Document 3egJZO7mok1yeJDzj2BOQmnQE
OREGON OCCUPATIONAL SAFETY AND HEALTH DIVISION DEPARTMENT OF CONSUMER AND BUSINESS SERVICES
PROGRAM DIRECTIVE
Program Directive: A-253 Issued: Jan 13, 2003 Revised: 2/12/2003
SUBJECT:
Special Emphasis Program (SEP) For Silicosis
REFERENCES:
OR-OSHA Field Inspection Reference Manual (FIRM) OR-OSHA Occupational Health Laboratory, Manual of Analytical Methods Preventing Silicosis and Deaths in Construction Workers, NIOSH Alert,
DHHS (NIOSH) Publication 96-112 Preventing Silicosis and Deaths from Sandblasting, NIOSH Alert,
DHHS (NIOSH) Publication 92-102
PURPOSE:
This directive describes policies and procedures for implementing a Special Emphasis Program (SEP) to reduce and eliminate the workplace incidence of silicosis resulting from occupational exposure to crystalline silica. This SEP includes inspections conducted in any industry or at any work site where the division determines that there is a potential worker exposure to crystalline silica.
BACKGROUND:
In May 1996, Federal OSHA initiated a SEP to address the high incidence of silicosis, a dust disease of the lungs, among workers occupationally exposed to crystalline silica. OR-OSHA has followed the federal Sep since 1997.
With this emphasis to reduce the incidence of silicosis, OR-OSHA
formalized its' commitment to address the hazards of silica as outlined in the OR-OSHA Strategic Plan, Goal 2: "Improve workplace safety and health for all workers as evidenced by fewer hazards, reduced exposures and fewer injuries, illnesses and fatalities." OR-OSHA is seeking a 10% reduction, over a five-year period (FY2002-2005), in the hazards associated with silica, primarily through exposure assessment data.
Note: Interested parties are directed to the full text of the Strategic Plan which is available on OR-OSHA's external web page.
In Oregon, the incidence of silicosis since 1977 includes five accepted disabling claims and twelve denied claims, where the nature of injury was primarily silicosis. Other claims, both accepted and denied, included a variety of issues unrelated to the development of silicosis.
There is no substance-specific rule for crystalline silica. Rules related to air contaminants, hazard communication and respiratory protection predominate violations alleged or upheld as compliance issues. Total violations related to
SCOPE: ACTION:
crystalline silica were: FY98 (11); FY99 (8); FY00 (75); FY01 (64). See Appendix D for more information on OR-OSHA rules and their applicability to crystalline silica.
Silicosis is an entirely preventable occupational disease. Symptoms generally take years to develop, usually from prolonged exposure. Shortness of breath is a common symptom, with cough and expectoration development with disease progression, especially among cigarette smokers. Other indications of disease progression include fibrotic nodules and fibrosis of lung tissue, wheezing where chronic obstructive bronchitis or asthma is also present, and cancer. Intense exposures to crystalline silica can result in acute silicosis or accelerated health effects.
Crystalline silica is the basic component of sand, quartz and granite rock. It is used or encountered in a wide variety of industries such as electronics; foundries; manufacture of ceramics, clay and pottery, stone, glass; construction; agriculture; manufacture and use of abrasives; mining and quarrying operations; logging; to name a few.
Appendix A provides a more detailed review of crystalline silica and silicosis.
This directive applies OR-OSHA-wide.
This directive requires that any inspection where the hazards of crystalline silica are addressed through enforcement activities be tracked consistent with OR-OSHA's Strategic Plan. It also places emphasis for inspection on selected SICs.
Inspection scheduling under this directive will incorporate these criteria:
An inspection may be scheduled in nonfixed places of employment when from information available to the Division, recognized health hazards known to be associated with certain processes, are reasonably thought to exist at the place of employment, and the division determines the location of a work-site. (OAR 437-001-0057(7))
Recognized Health Hazard: Crystalline silica is a recognized health hazard. A wide variety of published data support the hazard(s) of crystalline silica, primarily the development of silicosis.
