitis are
never reported because of misdiagnoses,
poor follow-up, and no confirmatory serum
sample. Grimstad and coworkers deter-
mined that the ratio of reported cases to
actual cases in Indiana is about 1:250 for
St. Louis encephalitis. The ratio of report-

ed cases was l:l,OOO for the Lacrosse
strain of California encephalitis."

Some cases are reported incorrectly as
aseptic meningitis or "unspecified viral
encephalitis." Cases often end up in this
category when no convalescent or follow-
up blood sample is submitted. The season-
al distribution suggests, though, that they
are, in fact, arthropod-borne illnesses.

A failure in reporting is less likely to occur
when there is a severe or fatal case. It is
important to note that, in addition to the
pain and suffering associated with a severe
case, there can be significant medical costs.
This is particularly true if the patient is a
child who requires many years of institu-
tional care.

Leaving the encephalitides, I want to men-
tion two other mosquito-borne diseases
that affect those in U.S. agriculture: ma-
laria and dengue fever. Malaria, transmit-
ted by Anopheles mosquitoes, is once again
becoming a concern in California where
there have been 60 introduced cases in the
last 5 years, virtually all in farm workers in
San Diego County."

Florida suffered its first introduced case in
43 years in 1990. An introduced case
differs from an imported case in that it is
one in which transmission occurs within
the state.'

Another somewhat vector-borne disease
that we have thought of in the past as an
exotic disease, but which now poses a very
real threat to many in agriculture is den-
gue fever. Health officials are concerned
that the dengue fever virus, imported from
the Caribbean into California or Florida
with the migrant workforce, could also be
transmitted within the United States.

360

Papers and Proceedings


This becomes increasingly more likely with
the spread of the Asian tiger mosquito,
Aedes albopictzq which is now considered
to enjoy a statewide distribution in
Florida.' This specie, which arrived in the
United States from Asia in imported truck
tires in 1984 or 1985, is a more aggressive
biter and a more efficient vector of the
dengue fever virus than the yellow fever
mosquito, Aedes aegypti.12 l3

Since the early 1980's, tick-borne diseases
have received much more publicity than
mosquito-borne diseases. Who has not
heard of Lyme disease?

For those who have not, Lyme disease is a
systemic, bacterial, tick-borne disease with
protean manifestations including dermato-
logical, arthritic, neurologic, and cardiac
abnormalities. It is caused by the spiro-
chete, Borrelia burgdorferi, which is trans-
mitted by ticks in the Ixodes ricinw group.
It is often the nymphal stage of these ticks
that transmits the disease. The most
noticeable early sign is a red rash emanat-
ing from the site of the bite.

The disease has spread rapidly in the
United States since its discovery in 1975.
It has now been reported from 47 states
including, most recently, New Mexico.14

Actually during the period 1983-1987, tick-
borne diseases made up more than three-
quarters of all reported cases of vector-
borne disease in the United States."
Rocky Mountain spotted fever actually
declined during the 1980's from a high of
0.52 cases per 100,000 in 1980, to 0.25
cases per 100,000 people in 1989.`""

Meanwhile, Lyme disease showed a dra-
matic increase over the same period from
0.10 cases per 100,000 in 1980, to more
than 3.5 per 100,000 in 1989. The 1990

Vector Control, May 1, 1991

case data are still incomplete for some
states. It appears, however, that the num-
ber of reported cases of Lyme disease may
be leveling off or even declining slightly.
This may be due to a change in the case
definition, which now requires laboratory
confirmation of clinical cases without a
rash.

VECTOR CONTROL

The title given to this presentation was
Vector Control. Obviously, in the time
remaining, I cannot tell you how to control
all of the species of mosquitoes, ticks, flies,
and other vectors that are of importance to
the occupational health of American farm-
ers.

I can review some widely accepted guide-
lines, however. There are three approach-
es to vector control: physical control,
chemical control, and biological control.

Physical Control

Physical control is the modification of the
environment to reduce or eliminate vector
populations. This type of vector control is
the most desirable because it is the most
permanent. Populations of mechanical
vectors such as house flies and stable flies
can be reduced or eliminated by maintain-
ing proper sanitary conditions.

For example, the regular removal of live-
stock and pet manure, soiled bedding,
straw, garbage, and all other decaying
plant and animal matter will reduce breed-
ing sites for house and stable flies. Sirni-
larly, cockroach problems can be reduced
or eliminated by the proper construction of
human dwellings, regular cleaning, proper
food storage, and food waste disposal.

Surgeon General's Conference on Agricultural Safety and Health - 1991

361


Intervention - Worker Protection from Environmental Hazards

The distribution of the mosquito-borne dis-
eases correlates closely with the
distributions of their primary mosquito
vectors. Since all mosquitoes are depen-
dent upon standing (or very slow moving)
water during the early stages of their de-
velopment, proper water management in
agriculture can substantially reduce the
risk of infection with these diseases.

