Transcript Silicosis - A Primer for Prevention

Silicosis - A Primer for
Workplace Prevention
The History of Silicosis
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Reports of workers dying of silicosis - a disabling,
non-reversible and sometimes fatal lung disease
caused by inhaling dust containing silica - date back
to ancient Greece.
During the Industrial Revolution of the late 1800’s
and early 1900’s, as farmers and immigrants took
jobs in dusty foundries, mills and mines, exposures to
silica significantly increased and consequently so did
the disease’s prevalence.
The History of Silicosis
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Studies in the 1910’s showed high rates of silicosis
among the lead and zinc miners of Oklahoma, Kansas
and Missouri where rocks and ores have been known
to consist of more than 95% of silica. One study in
1915 showed that more than half of the 700 zinc
miners sampled had silicosis.
The History of Silicosis
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During the 1930’s outrage over silicosis heightened
with the advent of the Hawk’s Nest incident, which
has been called “America’s worst industrial disaster”.
During a hydroelectric project through a West Virginia
mountain, workers who were not provided any
respiratory protection were exposed to very high
contents of silica. Although it was current knowledge
that the exposure to dust containing silica was known
to be potentially fatal, sponsors’ of the project did
nothing. Estimates of the number of deaths
associated with this exposure range from 66 to a
researcher’s study count of more than 700.
The History of Silicosis
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Soon after the Hawk’s Nest incident, then Secretary
of Labor, Frances Perkins declared war on silicosis
after a national conferences in 1936 and 1940 a film
entitled “Stop Silicosis” was issued to help elevate the
national agenda and promote the need to prevent
silicosis.
The History of Silicosis
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Almost 30 years later in response to the growing
concern regarding workers’ safety, several new
federal laws were passed in the late 1960’s and early
1970’s adopting rules that limited the exposure to
silica dust.
Since that time deaths due to the exposure of
silicosis have declined, however, the disease still
claims more than 250 American workers and
disabling countless others.
National Initiative
to Prevent Silicosis
1997 National Conference to Eliminate
Silicosis - March 25th & 26th, 1997
 OSHA-MSHA-NIOSH Partnership
 American Lung Association
 Share Information
 Share Statistical Information
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What is Silicosis?
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Silicosis is a disabling, nonreversible and sometimes
fatal lung disease caused by overexposure to
respirable crystalline silica. Silica is the second most
common mineral in the earth’s crust and is a major
component of sand, rock and mineral ores.
Overexposure to dust that contains microscopic
particles of crystalline silica can cause scar tissue to
form in the lungs, which reduces the lungs’ ability to
extract oxygen from the air we breathe. Typical sand
found at the beach does not pose a silicosis threat.
Types
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There are three types of silicosis, depending upon the
airborne concentration of crystalline silica to which a
worker has been exposed:
– Chronic Silicosis usually occurs after 10 or more
years of overexposure
– Accelerated silicosis results from higher exposures
and develops over 5-10 years.
– Acute silicosis occurs where exposures are the
highest and can cause symptoms to develop
within a few weeks or up to 5 years.
Where Do You Find
Silica Dust?
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Here are some examples of the industries and activities that
pose the greatest potential risk for worker exposure:
– construction (sandblasting, rock drilling, masonry work, jack
hammering, tunneling)
– mining (cutting or drilling through sandstone and granite
– foundry work (grinding, moldings, shakeout, core room)
– ceramics, clay, and pottery
– stone cutting (sawing, abrasive blasting, chipping, grinding)
– glass manufacturing
– agriculture
– shipyards (abrasive blasting)
– railroad (setting and laying track)
– manufacturing and use of abrasives
– manufacturing of soaps and detergents
What Are the Symptoms &
Complications of Silicosis
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Chronic silicosis, the most common form of the disease, may go
undetected for years in the early stages; in fact, a chest X-ray
may not reveal an abnormality until after 15 or 20 years of
exposure. The body’s ability to fight infections may be
overwhelmed by silica dust in the lungs, making workers more
susceptible to certain illnesses, such as tuberculosis. As silicosis
progresses, you may exhibit one or more of the following
symptoms:
– shortness of breath following physical exertion
– severe cough
– fatigue
– loss of appetite
– chest pains
– fever
What Can Employers Do to
Prevent Silicosis?
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Make a commitment to prevent silicosis at your worksites.
