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RESPIRATORY
PROTECTION
What is a Respirator?
A
respirator is a protective device that covers the nose and mouth or the
entire face or head to guard the wearer against hazardous atmospheres.
Respirators may be:
> Tight-fitting—that is,
half masks, which cover the mouth and nose and full facepieces that cover
the face from the hairline to below the chin; or
> Loose-fitting, such as
hoods or helmets that cover the head completely. In addition, there
are two major classes of respirators:
> Air-purifying, which remove
contaminants from the air; and
> Atmosphere-supplying, which
provide clean, breathable air from an uncontaminated source. As a general
rule, atmosphere-supplying respirators are used for more hazardous exposures.
When do employees need to wear respirators?
Employees need to wear respirators whenever engineering and work
practice control measures are not adequate to prevent atmospheric contamination
in the workplace. Strategies for preventing atmospheric contamination
may include enclosing or confining the contaminant-producing operation,
exhausting the contaminant, or substituting with less toxic materials.
Respirators have their limitations and are not a substitute for effective
engineering and work practice controls. When it is not possible to use
these controls to reduce airborne contaminants below their occupational
exposure levels, such as during certain maintenance and repair operations,
emergencies, or when engineering controls are being installed, respirator
use may be the best or only way to reduce worker exposure. In other cases,
where work practices and engineering controls alone cannot reduce exposure
levels to below the occupational exposure level, respirator use is essential.
Where respirators are required to protect worker health, specific procedures
are necessary to ensure the equipment’s
effectiveness.
Respiratory Protection Program
Respirators and a written respirator program are required by
OSHA whenever respiratory protection is selected by the company to reduce
air contaminants below the Permissible Exposure Level. A respirator program
should include the following elements: > Physician's
examination to determine the worker's capability of wearing a respirator.
> Program implementation and annual re-evaluations.
> Written standard operating procedures for the selection and use of
respirators.
> Fit testing.
> Purchase of respirators and/or filters for each atmospheric need.
> Purchase of cleaning materials, filters, pre-filters, canisters and
spare parts.
> Documented employee training on respirator use and limitations.
> Equipment inspection, cleaning, maintenance and storage procedures
and records.
> Work-area monitoring to establish degree of exposure and type of
respirator needed.
> Maintenance of air quality for supplied-air devices, compressors
and self-contained breathing apparatus (SCBA) devices. The first
step in determining if a respirator program is necessary is to evaluate
the hazard (level of contaminants in the air and/or the work processes
involved, such as spray painting, abrasive blasting, etc). If contaminant
levels exceed the PEL (Permissible Exposre Limit), first evaluate and
implement suitable engineering controls that will lower the level of contaminants
below the PEL, if feasible. Then, careful selection of respiratory protection
and fit testing is required. A competent
person must continue to monitor the worksite, and evaluate the need for
a respirator program whenever exposures change. New exposures could be
due to different chemical uses, changes in work methods and processes,
or whenever chemical spills occur. Additional employee training may also
be necessary at this time. How
are work areas monitored ?
Employers must maintain surveillance of the work area conditions and the
degree of worker exposure or stress—a combination of work rate,
environmental conditions, and physiological burdens of wearing a respirator.
Changes in operating procedures, temperature, air movement, humidity,
and work practices may influence the concentration of a substance in the
work area atmosphere. Employers must periodically monitor these factors
as they affect air contaminant concentrations. In instances where work
is of such short duration that it takes longer to do the test than the
job, reasonable estimates of exposure are allowable. In situations where
the environment is or may be immediately dangerous to life or health,
employers must ensure that one or more employees are located outside the
dangerous environment. These employees must maintain visual, voice, or
signal line communication with employees in the IDLH atmosphere.
In interior structural firefighting situations, employers must ensure
that at least two employees enter the structure and remain in visual or
voice contact with one another at all times. Also, at least two employees
must be located outside the fire area to provide effective emergency rescue.
All workers engaged in interior structural firefighting must use SCBA. How
do you make sure the respirators fit properly?
Different types of respirators and even different brands of the same type
of respirator have different fit characteristics. No one respirator will
fit everyone. Some employees may be unable to get an adequate fit with
certain respirator models of a particular type of respirator. This is
why employers must provide a sufficient number of respirator models and
sizes to ensure that every employee can select an acceptable respirator
that fits properly.