In the west, physical control means effi-
cient water management with respect to
irrigation and other methods of watering
crops. In the east and midwest, those in
agricultural settings should strive to elimi-
nate all standing water near the home.

This means ditching, draining, or filling
low areas near homes whether under cul-
tivation or not. It means maintaining
steep, weed-free banks in man-made ponds
and lakes. It means removing all man-
made and natural water holding containers
from near the home.

Integrated Pest (Vector) Management
(IPM) is the use of the safest and most
appropriate combination of methods
(physical, chemical, and biological) to
control vector populations.

These containers afford breeding sites for
the vectors of Lacrosse encephalitis.
Examples of containers that should be
eliminated are rain barrels; used car, truck
or tractor tires; paint buckets; and plastic
containers of all kinds. Tree holes that are
found should be filled in with sand or
cement.

Physical control methods for ticks include
the removal of ail unnecessary shrubs and
vegetation from near living quarters, the

362

extension of the mowed portion of the
yard, and the regular and close mowing of
grass for at least a 50 foot perimeter
around the house. The greatest enemy of
ticks is desiccation. By removing vegeta-
tion you reduce the survival time of ticks.

Chemical Control

Chemical control is the use of chemical
agents (pesticides) to reduce or eliminate
vector populations. Chemical control is
best viewed as an adjunct to physical con-
trol.

When properly applied, it can be of great
assistance in lowering the risk for disease
transmission on a temporary basis. There
are many excellent chemicals on the mar-
ket for mosquito and tick control.

However, we are all familiar with the
problems associated with extensive reliance
on chemical control. These include the
development of resistance, the destruction
of non-target organisms, and cost.

Biological Control

Biological Control is the use of biological
agents, such as microorganisms, other ar-
thropods, or vertebrates, to reduce or elim-
inate vector populations. In' sqme respects,
biological control is a promise that has
never been fulfilled. Nonetheless, the use
of mosquito fish, Gambusia, and the spore-
forming bacteria, Bacillus thuriqqiensis var.
`israelensis, have been moderately success-
ful in mosquito control.

Integrated Pest Management

Integrated Pest (Vector) Management
(IPM) is the use of the safest and most ap-
propriate combination of methods (physi-
cal, chemical, and biological) to control

Papers and Proceedings


Vector Control, May 1, 1991

vector populations. In medical en-
tomology, IPM means the reduction of a
vector population to a level below that
which poses a significant health risk.

PERSONAL PROTECTION

Personal protection offers another avenue
for lowering your risk of acquiring a vec-
tor-borne illness. Personal protection is
the practice of health-directed behavior
that reduces the risk of acquiring a vector-
borne disease infection. Examples include
the following:

1. Avoiding areas where and when vectors
are present.

2. If you must enter these areas, wearing
the proper clothing (long pants and long
sleeved shirt, socks, and shoes).

REFERENCES

Use repellents properly and ap-
propriately.

Removing ticks promptly using the
correct method. Prompt removal great-
ly reduces risk of disease transmission.
Grasp the tick as closely to the skin as
possible and pull slowly and directly
out.

Notifying a physician if illness occurs.
Be sure to mention a tick if you are
suspicious.

knowledge of vector-borne diseases, a

sound understanding of approaches to vec-
tor control, and a familiarity with
procedures for personal protection can
reduce the risk of contracting a vector-
borne disease.0

1.

2.

3.

4.

5.

6.

7.

8.

Harwood, Robert F. and M.T. James. Entomology in human and animal health. 7th Ed., New York:
MacMillan Publishing Co., 1979.

Karabatsos, N. (Editor). International Catalogue of Arbovimses Including Certain Other Kruses of
Vertebrates. 3rd Edition, San Antonio, TX, American Society of Tropical Medicines and Hygiene, 1985.

Lacey, LA. and C.M. Lacey. "The Medical Importance of Riceland Mosquitoes and Their Control Using
Alternatives to Chemical Insecticides," Journal of the American Mosquito Control Association. June 1990.
(Supplement No. 2.) pp. l-93.

Chamberlain, R.W. "Historical Perspectives on the Epidemiology and Ecology of Mosquito-Borne Viral
Encephalitides in the United States," American Journal of Tropical Medicine and Hygiene. 37(3). (Supple-
ment): pp. 8-17, 1987.

Steelman, C.D. "Effects of External and Internal Arthropod Parasites on Domestic Livestock Produc-
tion," Annual Review of Entomology. Vol. 21, pp. 155-178, 1976.
Leake, J.P. "Epidemic Infectious Encephalitis," Public Health Reports. U.S. Public Health Service, 56(11)
39: pp. 1902-1905, 1941.

Centers for Disease Control. Encephalitis Surveillance Report Annual Summary 1975. Issued May 1977. l-
23.

John A. Mulrennan, Entomologist, State of Florida, HRS, P.O. Box 210, Jacksonville, FL 32231, Personal
Communication, April 25, 1991.

