Glen H. Hetzel
Virginia Cooperative Extension
Introduction
Choosing the Proper Equipment
Hazardous Sources and Their Contaminants
Places Where You Can Buy Respiratory Equipment
Respiratory Equipment Safety
In Case of Emergency
Who
Needs Respiratory Protection? |
-
THOSE working in dusty fields and buildings
-
THOSE handling moldy hay
-
THOSE working in silos
-
THOSE feeding or working with feedstuffs
-
THOSE working in corn silage
-
THOSE uncapping silos
-
THOSE cleaning grain bins
-
THOSE exposed to bird droppings or dust from animal
hair or fur
-
THOSE exposed to fish meal
-
THOSE applying agricultural chemicals (e.g. fertilizers
and pesticides)
-
THOSE working with toxic paints or solvents
|
If you
work in any one of these situations and do not wear some form
of respiratory protection, then you are placing yourself at
risk for serious lung diseases or even death.
You
may encounter a range of health problems from minor, temporary
discomfort caused by allergic reactions to fatal asphyxiation
depending upon the work environment and the hazards presented.
In each
of these cases, however, proper respiratory equipment can
protect you. Using such equipment is not the only means of
protection in all of these cases, but it is a practical solution
to safeguard and even improve your health.
Return
to Table of Contents
It
is important to wear respiratory equipment when working in a
hazardous environment, BUT IT MUST BE THE PROPER EQUIPMENT FOR
THE SPECIFIC TASK. Here are some things to keep in mind when
deciding which equipment to choose:
- Make
a list of operations and work sites where there is any kind
of contamination.
- List
any type of job where a lack of oxygen is a problem.
- List
the specific contaminants that correspond to the work site
and its jobs.
- List
how harmful the contaminants are - both potentially and/or
actually.
- List
the form of the contaminant material: dust, mist, spray,
gas, vapor, fume or some combination of these.
- Give
the concentrations of each contaminant.
- READ
ALL LABELS.
There
are several types of protective equipment available for all
tasks. They are broken down into two categories:
1. Air
Purifying. This type removes contaminants from the air. It
is only to be used where there is a sufficient oxygen supply.
This category includes: mechanical filter, chemical cartridge
and canister gas mask respirators.
2.
Oxygen Providing. This type provides oxygen for the user
in oxygen-deficient atmospheres. This category includes:
supplied-air respirators and Self-Contained Breathing Apparatus
(SCBA).
Air
Purifying Respiratory Protection
Mechanical
filter respiratory protection devices are commonly known as
dust masks. These simple filters commonly consist of a molded
filter designed to cover the nose and mouth. The filter is held
in place by one or two elastic straps that are stretched over
the head. Some of these type masks have a valve made into the
filtering substance to allow easier breathing. When the filter
becomes clogged, the complete unit is discarded. Units having
two straps fit better.
Dust
masks provide protection against airborne dust particles (chemical,
mineral, field or barn, chaff, pollen) and non-toxic paint
spray dusts. Sufficient levels of oxygen must be present in
the air to be filtered.
Chemical
Cartridge Respirators
Chemical cartridge respirators provide a higher level of protection
than dust masks. A soft rubber-like face piece (silicone) covers
the nose and mouth and contains valves to control air movement
through the device. A full face respirator also contains a lens
to cover the eyes. Replaceable cartridges containing activated
carbon are used to filter the incoming air. Prefilters are usually
installed on the outside of the cartridges. Elastic straps or
harness are used to hold the respirator snugly against the user's
face. A half mask covers only the nose and mouth of the user.
A full face respirator also includes an eye shield and covers
the entire face and eyes.
The
user must anticipate the type of hazard to be protected against
and purchase the correct cartridges. Most cartridges are designed
to provide protection for a specific type of chemical hazard
such as pesticides, ammonia, anhydrous ammonia, etc. Sufficient
levels of oxygen must be present in the air to be filtered.
Gas
Masks
Gas
masks have full face coverage. The filtering cartridge or canister
has a larger capacity than a cartridge type respirator. The
cartridge may be mounted on the face piece or at the end of
a flexible hose to allow mounting at the user's belt. Sufficient
levels of oxygen must be present in the air where gas masks
are used.
Gas
masks provide protection against pesticides, and often toxic
airborne materials. The greater capacity of gas mask cartridges
(canisters) allows longer working times in high levels of
contaminants than typical respirators.
Supplied-Air
Respiratory Protection Supplied-air
respirators provide fresh air from a remote source or from pressurized
tanks. The face pieces are similar to cartridge type respirators
or gas masks. The air may be supplied by a portable air compressor
or pressure tanks located up to 300 feet from the user. Compressors
must be located in a clean air area.