Corrective eyeglasses worn by employees also present a problem when fitting
respirators. Special mountings are available to hold corrective lenses
inside full facepieces. A qualified individual must fit the facepiece
and lenses to provide good vision, comfort, and proper sealing.
Tight-fitting respirators cannot provide proper protection without a tight
seal between the facepiece and the wearer’s face. Consequently,
beards and other facial hair, the absence of normally worn dentures, facial
deformities, or jewelry or head gear that projects under the facepiece
seal can also seriously affect the fit of a facepiece. To ensure proper
respiratory protection, check the facepiece each time you wear the respirator.
You can do this by performing either a positive-pressure or negative-pressure
user seal check. Detailed instructions for performing these user seal
checks are in Appendix
B-1 of the OSHA respiratory protection standard.
Fit testing is required for tight-fitting facepiece respirators. You can
test the effectiveness of the fit of the facepiece two ways: qualitatively
and quantitatively. Qualitative fit testing involves the introduction
of a harmless odoriferous or irritating substance into the breathing zone
around the respirator being worn. If no odor or irritation is detected
by the wearer, this indicates a proper fit. Quantitative fit testing offers
more accurate, detailed information on respirator fit. While the wearer
performs exercises that could induce facepiece leakage, a fit testing
instrument numerically measures the amount of leakage into the respirator.
This testing can be done either by generating a test aerosol as a test
atmosphere, using ambient aerosol as a test agent, or using controlled
negative pressure to measure any leakage. Detailed instructions for performing
qualitative and quantitative fit testing is contained in Appendix
A of the OSHA respiratory protection standard. How
do you inspect and take care of respirators?
It is important to inspect all respirators for wear and tear before and
after each use, giving special attention to rubber or plastic parts that
can deteriorate or lose pliability. The facepiece, headband, valves, connecting
tube, fittings, and cartridges, canisters or filters must be in good condition.
A respirator inspection must include checking the tightness of the connections.
Users must inspect SCBAs at least monthly and ensure that air and oxygen
cylinders are fully charged according to the manufacturer’s instructions.
The inspection should include a check of regulator and warning devices
to ensure their proper function. Employers must keep records of inspection
dates and findings. Users should replace chemical cartridges and gas mask
canisters as necessary to provide complete protection, following the manufacturer’s
recommendations. In addition, they should replace mechanical filters as
necessary to avoid high resistance to breathing.
Only an experienced person is permitted to make repairs, using parts specifically
designed for the respirator. This person must consult the manufacturer’s
instructions for any repair and no attempt should be made to repair or
replace components or make adjustments or repairs beyond the manufacturer’s
recommendations. The employer must ensure that respirators are cleaned
and disinfected as often as necessary to keep them sanitary. In addition,
the employer must ensure that emergency-use respirators are cleaned and
disinfected immediately after each use. Respirators should be washed in
a detergent solution and then disinfected by immersing them in a sanitizing
solution. Cleaner-sanitizers that effectively clean the respirator and
contain a bactericidal agent are available commercially. The bactericidal
agent frequently used is a quaternary ammonium compound. Strong cleaning
and sanitizing agents and many solvents can damage rubber or plastic respirator
parts. Use these materials with caution or after consultation with the
respirator manufacturer. Users must store respirators in a way that protects
them against dust, sunlight, heat, extreme cold, excessive moisture, and
damaging chemicals. When packed or stored, each respirator should be positioned
to retain its natural configuration. Facepieces and exhalation valves
should rest in a normal position to prevent the rubber or plastic from
deforming.
Are medical evaluations necessary in order
to wear a respirator?
Workers assigned to tasks that require respirator use must be physically
able to perform the work while using the respirator. The local physician
or licensed health care professional (LHCP) will determine what health
and physical conditions are pertinent.The medical evaluation can be performed
by a physician or other LHCP by using a medical questionnaire or by a
medical examination that provides the same information as the questionnaire
provided in Appendix C of the OSHA standard. This evaluation must be done
before the employee is fit tested and uses the respirator in the workplace.
The employer must obtain a written recommendation from the LHCP for each
employee’s ability to wear a respirator. Additional medical evaluations
must be provided whenever health-care professionals deem them appropriate.
OSHA
Respiratory Guidance
OSHA Respiratory Standard
Training
Roster
Respiratory
Training Acknowledgement
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