Surgeon General's Conference on Agricultural Safety and Health - 1991               363


Intervention - Worker Protection from Environmental Hazards

9. Gahhnger, P.M., W.C. Reeves and M.M. MiIby. "Air Conditioning and Television as Protective Factors
in Arboviral Encephalitis Risk." American Journal of Topical Medicine Hygiene. 35(3) pp. 601610.

10. P.R. Grimstad, C.L. Barrett, R.L. Humphrey, and MJ. Sinsko. "Serological Evidence for Widespread
Infection with Lacrosse and St. Louis Encephalitis Viruses in the Indiana Human Population." American
Journal of Epidemiology, 1 19; pp. 913-930, 1984.

11. Bruce F. Eldridge, Department of Entomology, University of California, Davis, Personal Communication,
April 19,1991.

12. Hawley, WA. 1988. "The Biology of Aedes albopictus, " Journal American Mosquito Control Association.
December, 1988, Suppl. No. 1. pp. l-40.

13. Francy, D.B., C.G. Moore, and DA. Eliason. "Past, Present and Future of Aedes albopictus in the
United States," Journal American Mosquito Control Association. 6(l); pp. l27-l.32, 1990.

14. Centers for Disease Control, Division of Vector-borne Infectious Disease. "Update on Reported Cases of
Lyme Disease 1989," Lyme Disease Surveillance Summay. l(2), p. 1, 1990.

15. Centers for Disease Control. "Lyme Disease-United States, 1987 and 1988," Morbidity and MortaZity
Week& Report. 38(39), pp. 668-672, 1989.

16. Centers for Disease Control. "Rocky Mountain Spotted Fever and Human Ehriichiosis-United States,
1989,"Morbidity and Mortal@ Week& Report. 39(17), pp. 281-284, 1990.

17. Centers for Disease Control. "Summary of Notifiable Diseases, United States, 1989, "Morbidity and
Mortality Weekly Report, pp. 38(54). 1989.

364

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Suqeon General's Conference on Agrkuhuml Satkty and Health
FARMSAFE 2000 o A National Coalition for Local Action
Convened by the National Institute for Occupational Safety and Health
April 30 - May 3, 1991, Des Moines, Iowa

A CONSULTING ENGINEER'S PERSPECTIVE

     By Ray H. Crammonrt, P.E.
Consultlng Engineer, Crammond Engineering Company

Dr. David S. Pratt: The first perspective we will have is from a consulting engineer. Ray Crammond
is a consulting engineer born here in Iowa and a graduate of Iowa State University. He has an
extensive career and background both with county government and also as a private engineering
consultant, at least since 1978. He has extensive knowledge dealing with farm-related and rural
resident Issues. We are very happy to have A Consulting Engineer's Perspective.
Mr. Ray Crammond:

First of all I would like to say I appreciate
the opportunity to be here to speak to you  I have been asked why I got involved in
today, and this is an issue I have a lot of   consulting work. The best way to put it is
                   I figured it was easier than farming. I

interest in. I am glad that the session
carried over to this afternoon, because I
was tied up this morning in a deposition.
It did not have to do with personal injury,
just manure run-off between two neigh-
bors.

grew up on a farm in Southeast Iowa, and
I am still involved in the farm, but I always
figured there had to be a better way of
doing things. So that is how I got into the
agricultural engineering.

A lot of times misunderstandings come up  We talked some about stress the past day
                    or two. In the 1950's, wheat was $3 a
when you try to talk about a subject. As   bushel and psychiatry was $3 an hour.
an example, I was reminded of an agricul-
tural engineer who had phoned a veteri-   In the 1960's wheat was only $3 a bushel,
narian, and he said, "Say, DOC, I have got a  psychiatry was a little bit better operation;
sick cat. He just lays around and licks his   it was $20 an hour.
paws. He has no appetite. What should I
do?" The guy replied, "Give him a pint of  In the 70's, wheat was still $3 a bushel.
castor oil." Somewhat dubious, the agricul-  Psychiatry was a little bit fancier digs, and
tural engineer forced the cat to take the    it was $60 an hour.
pint of castor oil and a couple of days later
he met the vet in town, and the fellow    In the 1980's the farmer was into the psy-
said, "Well, how's your sick calf." He says,  chiatrist at $100 an hour, and the wheat
"Sick calf? That was not a sick calf; it was  was still $3 a bushel. That is the way
a cat." He said, "Well, you did not give
him the castor oil, did you." "Sure did,"   things have gone, and that is one of the
                         reasons for the stress that the farm com-
said the agricultural engineer, "last time I  munity is facing.
saw him he was going over the hill with
five other cats. Two were digging, two    On the other hand, some people have the
were covering up, and one was scouting for  idea that an engineer has a life where he
new territory."              can just sit back and say, "Yes, I went
                  through your plans a few minutes ago, and
                         that's all there is to it."