Certain Processes: Workers may be exposed to respirable crystalline silica during activities such as:
demolition of concrete and masonry structures crushing, loading, hauling and dumping of rock chipping, hammering and drilling of rock abrasive blasting using silica sand as an abrasive abrasive blasting of concrete (regardless of abrasive used)
sawing, hammering drilling, grinding and chipping of concrete or masonry
dry sweeping or pressurized air blowing of concrete, rock or sand dust
cutting or sanding on silica containing siding dry sanding on drywall joint compound mixing concrete foundry mold work, knock out and manufacture
Places of Employment: This directive identifies certain SICs where information developed by either federal OSHA or OR-OSHA indicates through inspection activity or sampling data that worker exposure to crystalline silica can be reasonably anticipated.
1622, Bridge, Tunnel & elevated highway construction 1761, Roofing, Siding, and Sheet Metal Work 1799, Special Trade Contractors, NEC 3325, Steel Foundries, Not Elsewhere Classified
SICS may be added or deleted based on additional data; selection of these SICs does not preclude inspection scheduling with other employers outside these SICs. SICs scheduled for inspection include these criteria: (i) those with a minimum of three samples having a severity rating greater than five, i.e., the exposure was at least five times the permissible exposure level for silica; (ii) those with a minimum of two samples having a severity rating greater than ten; and (iii) those with a minimum of one sample with a severity rating greater than twenty-five.
To facilitate programmed planned inspections within these SICs, a master roster of employers will be developed. It will include those employers who have active workers' compensation coverage and have not had a scheduled inspection consistent with OAR 437-001-0057, in the previous 2 years. It will identify those employers with eleven or more employees and those with ten or fewer employees, based on hours worked reported to the Worker's Compensation Division.
An inspection scheduling list will be generated by randomly selecting employers listed alphabetically within a master roster regardless of the selected SICs. Information from phone listings, Construction Contractor Board data, Employment Division, and other sources may be used to determine if the selected employers are engaged in work activities where crystalline silica exposures may be found. The initial inspection scheduling list will consist of 100 employer names sorted by field office. The list will be renewed at least annually or anytime after more than two-thirds of the list has been inspected within the current fiscal year. Inspection history will be updated annually based on the preceding fiscal year.
Joint Safety and Health Inspections - Industrial hygienists conducting construction inspections should consult with safety compliance officers on serious
safety hazards such as falls, electrocution, struck-by, or caught-in hazards. Where resources permit, a joint safety and health inspection should be conducted.
OR-OSHA compliance officers can initiate a programmed planned inspection of operations known to create silica overexposures if there is visible dust and employees are inadequately protected.
APPLICATION:
Inspections under this SEP will address areas of potential crystalline silica dustrelated overexposures where there is an increased risk of silicosis. Inspections will include a review of written documentation, i.e., recordkeeping, air monitoring, medical examinations or evaluations, respiratory protection, engineering and/or work practice controls, hazard communication, material safety data sheets, and training. The compliance officer may expand the
inspection scope beyond crystalline silica-related activities if serious hazards or violations are observed.
Compliance officers must question employers and employees to determine whether the employer has conducted personal or area sampling for dust containing crystalline silica. Where such data has been collected, copies of the data will be obtained consistent with the requirements of ORS 654.101.
Compliance officers must conduct personal employee monitoring and collect bulk samples where appropriate to document exposures unless the compliance officer,
upon review of the employer's silicosis prevention effort, or else the employer has documented, that no overexposure exists.
While evaluating worker exposures to dust containing crystalline silica during abrasive blasting, compliance officers must also be aware of and evaluate potential exposures to noise and metals. Metal exposures often associated with abrasive blasting and other dust creating activities include but are not limited to lead, arsenic, manganese, chromium, cadmium, copper and magnesium.
