John W. Bartok, Jr.
University of Connecticut Cooperative Extension System
Concern for applicator safety has increased during the last
few years as more information on the effects of pesticides
on the body become known. As awareness increases so has the
development of better protective equipment. One of the most
recent developments is the pesticide protective helmet that
provides filtered air under positive pressure (see Figure
1).
The
helmet overcomes common problems with other face protection.
Face masks and respirators frequently leak as they do not
readily adjust to fit all sizes and shapes of heads. For workers
with eyeglasses, beards, mustaches or long hair, a tight seal
is almost impossible. The protective helmet on the other hand
protects the head, nose, eyes, mouth, ears and respiratory
system.
Weighing
from 2 to 4 pounds, the helmet is molded of fiberglass usually
with a double shell to give air distribution to the face area.
Suspension on the head is from an adjustable band. Some manufacturers
provide a chin strap to help stabilize the helmet so that
it moves with the head.
Wide
angle vision is provided through a clear face shield. Made
of tough polycarbonate, the shield is abrasion resistant and
impact proof.
Air
is supplied to the helmet through a flexible hose from a blower
unit that is worn on a belt. Air flow is regulated with several
motor speeds on the blower. Helmet models for greenhouse application
operate on battery power. Some manufacturers use rechargeable
nickel-cadmium batteries with a 4 to 8 hour operating cycle.
These will give about 2 years of service under normal use.
Others use a sealed lead-acid battery. A charger that connects
to a 115 volt power supply is included with the unit. Where
the pesticide application is limited to operating field sprayers
such as in nursery operations, one manufacturer (KASCO) supplies
a unit that is powered by the tractor electrical system.
The
filter is the heart of the system. The A/P filter, standard
for most systems, can be used in areas where organic vapors,
pesticides, dusts, fumes and mists are being applied. It consists
of two parts. The gas filter (A) excludes organic vapors and
pesticides. The dust portion (P) excludes dusts, aerosols
and mists. Other filters are available that can be used with
inorganic vapors and specific chemicals. There are no filters
available for use in atmospheres containing fumigants, car
on monoxide, natural gas or against organic vapors which generate
high heats of reactions.
Manufacturers
have their units tested to met NIOSH (National Institute for
occupational Safety and Health) standards. Be sure the unit
that you purchase has this approval. The cost for most systems
is from $500 to $600.
Operation
of the unit is simple. After placing the helmet over the head,
the drawstring is tightened to form a seal at the neck. Some
manufacturers have an adapter that attaches the helmet directly
to a protective suit. After placing the filter/blower unit around
the waist, the hose from the helmet is connected to the blower.
The airflow speed is selected next, then the visor is closed
to seal the unit. In most units the exhaust vents on the helmet
can be regulated to obtain the desired positive pressure.
To keep
the protective helmet system in good operating order the correct
storage and maintenance procedures should be followed. After
use the helmet shell should be cleaned with soapy water. Care
should be taken not to scratch the face shield. The efficiency
of the visor seal can be easily checked when the unit is off
the head by pulling the drawstrings until the collar is completely
sealed. With the blower attached the unit is operated. If
the collar inflates quickly, it means that the helmet is sealed
properly. If not there may be a leak in the visor seal.
If the
unit is equipped with Ni-Cd batteries, they should be stored
discharged and then charged just before use. A lead-acid battery
should be kept charged.
The
filters used in these units have a limited life, usually 6
months. Even if unused and sealed in their original package,
they have to be discarded if the expiration date is passed.
Filters cannot be washed, blown out or restored. On some units
an indicator is used to warn the operator when a filter looses
its effectiveness. Others depend on the operator detecting
a failure or plugging by smell, taste, or irritation to the
eyes, nose or throat.
To keep
the warranty in effect, replacement parts should be obtained
from the manufacturer or authorized dealer. Use of other than
exact replacement parts voids the NIOSH approval.
While
selection and wearing of respiratory protective equipment is
of prime importance in the application of many toxic and hazardous
pesticides, there is need for other body protection. Non-absorbent
neoprene gloves should be worn at all times when handling, mixing
or applying pesticides. Footwear that is resistant to chemicals
and cleaned to prevent slippage will protect the feet.
Disposable
Tyvek coveralls are a good choice for body protection. They
can be worn over existing garments and eliminate the need
to wash contaminated clothing. These are available from greenhouse
or spray equipment suppliers.
Disclaimer
and Reproduction Information: Information in NASD does not represent
NIOSH policy. Information included in NASD appears by permission
of the author and/or copyright holder. More
NASD Review: 04/2002
This document was
produced by the Connecticut Cooperative Extension System, College
of Agriculture and Natural Resources, The University of Connecticut,
1376 Storrs Road, Storrs, CT 06269-4036, (203) 486-4125.
John W. Bartok, Jr. Extension Agricultural Engineer, Connecticut
Cooperative Extension System
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