Surgeon General's Conference on Agricultural Safety and Health - 1991               365


Intervention - Worker Protection from Environmental Hazards

ENGINEERING

This was a quote from Herbert Hoover
who was an engineer as well as a number
of other jobs that he had. He talks about
it being a great profession:

. ..the fmcination of watching the pigment
of the imagination merge through the aid
of science, to a plan on paper, that moves
to realization in stone, or metal, or energy;
and it brings jobs and homes to man; and
then it elevates the standards of living and
adds to the comforts of lve.  That is the
engineer's high privilege.

The great liability, of the engineer, com-
pared to men of other professions, is that
his works are out in the open where all
can see them. His acts, step-by-step are in
hard substance. He cannot bury his rnis-
takes as a-you can kind of fill in the blank
with other professions.

He cannot argue them into thin air or
blame someone else. He cannot cover his
failures with trees and vines, and he can-
not screen his shortcomings by blaming his
opponents and hope the people will forget.
In other words, if he screws up, he is
responsible.

On the other hand, his is not life among
the weak; destruction is not his purpose;
quarrels are not his daily bread. That is
one of the reasons why a lot of engineers
do not like to get involved in liability cases
or product suits.

To the engineer falls the job of clothing
the bare bones of science with life, com-
fort, and hope. No doubt, as the years go
by, people forget which engineer did it,
even if they ever knew, or some politician
puts his name on it, or they credit it to

366

someone else who used other people's
money.

But the engineer himself looks back at the
unending stream of goodness that flows
from his successes with a satisfaction that
very few professions may know. The ver-
dict of his fellow professionals is all the
accolade he wants.

I think that holds true in a lot of cases for
the people in the engineering profession.
The problem is that in some cases,
depending on a person's temperament,
training, background, or whatever, the
engineering procedure can start you out
with a simple premise that the sum of two
quantities in the form of one plus one
equals two; but then as you study and get
deeper into your subject matter you know
that one equals log of e and that one
equals sine' x plus cosine2 x and so forth.

You get down there and rewrite all those
equations. At this point it should be obvi-
ous that equation three is much clearer
and more easily understood than equation
one. Other methods could be used to
clarify equation one, but these are easily
discovered once the reader grasps the
underlying principals.

I think too many times what happens when
you talk about whether it is the design of a
product or a tax code, whatever it might
be, you know that one plus one equals two,
but to get back to it, after going through
what is on the bottom line there, you won-
der where you are at.

This is one of the definitions I like about
engineering; It is the art of directing the
great sources of power and nature for the
use and convenience of man.

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Another thing regarding engineers is the
study of both human needs and natural
phenomenon. These two fields of study
give essential unity to the profession for all
engineers, whatever their specialty, must
know both human ways and natural forces.

Human Needs

One of the biggest problems I have seen in
the 20 years since I have gotten out of
college, in the work that I do, is that the
engineer-if I am looking at a particular
problem on a site or whatever-has looked
at only the natural forces. They ignored
the human forces - whether by their na-
ture, the course of study, or whatever, they
tend to drop one-half of the input there.
That is where a lot of problems occur.

So, I think the biggest problem is people
71
I had one engineer say, on a grain bin case
that, "Well, if there was a warning saying
that it should only be piled to a certain
level, by gosh that is what it should be.
The grain should be put in at that level."

Knowing how farmers operate and how
equipment operates, if you have a building
that is about 200 feet wide and over 600
feet long and you are running grain in
there at 17,000 bushels an hour, you prob-
ably will not hit that line right on the nose.
You had better figure that what can be put
in there up to the eaves is going to be put
in there up to the eaves. If you do not
design to that, you are only fooling your-
self.

A Consulting Engineer's Perspective, May 2, 1991

So, I think the biggest problem is people
who ignore the human input. It is where
they run into trouble.

Natural Phenomenon

It would be a lot easier these days to be,
another type of engineer than an agricul-
tural engineer because on top of every-
thing else that we have got to contend
with, just when we think we have got all of
our data down we have to deal with some
new factor. Whether it is growth hormone
that suddenly changes the dimension of the
stalls or the strength of the animals, or
whatever it might be.

You can also run into unexpected natural
phenomenon, after having, in the past 15
months or so, drilled 200 or 300 holes in
Iowa for waste storage basins for livestock
facilities. I have run into situations like
that.

SYSTEMS DESIGN

Now a couple of quick definitions from my
perspective. I get involved in product de-
sign, but more in systems design. If you
are talking about a contractor, well then
you are generally talking about a gambler
who never gets to shuffle, cut, or deal. A
bid opening is a poker game in which the
losing hand wins. There is the bid that is a
wild guess carried out to two decimal
points. The low bidder is the contractor
who is wondering what he left out. The
engineer's es&rate is the cost of construc-
tion in heaven. Meanwhile, the project
manager is the conductor of an orchestra
in which every musician is in a different
union.