Compliance officers must follow the sampling and analytical procedures used by the Oregon OSHA Occupational Health Laboratory (OHL). Metals analysis is completed by atomic absorption spectroscopy; however, the analysis for arsenic differs from the other metals, and up to six metals can be requested per sampling filter. Compliance officers need to check with the OHL if different needs are anticipated.
Compliance officers will also interview the employer and employees to determine whether the employer has conducted any medical surveillance of exposed employees. If such surveillance records exist, copies of the records will be obtained where necessary to support a violation. OR-OSHA access to medical records will be conducted consistent with agency policies and procedures. Appendix C contains recommendations for suggestions for a medical monitoring program and should be made available to all employers regardless of the level of exposure to crystalline silica.
If OR-OSHA staff find a product that contains crystalline silica and downstream exposure is reasonably anticipated, e.g., sawing or cutting of brick, tiles and
OUTREACH:
concrete block, they should investigate the adequacy of the material safety data sheets (MSDS) and product labeling. For example, concrete blocks have been found with labels stating "caution, irritant dust," and the MSDS did not address accurately the chronic health hazard.
Worker clothing contaminated with crystalline silica dust can be carried home and potentially expose family members. Work sites where this potential is observed by the compliance officer should be evaluated (including automobiles) and the employer and employee representatives made aware of the hazard of such activity.
Citations and classification of violations for overexposures to crystalline silica dust, respiratory protection, and work practices and/or engineering controls must be issued in accordance with the procedures and requirements of the FIRM.
Managers are encouraged to conduct outreach efforts regarding this SEP in support of the enforcement effort. Contacts may be generated through letters to employers, professional associations, local industrial hygiene organizations, local safety councils, local unions, apprenticeship programs, the Associated General Contractors (AGC), Associated Builders and Contractors (ABC), local hospitals and occupational health clinics, and/or other industry employer organizations that work with or potentially generate crystalline silica dust. Speeches and training sessions provide a means to disseminate information. OR-OSHA encourages the use of its' other resources such as publication information available through the internet ( www.orosha.org ) and related links, the audiovisual lending library, the Resource Center, Joint Emphasis Program (JEP) materials, and Consultative Services.
IMIS CODING: The instructions which follow are for recording silica inspections under this SEP and the strategic plan. The OSHA-1 and AVD must be coded as follows:
Choose Box 25d - National Emphasis Program, "SILICA - Insps - Presence of Silica/Silicates"
Code violations with appropriate silica substance codes:
A514 Aluminum Silicate C112 Calcium Silicate (Total Dust) C122 Calcium Silicate (Resp. Fraction)
S103 Silica (Quartz, non-respirable) S114 Silica, Crystalline Tripoli (as Quartz), Resp. Dust
S122 Silica, Amorphous, Diatomaceous Earth (less than 1% Crystalline Silica)
S245
1230 1777 1778 9010 9013 9015 9017 9050 9075
Sodium Metasilicate
Ethyl Silicate Methyl Silicate Alpha Methyl Silicate Silica, Crystalline Quartz (as Quartz), Resp. Dust Silica, Fused, Resp. Dust Silica, Crystalline Cristobalite, Resp. Dust Silica, Crystalline Tridymite, Resp. Dust Silica, Amorphous, Precipitated and Gel MICA (less than 1% Crystalline Silica)
EFFECTIVE DATE: This directive is effective until cancelled or superceded.
Appendix A
Background: Crystalline Silica and Silicosis
Crystalline silica is a ubiquitous substance which is the basic component of sand, quartz and granite rock. (9) Airborne crystalline silica occurs commonly in both the work and non-work environments. Occupational exposure to crystalline silica dust has long been known to produce silicosis, a pneumoconiosis or dust disease of the lung. Activities such as sandblasting, rock drilling, roof bolting, foundry work, stonecutting, drilling, quarrying, brick/block/concrete cutting, gunite operations, lead-based paint encapsulant applications, and tunneling through the earth's crust can create an airborne silica exposure hazard. In addition some recently noted exposures to crystalline silica include the following:
* Calcined diatomaceous earth can contain anywhere from <1% to 75% cristobalite. In addition to use as a filtering media, calcined diatomaceous earth is often used in industries such as food and beverage preparation where only food grade products and equipment can come in contact with foods or beverages being made.