Supplied-air respirators can be used in confined spaces where
there is likely to be an inadequate level of oxygen.
SELF-CONTAINED
BREATHING APPARATUS (SCBA) is a type of respirator that has
full face coverage and an oxygen supply contained in a compressed
air tank carried on the users back. It can be used in oxygen
deficient areas and in hazardous atmospheres.
A self-contained
breathing apparatus can be used where ever the user must work,
such as in silos, manure pits, grain storage and fumigation
of structures.
Return
to Table of Contents
The
table below identifies some common hazardous sources and their
potential contaminants. It briefly summarizes situations where
you should use protective equipment to guard against dangerous
elements that may be present in the listed work environments--YOUR
work environment.
SILAGE
| MANURE
PITS
| CONFINED
POULTRY HOUSING
| CONFINED
HOG HOUSING
| PESTICIDES
|
CO2
nitrogen oxides
mold spores |
ammonia
methane
CO2
hydrogen sulfide |
DUSTS:
feathers and feather particles
dried skin material
dried fecal material
dried feed products
GASES:
ammonia
CO2
|
DUSTS:
hair and skin particles
dried feed products
dried fecal particles
GASES:
ammonia
CO2
hydrogen sulfide
methane
|
TOXIC:
fumes
gases
mists
dusts |
If you
are not sure which type of protective equipment is best for
the work you do, then ask the professionals who sell the various
products.
Return
to Table of Contents
You
can probably find most types of equipment at a safety supply
store, but farm supply stores and agricultural chemical suppliers
are also good sources. If any of these suppliers do not have
the equipment you need, they can likely order it for you or
tell you how you can order it yourself. Places that test-fit
the respiratory device to ensure a proper fit are the best places
to purchase your equipment.
For
information concerning the selection and use of respiratory
equipment, contact local agricultural stores, safety supply
stores, pesticide sales outlets, or the Virginia Cooperative
Extension.
Return
to Table of Contents
Respiratory
equipment can safeguard your health and save your life in any
hazardous air condition you may encounter. However, without
proper care and precautions when using such equipment, the device
you rely on could be ineffective. Here is a list of guidelines
and precautions every worker should follow when using protective
equipment.
- Individuals
should be completely familiar with equipment use. replacement.
care. cleaning and storage. Individuals should be properly
trained (SCBA requires special training for use).
- Individuals
should test equipment before every use. Follow the manufacturer's
instructions for properly testing equipment. If you are
using a respirator that has cartridges, you can use one
of two methods of testing:
1)
Positive Fit Check. Exhale while you cover the exhalation
valve with the palm of your hand -- if you feel air against
the skin of your face, there is a leak in the seal.
2) Negative Fit Check. Cover the cartridge(s) with your
hands and inhale -- if the mask is drawn tightly to
your face, there is no leakage.
- Make
sure the equipment properly fits you. Leakage defeats the
effectiveness of even the best respirator for the situation.
Testing the equipment will assure a proper fit.
- Individuals
should regularly clean and repair equipment.
- Individuals
should regularly change filter cartridges and pre-filters.
If you
are using filter cartridges and you notice a change in smell
or taste or you begin coughing, then the hazardous material
may be getting through the filter and it should be changed.
You should consider setting a regular changing schedule if
the contaminant cannot be noticed by the five senses.
If you
are using a pre-filter for more than five or six hours a day,
then you should change the filter daily. It is important to
change filter cartridges before breathing becomes difficult.
- Individuals
should store protective equipment in a clean, dry place
AWAY from work and chemical storage areas. Self-sealing
plastic bags are ideal for storing clean respirators.
- Individuals
must be fully capable of wearing protective equipment. If
you are not sure or do not know how a condition you may
have could affect proper use of equipment, check with your
physician. Some conditions which could cause problems are:
asthma, allergies, emphysema, high blood pressure, heart
disorder, claustrophobia or minor facial abnormalities.
- Buy
only certified respirators. Look for labels approved by
NIOSH or MSA that show an approval number.
- If
it is practical, assign respirators to individuals.
Caution:
Often, it is necessary to use other protective equipment and
clothing when using respiratory protective equipment, such
as special gloves, eye protection, and long sleeve shirts.
Return
to Table of Contents
In Case
of Emergency
If
you suddenly feel SICK, DIZZY or CANNOT BREATHE properly,
leave the hazardous area immediately. If someone
else is overcome by toxic gases:
|
Act QUICKLY but THOUGHTFULLY!
A
few minutes without oxygen can cause brain damage or death
for the victim-but without thinking about your own safety,
you could also become a victim.
CALL FOR HELP
Your additional local number:
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
Glen
H. Hetzel, Extension Agricultural Engineer Virginia Tech
|