Silicosis - A Primer for Workplace Prevention

1
Silicosis - A Primer for Workplace Prevention
2
The History of Silicosis

• 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
  1800s and early 1900s, as farmers and
  immigrants took jobs in dusty foundries, mills
  and mines, exposures to silica significantly
  increased and consequently so did the diseases
  prevalence.

3
The History of Silicosis

• Studies in the 1910s 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.

4
The History of Silicosis

• During the 1930s outrage over silicosis
  heightened with the advent of the Hawks Nest
  incident, which has been called Americas 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
  researchers study count of more than 700.

5
The History of Silicosis

• Soon after the Hawks 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.

6
The History of Silicosis

• Almost 30 years later in response to the growing
  concern regarding workers safety, several new
  federal laws were passed in the late 1960s and
  early 1970s 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.

7
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

8
What is Silicosis?

• 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
  earths 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.

9
Types

• 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.

10
Where Do You FindSilica Dust?

• 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

11
What Are the Symptoms Complications of Silicosis

• 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 bodys 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

12
What Can Employers Do to Prevent Silicosis?

• 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

13
What Can Employers Do to Prevent Silicosis?

• 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.

14
What Can Employers Do to Prevent Silicosis?

• 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.

15
What Employers Can Do...

• 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 X-rays
  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.

16
What OSHA and MSHA Regulations Apply?

• 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.

17
What Can Workers Do to Prevent Silicosis?

• 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 arent 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.

18
What Can Workers Do to Prevent Silicosis?

• 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.

19
Mine Safety and Health Administration

• 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 or by-products.

20
Sampling Policy for Airborne Contaminants and
Noise

• 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, full-time, 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.

21
Sampling Requirements

• 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.

22
Minimum Sampling Requirements

• 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.

23
Workplace SilicosisPrevention Program

• Management Commitment
• Exposure Monitoring
• Medical Surveillance
• Analysis and Evaluation of Data
• Awareness Training

24
Risk Assessment

• 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?

25
Determine if...

• 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

26
Prepare a Strategy

• Determine Scope for Exposure Monitoring and
  Medical Testing
• Describe a Process Used to Address
  Out-of-Compliance Conditions
• Develop Pre-Employment Screening Process
• Develop Awareness Training Model
• Develop Accurate Costs of Implementation

27
The Benefits

• 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

28
Where Can You Get More Informationon Preventing
Silicosis?

• 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 [phone] or them
  at
• [phone] (fax).