Critical path methods, which some of you
may have used, is the management tech-
nique for losing your shirt under perfect

Surgeon General's Conference on Agricultural Safety and Health - 1991


Intervention - Worker Protection from Environmental Hazards

control. An auditor is a person that goes
in for the wounded after the war is lost
and bayonets the half maimed. A lawyer
is the person who goes in after the audi-
tors and strips the bodies.

"Free" Advice

I guess one of the things I have run into is
the value of free advice might be worth
less than what you paid for it. Too many
times I have seen situations where some-
body relied either on their good buddy or
friend, or whomever; maybe even on tech-
nical personnel, and come to find out that
they got into deep trouble when they relied
on a situation where they thought they
were getting a good deal.

Another case involved ventilation systems.
Well, the fellow himself was not so much
personally injured as he lost $50,000 worth
of hogs. You know, any fool can design a
ventilation system, a lot of people will say,
and so many do.

I have run into cases where you can lead a
client to enlightenment. We have been
talking about training and so forth. That is
all fine and good, but there are some cases
where they just simply will not pay atten-
tion to you, or go on about their business
and ignore you completely.

Disclaimers

Disclaimers should not be used to protect
poor design. How many times I have been
involved in grain bin cases-whether bin
drownings or bin collapses-somebody has
a decal or a warning saying, regarding roof
vents for instance, that they should be kept
cleaned out. The only way to get to them
is to tie yourself off on a rope and swing
out there like Tarzan to get to it, and

368

there are no ladders, nor access to it.
Does that make any sense?

Does it make the home office feel better
that you have got a disclaimer on there so
you are protected. To me it is just ridicu-
lous, and you are not fooling anybody,
especially the courts. You might find your-
self in a lawsuit.

Training

The other thing is it is easier to teach rules
and to train rules than to train judgment.
That is an area where we have to focus on
in training judgment, and we end up trying
to legislate common sense.

Poor Engineering

Poor engineering entails failure and mis-
fortune, inconvenience, suffering, death.

In one case three people died in a manure
pit when they went down to fix a pump
malfunction. In this situation could we
have pulled the pump out without having
to go down into a pit so a father and his
two sons would still be alive?

I remember on a project one time when I
was talking to a banker in 1974. He said,
"What do we need an engineer for? The
building company does all that?"

It turned out later - a few weeks later - I
got a call. He wanted me to work on this
particular project. Since that time, I have
had numerous referrals on similar projects.
But in this case they had a $300,000 build-
ing coming in a few weeks, and they had
made no provisions or planning on where
they were going to put this thing. So, they
finally came around to realizing that may-
be the building company does not do all of
that.

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Another comment that I hear out in the
field, "I got a special deal on this. How do
you like it." A lot of times not very well
because it usually leads to either failure or
injury; but, the guy got a good deal on it
so, to him, it was okay.

A farmer has a choice as to whether he
wants to buy this option or accessory item.
I think back to the time I sat through a
seven-hour deposition involving a bin
drowning. We started at nine in the mom-
ing and ended up at four. We did not
even break for lunch.

The poor court reporter's fingers were
about ready to drop off, I think. Some-
body brought in some candy bars at about
1:30 p.m. The question was given to me,
"Could this farmer buy these roof vents as
an accessory item?"

In this particular case I said, "In your own
manual it says that if the roof is installed
in a certain way with roof clips in the
down position where there's no gap, that
there must be one roof vent for every so
many cubic feet per minute of fan capaci-
ty." In this case, I think it figured out five
or six roof vents.

This 42-foot diameter bin had no roof
vents on it whatsoever. The fellow was in
there trying to poke down the corn with a
rod, trying to get it broken up so it would
feed into the unloading auger. They found
him in the middle of the bin about six feet
off the bottom.

It had just been minutes before that his
nine-year-old son was in there. If his wife
had not insisted that the son get out of the
bin, while she went to fix dinner that eve-
ning, he would have been in there, too.

A Consulting Engineer's Perspective, May 2, 1991

I pointed out to the attorney who asked
me that question, "In their own manual it
says that if the roof is installed in this
position, there must be a roof vent for so
many CFM of fan capacity. How can you,
in good conscience, tell me that this is an
accessory item?" He never asked me an-
other question.

That is where I think we get into the sys-
tems approach. In this particular case, the
farmer never got the manual, or he might
have discovered there was a problem that
he could have acted on differently. We
found in discovery that the manual was on
back order, and he never received it.

Why did you build at this site? "Well, the
salesman said it would work." That has
created a number of problems, in some
cases the health of people; in some cases
their pocket book. One case where people
spent over $300,000 were ready to move
some livestock into a building. They were
sued, and they had to change things.

"A bin is a bin," spoken by a farmer, a
social studies teacher, or someone who
bought a bin company because he wanted
to get into a business of his own. He put
up over 40-thousand bushel bins, and the
roof was blown out and disrupted the
farmer's income.