Comply with OSHA and MSHA regulations on respirable
crystalline silica. If your employees are overexposed, reduce
exposure levels through the use of engineering controls. While
these controls are being installed, or if they are being repaired,
provide appropriate respiratory protection.
Perform air monitoring of worksites as needed, and when
required by law, and take corrective action when silica levels are
excessive. Monitoring provides a basis for:
– selecting and ensuring the effectiveness of engineering
controls
– selecting proper respiratory protection
– seeing if work practices to reduce dust levels are effective
– determining if a medical surveillance program is necessary
What Can Employers Do to
Prevent Silicosis?
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Install and maintain engineering controls to eliminate or reduce
the amount of silica in the air and the build-up of dust on
equipment and surfaces. Examples of controls include: exhaust
ventilation and dust collection systems, water sprays, wet
drilling, enclosed cabs, and drill platform skirts. Practice
preventive maintenance because the extreme abrasiveness of
the silica dust can damage the systems you install.
Substitute less hazardous materials than crystalline silica for
abrasive blasting, when possible. Try to use automatic blast
cleaning machines or cabinets that allow operating the
machines from outside using gloved armholes.
What Can Employers Do to
Prevent Silicosis?
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Supply vacuums with high-efficiency particulate air (HEPA)
filters, and advise employees to vacuum, hose down, or wet
sweep work areas, instead of dry sweeping
Train workers about health effects, engineering controls and
work practices that reduce dust, the importance of maintenance
and good housekeeping, as well as on the proper type and
fitting of respirators. Make sure they know what operations and
materials present a silica hazard.
Establish a written respiratory protection program. Outfit
employees with appropriately selected, properly fitted, approved
respirators when engineering controls alone are insufficient to
keep exposures within safe levels. Be sure respirators are kept
clean and properly maintained and that employees are trained
in their use.
What Employers Can Do...
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Provide medical examinations for employees who may be
exposed to respirable crystalline silica, as recommended by
NIOSH, and have X-rays read by a specialist in just diseases.
Develop a plan for reducing exposures of employees whose Xrays show changes consistent with silicosis.
Report all cases of silicosis to state health departments and to
MSHA, and record cases on OSHA logs, as required.
Post warning signs to identify work areas where respirable silica
is present.
What OSHA and MSHA
Regulations Apply?
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OSHA enforces a permissible exposure limit, which is the
maximum amount of airborne crystalline silica that an employee
may be exposed to during an eight-hour work shift.. That
amount is 10 mg/m(3) MSHA enforces its own exposure limits,
has rules requiring controls for drills, and requires air sampling
in certain situations.
Other relevant OSHA and MSHA regulations include: respiratory
protection, posting of warning signs, housekeeping,
recordkeeping or reporting of occupational illnesses, abrasive
blasting, personal protective equipment, and training. OSHA
has rules on hazard communication, safety and health programs
in construction, and access to employee exposure and medical
records.
What Can Workers Do to
Prevent Silicosis?
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Work with your employer to prevent silicosis at your worksite.
Use engineering controls installed by your employer to reduce silica
dust levels, and make sure they are properly maintained. Tell your
employer when they aren’t working properly.
Minimize dust by following good work practices, such as removing dust
with a water hose or vacuum with a high-efficiency particulate filter
rather than blowing it clean with compressed air, or by wet sweeping
instead of dry sweeping.
Suggest to your employer to substitute less hazardous materials than
crystalline silica for abrasive blasting.
Wear, maintain, and correctly use approved particulate respirators
when engineering controls alone are not adequate to reduce exposures
below permissible levels. Beards and mustaches interfere with the
respirator seal to the face, making most respirators ineffective.
If you must sandblast, use type CE positive pressure abrasive blasting
respirators.
What Can Workers Do to
Prevent Silicosis?
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Participate in air monitoring, medical surveillance, and training
programs offered by your employer or when required by law.
Talk to your employer, employee representative, or union if you
are concerned about the dust in your workplace. Ask for the
results of air sampling done at your worksite. You may also
contact the Occupational Safety and Health Administration
(OSHA) or the Mine Safety and Health Administration (MSHA).
As a reminder, whenever you work with toxic materials, it is
always a sound practice to:
– Change into disposable or washable work clothes at your
worksite, if possible; shower, where available; and change
into clean clothing before leaving your worksite.
– Avoid eating, drinking, or using tobacco products in work
areas where there is dust or other toxic materials.
– Wash your hands and face before eating or drinking.