* Asphalt paving manufacturing may also be a source of crystalline silica exposure, due to the mechanical formation of crystalline silica dust when sand and aggregate passes through rotary dryers. The fine dust can have significant amounts of crystalline silica, depending upon the source of the aggregate. For example, rotary drying of gravel from the Willamette River in Oregon was found to generate dust containing approximately 7 to 12% quartz. The waste dust was transferred periodically by front loader, resulting in clouds of visible dust drifting to the operator.
* The repair or replacement of linings of rotary kilns found in pulp and paper mills and in other manufacturing locations as well as the linings in cupola furnaces are potential sources of crystalline silica exposure. This work may not be commonly seen due to the infrequency and less visible nature of the work location. Turnarounds and yearly shutdowns are the time when this work commonly occurs.
* In food processing operations where crops such as potatoes and beans are readied for market, crystalline silica overexposures have been documented in the sorting, grading and washing areas.
Geologically, quartz is the second most common mineral in the earth's crust. Quartz is readily found in both sedimentary and igneous rocks. Quartz content can vary greatly among different rock types, for example: granite can contain anywhere from 10 to 40 percent quartz; shales have been found to average approximately 22 percent quartz; and sandstones can average almost 70 percent quartz. Silica is a general term for the compound silicon dioxide (SiO2). Silica can be crystalline or amorphous. Different crystalline silica structures exist as polymorphs of silica and include quartz and less common forms such as cristobalite and tridymite. The latter two are less stable than quartz which accounts for the dominance of the quartz form. Quartz can exist as two sub-polymorphs, a-quartz or low quartz, and
B-quartz or high quartz. Of these two forms, a-quartz is more common as the B-quartz is apparently only stable at temperatures above approximately 570 degrees centigrade. Upon cooling, B-quartz
quickly converts to a-quartz. In the literature, crystalline silica is commonly referred to as silica sand, free-silica, quartz, cristobalite, and tripoli. When diatomaceous earth is subjected to pressure or is processed (calcined) at temperatures above 1000 degrees C some of the amorphous silica is converted to crystalline silica in the form of cristobalite.(11) Recent articles have documented the creation of cristobalite in "after-service" refractive ceramic fiber insulation.(12-14) Amorphous silica has been found to exist in nature as opal flint, siliceous glass, diatomaceous earth and vitreous silica.(15)
Silicosis is one of the world's oldest known occupational diseases with reports dating back to ancient Greece. Since the 1800's, the silicotic health problems associated with crystalline silica dust exposure have been referred to under a variety of common names including: consumption, ganister disease, grinders' asthma, grinders' dust consumption, grinders' rot, grit consumption, masons' disease, miner's asthma, miner's phthisis, potters' rot, sewer disease, stonemason's disease, chalicosis, and shistosis. Silicosis was considered the most serious occupational hazard during the 1930's, and was the focus of major federal, state, and professional attention during this time. (10) The hazard is still present 60+ years later. Crystalline silica is commonly found and used in the following industries:
* electronics industry * foundry industries * ceramics, clay and pottery, stone, and glass industries * construction * agriculture * maritime * railroad industry (setting and laying track) * slate and flint quarrying and flint crushing * use and manufacture of abrasives * manufacture of soaps and detergents * mining industries.