He was not around the bin at that time,
but he lost the bin, he lost the farm, he
lost his wife through the protracted, final
settlement. Meanwhile, this guy had been
warned by the bin company just a few
months before. He was given decals to put
on his customer's bins, which warned that
there was a problem. He just ignored it.
He never went out and contacted anybody.

The other thing relating to that is when we
took the deposition of one of the engineers

Surgeon General's Conference on Agricultural Safety and Health - 1991

369


Intervention - Worker Protection from Environmental Hazards

for the bin company. He had been with
the company for over 30 years. He had
been in every phase of it, and you would
think he would know what was going on.
He was asked, "On this warning we are
talking about, `Do not run the fans during
icy conditions,' define what that meant?"
He said "I don't know."

So, here is a company that charges an
engineer with writing up a warning label.
He has had 30 years experience with the
company.

He writes a warning label that he cannot
even interpret, but they can stick it on
their manuals or out on the bin and say,
"Okay, it is up to you, farmer, to guess
what this means." They think they are in
the clear. It is things like that, which real-
ly burn me up.

CONSULTATION

Sometimes you run into, "That Product B
is no good." You ask them where they get
their information. "Oh, the salesman for
Product A said so."

I think one of the problems in agriculture
is there are very few independent consul-
tants or consulting engineers who have
been able to look at a situation and make
recommendations regarding some of these
factors.

Another thing that was brought up is that
we are dealing with, especially traditional
agriculture, a farmer who feels that he is a
jack of all trades. That being the case,
they try to do most of their own repairs a
lot of times, sometimes not with the best
results.

As an example of designing out problems,
about 10 or 12 years ago a fellow came to

370

me. He wanted a tank designed for ma-
nure storage. I changed his original con-
cept. There are half-inch diameter steel
cables that are enclosed within panels that
go all the way around the tank. There is a
special jacking panel where they come out.

One of the problems you can run into on
these tanks is the build-up of ice. In this
particular case it was a couple or three
feet of ice. All of a sudden a big sheet of
ice collapsed. That is a lot of force.
There have been metal tanks that I know
of that have just split in those situations.

In this case, there was a tremendous noise.
The guy went running off and two fellows
who were near the tank went running off.
A guy coming back from the field could
not figure out what was going on. They
thought the thing was collapsing. Instead
of collapsing it held together. That is what
factors of safety are for in design.

The panels had holes that are cast right in
the panels. What happened was the top
cable snapped; when you have 20 tons of
force, a cable snaps. I thought back to the
time when a friend of mine from high
school was in the Navy over in Viet Nam
on an aircraft carrier, and when one of
those cables snapped, it cut him in half. I
thought, well if you are designing a tank
like that, if you have cables on the outside
and a cable broke, what would happen.

In this case it was completely contained.
Nothing happened. In fact, they went on
and used it for a year or so, and then the
guy came back and threaded in a new
cable. So, that is just one example of how
problems can be designed out.

I guess from this standpoint, we have
heard about the gas from livestock causing
problems. We have to decide whether we

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A Consulting Engineer's Perspective, May 2, 1991

are going to encourage and train people or
are we going to hit them with regulations
and say that, you know the Ten Command-
ments or whether it is going to be the
Golden Rule. How would you do it so you
would not cause problems for somebody
else?

TECHNOLOGY

The other thing that is affecting this whole
situation of injuries and accidents is misap-
plication of technology. After my sopho-
more year in 1968, I worked during the
summer for a company in Burlington,
Iowa.

I remember being impressed at that time
as I was putting together drawings from
several different departments of a new
crawler. One of the other engineers was
walking by the drafting table, when he
stopped and looked. He never said a thing
to me. I was just a student trainee that
year. Then he looked at that again. He
went and got some other fellows.

They looked at it again, and they had a
conference. I did not know what was go-
ing on. It turns out that when I had drawn
in where the track would go around near
the operator's platform, there had been a
situation one time, where somebody had
been injured or a problem had come up
with clearance between the track and the
platform for the operator. They caught it,
and the design was changed to rule out
that problem.

You always have to deal with the question
that came up yesterday that if somebody
does suggest a change, who is going to pay
for it, and whether or not we try to
squeeze it out of the price that the farmer
gets for the product that he sells. In any
case, something needs to be worked out
because we do need him and her. If not,
food prices are going to be a lot higher,
and I think our way of life is going to be
changed quite a bit.0

Surgeon General's Conference on Agricultural Safety and Health - 1991

377


Surgeon General's Conference on AgrfculWa/ SaMy and Health
FARM&E 2000 o A Natlonel Coalition Ibr Local Action
Convened by the National lnetitute Ibr Oecupationai Sakty and Health
April 30 - May 3, 1991, Des Moines, Iowa