Mine Safety and Health
Administration
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MSHA prioritizes health risks in metal and nonmetal mines and
allocates Agency resources according to ranking criteria
described in the attached excerpt from its Program Policy
Manual (“Sampling Policy for Airborne Contaminants and Nose”,
Volume IV, pp 3-7). These criteria specify how often the Agency
should sample mines based on their health hazards. The more
serious the hazard, the more often a mine is sampled. The
least hazardous mines are sampled only once every 5 years
unless a more serious problem is identified through an
inspection or employee complaint.
When the Agency Ranks a mine, it considers the history of
overexposure, the type of process, and the commodity. Ground
silica and industrial sand operations are always ranked “A”
requiring annual sampling. Among other mines with “A” ranking
are those with lead, asbestos, mercury, or cadmium as products
Sampling Policy for Airborne
Contaminants and Noise
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At least annually, enforcement personnel in each Metal and
Nonmetal office shall review a printout of the Personal Exposure
Data Summary (PEDS) listing samples taken at the mines in
their jurisdiction over the past 5 years. Based on this review
and all other relevant information, each mine shall be ranked
and sampled according to the criteria and frequencies indicated
(in Paragraph B). This policy applies equally to all mines, fulltime, seasonal, and intermittent.
In general, personal full-shift exposure samples shall be taken.
Miners shall be sampled for every contaminant to which they
are likely to be significantly exposed. “Significant” exposure is
one-half the permissible exposure limit (PEL). Citations are
issued for exposures in excess of 1.2 times the PEL.
Sampling Requirements
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Samples for the appropriate metallic elements (dust or fume)
are required where metal ores are mined and/or processed.
This includes by products, regardless of whether they are
recovered.
Samples for other minerals that have exposure limits of their
own (cristobalite, mica, talc, etc.) are required where such
minerals are mined and/or milled.
Where process chemicals are used, gases and vapors associated
with the chemical(s) must also be sampled. Samples for
particulates, toxic gases, and vapors are required wherever
miners are likely to experience significant exposure.
Minimum Sampling
Requirements
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The number of employees does not include office workers or
workers who “come and go” from the property; it does include
laborers, maintenance workers, technical and managerial
personnel, etc., whose tasks are performed throughout the
facility.
A rank shall be assigned to each mine for respirable crystalline
silica and for noise. Ranking for other contaminants is required
when there is an exposure limit for the mined ore or mineral, its
byproducts or primary process reagents, or whenever the
contaminant meets a criterion in Rank A or B.
Workplace Silicosis
Prevention Program
Management Commitment
 Exposure Monitoring
 Medical Surveillance
 Analysis and Evaluation of Data
 Awareness Training
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Risk Assessment
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Where are the Potentials for Silica Exposure?
What Part of the Operation has the Highest Potential
for Exposure?
How and Why are Employees Exposed to Silica?
What Engineering Controls are In Place?
What Does OSHA or MSHA Data Regarding Exposure
Indicate?
What is the Typical Length of Service of Employees
who have the Highest Potential to be Exposed to
Silica?
Determine if...
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If there is a Real Risk of Silicosis in your Company
Where the Highest Potential for Silica Exposure is
Located
How many Employees need to be in this Program?
The Effectiveness of Current Engineering Controls
The Contributing Factors that may Affect Employee
Exposure to Silica
The Amount of Awareness Training that must be
Conducted
The Potential for Compensatory Health Claims
Prepare a Strategy
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Determine Scope for Exposure Monitoring and
Medical Testing
Describe a Process Used to Address Out-ofCompliance Conditions
Develop Pre-Employment Screening Process
Develop Awareness Training Model
Develop Accurate Costs of Implementation
The Benefits
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Increased Awareness and
Prevention of Lung Disease
through Early Detection
Improved Customer, Employee,
and Community Relations
Management of Claims under
Workers’ Compensation
Improved Compliance with
State and Federal Regulations
Improved Production and Cost
Efficiency of Operation
Where Can You Get More Information
on Preventing Silicosis?
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Call 1-800-35-NIOSH. Select option 2, then option 5
for a complete package of information on silicosis
prevention.
For free help in establishing or improving your safety
and health program, small businesses can contact the
OSHA Consultation Program in their state or contact
the Small Business Administration at
1-800-REG-FAIR (734-3247) or www.sba.gov/regfair
Contact the Mine Health and Safety Academy in
Beckley, West Virginia at (304) 256-3257 or them at
(304) 256-3368 (fax).