Perhaps the most familiar use of quartz sand is as an abrasive blasting agent to remove surface coatings prior to repainting or treating. A recent alert published by the National Institute for Occupational Safety and Health (NIOSH) estimates that there are more than one million American workers that are at risk of developing silicosis. Of these workers, NIOSH further estimates that more than 100,000 are employed as sandblasters. (16) In the United States, from 1968 through 1990 the total number of deaths where silicosis was reported anywhere on the death certificate was 13,744. Of these, approximately 6,322 listed silicosis as the underlying cause of the death. (17) In this study, deaths in the United States due to silicosis were primarily concentrated in 12 states (California, Colorado, Florida, Illinois, Michigan, New Jersey, New York, Ohio, Pennsylvania, Virginia, West Virginia, and Wisconsin.) The silica-related deaths in these 12 states accounted for 68% of the total silica related deaths in the United States. By industry, construction accounted for 10% of the total silicosis-related deaths. (17) Based upon the wide spread occurrence and use of crystalline silica across the major industrial groups (maritime, agriculture, construction, and general industry), and in consideration of the number of silicosis related deaths, the NIOSH estimates for the number of exposed workers, and the health effects of crystalline silica dust exposure (e.g., pulmonary fibrosis, lung and stomach cancer), the Agency is implementing a nationwide special emphasis program to assure worker protection from over exposure to crystalline silica dust.
Health Effects of Silica Exposure
Inhalation of crystalline silica-containing dusts has been associated with silicosis, chronic obstructive pulmonary disease, bronchitis, collagen vascular diseases, chronic granulomatous infections such as
tuberculosis, and lung cancer. In general, aerosols of particulates can be deposited in the lungs. This can produce rapid or slow local tissue damage, eventual disease or physical plugging. Dust containing crystalline silica can cause formation of fibrosis (scar tissue) in the lungs. (9) The inhalation of free crystalline silicon dioxide (SiO2) can produce a fibrotic lung disease known as silicosis. Particle size, dust concentration and duration of dust exposure are important factors in determining the attack rate, latency period, incidence, rate of progression and outcome of disease. A higher attack rate and severity of silicosis are seen with heating crystalline silica-containing materials too greater than 800 degrees C to transform (SiO2) into tridymite and cristobalite (both of which occur naturally and are also found in synthetic silica preparations). High cristobalite concentration also results from direct conversion of diatomaceous earth following heat and/or pressure and can be found in the superficial layers of refractory brick which have been repeatedly subjected to contact with molten metal.(9)
NIOSH has classified three types of silicosis. These include acute, accelerated, and chronic.
Acute Health Effects: Intense crystalline silica exposure has resulted in outbreaks of acute silicosis referred to medically as silico-proteinosis or alveolar lipoproteinosis-like silicosis. Initially, crystalline silica particles produce an alveolitis (inflammation in the gas exchange area of the lung) which is characterized by sustained increases in the total number of alveolar cells, including macrophages, lymphocytes and neutrophils. The alveolitis has been found to progress to the characteristic nodular fibrosis of simple silicosis.
A rapid increase in the rate of synthesis and deposition of lung collagen has also been seen with the inhalation of crystalline silica particles. The collagen formed is unique to silica-induced lung disease and biochemically different from normal lung collagen. (18)
Accelerated Health Effects: Accelerated silicosis may occur with more intense exposure over 5 to 15 years. Fibrotic nodules are generally smaller and the massive fibrosis often occurs in the mid-zones in the lungs.
Acute and accelerated silicosis have been associated with abrasive blasters.
Chronic Health Effects: Chronic silicosis usually takes 20 to 45 years to develop as a result of prolonged exposure to free crystalline silica. Nodular lesions tend to form in the upper lobes. In the simple stage of silicosis, symptoms and impairment of pulmonary function are uncommon. If progressive massive fibrosis (PMF) forms from the coalescence of fibrotic nodules the disease usually progresses, even following removal from exposure. Symptoms of silicosis may not develop for many years. Shortness of breath with exertion is the most common symptom of established silicosis. Cough and expectoration may develop with disease progression, especially in cigarette smokers. Wheezing typically only occurs when conditions such as chronic obstructive bronchitis or asthma are also present. Significant abnormality on a chest x-ray may not be seen until 15 to 20 years of exposure have occurred.