AN EXTENSION SPECIALIST'S PERSPECTIVE

   By Rollin D. Schnie&r, MS.
Extension Safety Specialist, Universtty of Nebraska

Dr. David S. Pratt: Rollin Schnleder has been in safety In American agriculture for 35 years. He is
one of the real pioneers and leaders. He is someone I cettalnly have admired over a long period of
time. Right now, he Is professor of Blosystems Engineerlng at the Unlverslty of Nebraska in Lincoln.
For 35 years, he has been on staff there. He has helped to write the hlstory of the Emergency
Medical System (EMS) program and the communications program In Nebraska. Dr. Schnieder has
written a great deal and been a major contributor to the understandlng of safety in agriculture. He
has also been collaborating with the people at the medical center in a way that Is allowing the two
branches at the university, in both Lincoln and Omaha, to collaborate with each other. Although the
medical college and Lincoln campus have worked together before, they are hoping to blaze new
trails. Today, Roilin Is going to speak to us as only he can. He will speak to us from An Extension
Safety Specialist's Perspective on this issue with a long history. Help me welcome
Mr. Roiiin Schnieder:

Dr. Pratt asked me to show this book to
you. In 1965, when the Department of
Transportation (DOT) was coming into
being we had 16 parts of DOT. One of
them was clean-up, One was the trans-
portation of people.

I can remember vividly the night in Sep-
tember of 1965, in the Cornhusker Hotel,
where we had a group of about twenty
people that were looking at the EMS pro-
gram and also the communications pro-
gram. Looking at EMS, in 1983 or 1984, I
told Dr. Ken Kimball, who was on this
committee, and Brigadier General Don
Penterman, who was looking at com-
munications, that:

We ought to write a book of what we
know about the history of EMS and com-
munications in the state.

There is only one other that I am aware of
in the nation. That is Wyoming. They
have a 190-page pictorial booklet. We put
ours in the form of writing.

There will be another book coming out
soon, probably 165 pages on farm accident
rescue. The American Academy of Ortho-
pedic Surgeons will publish it.

Dave Morgan from our staff, who is a
tractor test engineer and EMT instructor
in his own right, and I wrote this up.
Hopefully, this will be published by late
fall.

I am going to use a little different
variation from Ray's (Crammond) presen-
tation. I was most impressed with the
speakers that we had yesterday. I wanted
to add a few things as I sat there and lis-
tened.

So we did.

STATISTICS

This came out in 1985. It is a 264-page
manual on the whole history.

Dr. Hoghind spoke of statistics. He said
that there is a variation in statistics. You
had better believe me; there is a variation

372

Papers and Proceedings


in statistics. When you try to compare the
United States to Sweden to Denmark to
England to Germany, there is a real varia-
tion.

Dr. Gary Erisman did not say it, but he
and I have talked about this before.
Gary's point was that we talk about the
number of fatalities and the number of
injuries we have. He has told me that
"there are a lot more out there than we
know about." I feel exactly the same way.

In 1978 or 1979, after OSHA had been in
force for a few years, we had some people
comment, "My gosh, here we have got
OSHA and the statistics are going up."
No, they were not going up. They were
out there all the time.

People were just finding them. Gary and I
were advisors to OSHA from 1972 to 1976
so we had a good background on what was
taking place.

I remember that there was a new safety
specialist in Colorado. He called and
wanted to know if I would train him.

A few months later Sid said, "I am glad we
don't have the problem that you have in
Nebraska." I replied, "Sid, you have it in
Colorado. I know my problem. I am
going after the figures. You are not."

That is what happens. We also know that
some of these statistics are hidden. So, I
appreciate the comments regarding statis-
tics.

I was back at a meeting with John Pollock
and Dr. Pratt a few years ago. They had
reinstituted a farm injury study in New
York.

An Extension Specialist's Perspecthre, May 2, 1991

It amazed them to know that they had 35
fatalities in that first year of their study.
They were working with the Farm Bureau
in New York. They could not believe that
they had that many.

They were there all the time. They just
found out where they were. When you live
in a little community, you might hear
about the one in your county. You do not
hear about the ones statewide.

I can tell you that we have had 853 fatali-
ties in Nebraska from 1969 through the
present day. These are broken down by
the type of accident. Even then I am sure
that I might have missed a few.

Sometimes the victim gets transported
across state lines to medical facilities. It
may be a Nebraskan who is taken to a
Sioux City Hospital. That report comes
into Des Moines and it eventually gets
back to Lincoln.

Sometimes there is a delayed one and I
may not find it. So even I miss a few of
those. So, to Gary and Sverker Hoghind, I
appreciate your comments.

DESIGN

John Etherton is sitting back here. It is
John's job to come up with a statement
about roll-over protective structures, retro-
fitting.

There are a lot of people who say, "Let's
retrofit everything." This all sounds well
and good, but you change a tractor when
you do that.