When advanced disease and progressive massive fibrosis are present there is distortion of the normal architecture of the lung. Airway obstruction may occur from contraction of the upper lobes of the lung. Emphysematous changes may develop in the lower lobes of the lung. (19)
Cancer: The issue of crystalline silica exposure and cancer is a complicated one with disagreement in the literature. (20) In worst case, exposure to respirable crystalline silica dust has been associated with lung cancer. (20-26) There also has been the suggestion of stomach cancer associated with ingestion of crystalline silica. (7) The International Agency for Research on Cancer (IARC) in
examining the carcinogenesis of silica has published monographs regarding silica and some silicates. IARC determined that there is sufficient evidence for carcinogenicity in experimental animals with limited evidence for carcinogenicity in humans and has classified silica as a 2B carcinogen. (21) IARC is in the process of revisiting the crystalline silica carcinogen issue based upon recent epidemiological studies.
Studies have demonstrated a statistically significant, dose-related increase in lung cancer in several occupationally exposed groups. Winter (1990) observed that the lung cancer risk for pottery workers increased with estimated cumulative exposure to low levels of silica found in potteries. Another study also found that the risk of lung cancer among pottery workers was related to exposure to silica, although the dose-response gradient was not significant (McLaughlin, et al., 1992). An adjustment for possibly confounding exposure to polycyclic aromatic hydrocarbons slightly raised the odds ratios for exposure to silica. This study also analyzed lung cancer risk in tin miners in China and found a significant trend of increasing risk of lung cancer with increasing cumulative respirable silica exposure. A significant dose-response relationship between death from lung cancer and silica dust particle-years has also been demonstrated for South African gold miners (Hnizdo and Sluis-Cremer, 1991). In this study a synergistic effect on lung cancer risk was found for silica exposure and smoking. Lung cancer risk among workers in the diatomaceous earth industry has been studied by Checkoway, et al. (1993). Results showed increasing risk gradients for lung cancer with cumulative exposure to crystalline silica. The authors felt that this finding indicated a causal relation. Several studies have demonstrated a relationship between the degree of silicosis disability and risk for lung cancer (Goldsmith, 1994). Since severity of silicosis reflects silica exposure, this may also indicate a dose-response relationship for silica exposure and lung cancer (Checkoway, 1993).
For additional information please refer to references No. 22-26.
Note: Due to the potential association between exposure to dust containing crystalline silica and the development of lung and stomach cancer, one may find facilities where the employer is evaluating or has evaluated this exposure using thoracic samplers. Thoracic dust is defined as that portion of inhaled dust that penetrates the larynx and is available for deposition within the airways of the thorax. Thoracic dust includes the respirable fraction. The collection of thoracic dust samples currently is not a method used by OR-OSHA. Field Offices need to be aware that thoracic sampling devices are currently available and one may run across the use of these samplers during inspections. For more information one can consult with the OR-OSHA Occupational Health Laboratory.