For example, when we came out with the
roll bar, people were complaining about
the noise. You had the tuning fork con-
cept or added noise. I had a lot of calls,

Surgeon General's Conference on Agricultural Safety and Health - 1991                373


Intervention - Worker Protection from Environmental Hazards

What can we do?" We can dampen.
Some were putting sand down in the up-
rights to dampen the noise. Some were
putting loaded springs across to dampen
them, anything to get this noise down.

You can change characteristics of tractors.
You have to realize that a lot of the equip-
ment that we have in agriculture is not
totally designed. This is what Ray
(Crammond) was saying.

For example, the first totally designed
tractor came into being in 1971. We had
tractors that were designed; then we had
after-market cabs put on. That was not a
part of the design and there were some
noise problems.

You have to realize that a lot of the
equipment that we have in agriculture is

In 1971, there were two totally designed
tractors. One was a Deere, the other one
was Allis-Chalmers. They designed the
whole unit and had the cab as part of it.
They came in with a noise level of 80 or
less. It was right around 80 db at that
time. This was a whole new concept.

Now those tractors are running down
around 74 db, because they are designed
as a total unit.

This concept is true with other machinery.
I was involved in a lawsuit 28 or 29 years
ago, where a little boy lost a leg in an
auger. The auger was built by one com-
pany; another part was built by another
company. '

There were four people who went together
on this, and they all thought, `The other
one is going to put the safety features on."
Nobody did. You have to look at the
totally designed system.

We can look at anhydrous ammonia as
another example. You buy the running
gear, order so many at a certain price.
You buy the tank, order so many at a
certain price. You buy the pop-off valves,
so many at a certain price. Put a hose on.
They are all component parts.

One of those is the weakest part of the
system, and so we have problems. We
have to look at the total problem, not
components.

There is another thing we have to realize.
It was alluded to yesterday. I do not know
if it was Gary (Erisman) or Sverker
(Hoghind). Many times engineering is
overruled by advertising. I have seen this.

We are going to put a product on the
market. It is maybe not what we want, but
we are going to get it out there. I think of
one tractor whose advertising said, "We're
going to boost the pump up a little bit to
get two more horsepower at the drawbar."
When they did this, they also got more
noise out of it.

Advertising wanted the horsepower; they
did not care much about the noise. The
engineers were put at a disadvantage.

They can do their best design, but they are
put at a disadvantage if marketing makes
the final decision. I think Steve Konz
alluded to this in his presentation this
morning.

374

Papers and Proceedings


PROTECTION

Dr. Richard Fenske yesterday talked about
protection. I am going by a few comments
that people made. He talked about the
closed tractor cabs for pesticide protection.
This is good.

In fact, Cornell did some work on this in
1978 or 1979. It is of benefit. The thing
we have to watch is that if people mix the
pesticide and then get in the cab, they take
it in on their clothing. I have been on a
pesticide-training program since 1978.

Our recommendation is that if you have
two people, have one do the mixing and
one do the application. Or take your
clothing off before you get in the cab if
you are working alone.

There is another thing that Richard talked
about yesterday. It regards a question that
I get all the time. How do we tell when
the cartridge or the canister is loaded? I
give the same answer that he gave yester-
day.

Right now we talk about time and con-
centration. We can look at acidity, and we
take litmus paper and test for acidity.

Is there some way that an engineer, or
epidemiologist, or somebody could design
a cartridge or a canister that when the cat-
ion/anion process gets to 90 percent being
loaded (somewhat like the working device
for telling when the turkey is done), it
could send up a little flag or a change in
color? It is a very simple process, and
maybe there is a way that we could take
care of this question.

I made one comment. There was a ques-
tion yesterday about coveralls in the green-

An Extension Specialist's Perspective, May 2, 1991

house and the material going through.
Nothing was said about an apron.

One of the things we point out in our
program is the need for hand protection,
eye protection, and apron protection. We
know that the hands constitute a major
point of entry in to the body. The label
still reigns supreme. It must be followed.

Another thing came up about re-entry into
fields. We have had some close problems
(poisoning) with county agents. We have
had farmers who have asked county agents
to look at their field for insects. I think of
one that we had where the farmer did not
tell the agent that the night before he had
sprayed his field with parathion.

This has a 4%hour re-entry. The agent
who was asked to go in there is 6 feet 5
inches and weighs 300 pounds. He was
sick when he came out of that field. He
was going to head back home. He did not.
He sat along the roadway for about 2
hours.

We had another instance. A young man
was asked to go into the field. His situa-
tion was almost identical.

I think back when I was a young lad. Dad
and I would go along the back roads, and
if we saw a cornfield that looked good, we
would want to walk out and see how that
corn was. We would walk out in that field
and check the neighbor's corn. I would
never think of doing that today because
you do not know what the plants might
have on them.

OTHER PROBLEMS

This morning we heard a talk about vec-
tors that was very interesting. We do not
have some of those problems.

Surgeon General's Conference on Agricultural Safety and Health - 1991               375