Appendix B**
Industries with Potential Overexposure to Crystalline Silica, 1996 to 2001; Federal OSHA Data
SIC CODE Industry Type
1521 1522 1541 1611 1622 1629 1721 1741 1771 1799 3251 3253 3255 3261
3262 3269 3271 3272 3273 3281 3291 3321 3322 3325 3365 3366 3431 3441 3443 3444 3471 3479 3531 3599 3715 3731 3732 7532
General Contractors - Single Family Houses General Contractors - Residential Buildings Other Than Single-Family General Contractors - Industrial Buildings and Warehouses Highway and Street Construction, Except Elevated Highways Bridge, Tunnel and Elevated Highway Construction Highway Construction, NEC Painting and Paper Hanging* Masonry, Stone Setting, and Other Stone Work Concrete Work Special Trade Contractors, NEC Brick and Structural Clay Tile Ceramic Wall and Floor Tile Clay Refractories Vitreous China Plumbing Fixtures and China and Earthenware Fittings and Bathroom Accessories Vitreous China table and Kitchen Articles Pottery Products, NEC Concrete Block and Brick Concrete Blocks, except Block and Brick Ready-Mixed Concrete Cut Stone and Stone Products Abrasive Products Gray and Ductile Iron Foundries Malleable Iron Foundries Steel Foundries, NEC Aluminum Foundries Copper Foundries Enameled Iron and Metal Sanitary Ware Fabricated and Structural Steel* Fabricated Plate Work (Boiler Shops)* Sheet Metal Work* Electroplating, Polishing, and Allied Services, NEC* Coating, Engraving and Allied Services, NEC* Construction Machinery and Equipment* Industrial and Commercial Machinery and Equipment* Truck Trailers* Ship Building and Repairing* Boat Building and Repairing* Top, Body and Upholstery Repair Shops and Paint Shops*
* Crystalline silica exposure primarily from abrasive blasting operations.
Since 1997, from available data, Oregon OSHA has found overexposures in the following SIC codes:
1542
1622 1623 1711 1741 1743 1761 1771 1799 2411 2851 2952 3253 3281 3295 3325 3421 3441 3555 5719 5945
General Contractors-Nonresidential Building, Other Than Industrial Buildings and Warehouses Bridge, Tunnel, and Elevated Highway Construction Water, Sewer, Pipeline, and Communications and Power Line Construction Plumbing, Heating and Air-Conditioning Masonry, Stone Setting, and Other Stone Work
Terrazzo, Tile, Marble, and Mosaic Work Roofing, Siding, and Sheet Metal Work
Concrete Work Special Trade Contractors, Not Elsewhere Classified Logging Paints, Varnishes, Lacquers, Enamels, and Allied Products Asphalt Felts and Coatings Ceramic Wall and Floor Tile Cut Stone and Stone Products Minerals and Earths, Ground or Otherwise Treated Steel Foundries, Not Elsewhere Classified
Cutlery Fabricated Structural Metal Printing Trades Machinery and Equipment Miscellaneous Homefurnishings Stores. Hobby, Toy, and Game Shops
Appendix C
Medical protocol recommendations for exposure to crystalline silica: (28-48)
A. MEDICAL EXAMINATIONS The following are the recommended medical procedures for individuals chronically exposed to crystalline silica or for individuals who have received one or more severe acute exposures to crystalline silica.
1. A baseline examination which includes a medical and occupational history to elicit data on signs and symptoms of respiratory disease prior to exposure to crystalline silica. The medical examination emphasizing the respiratory system, should be repeated every five (5) years if under 20 years of exposure and every two (2) years if over 20 years of exposure. The medical examination should be repeated more frequently if respiratory symptoms develop or upon the recommendation of the examining physician.
2. A baseline chest x-ray should be obtained prior to employment with a follow-up every 5 years if under 20 years of exposure and every 2 years if over 20 years of exposure. A chest x-ray may be required more frequently if determined by the examining physician.
3. Pulmonary Function Tests (PFT): Should include FEV1 (forced expiratory volume in 1 second), FVC (forced vital capacity) and DLCO (diffusion lung capacity). PFTs should be obtained for a baseline examination with PFTs repeated every 5 years if under 20 years of exposure and every 2 years if over 20 years of exposure. PFTs may be required more frequently is respirable symptoms develop or if recommended by the examining physician.
4. A chest x-ray should be obtained on employment termination.
B. MEDICAL MANAGEMENT The chest x-ray should be a chest roentgenogram (posteroanterior 14" x 17" or 14" x 14") classified according to the 1970 ILO International Classification of radiographs of Pneumoconiosis by a certified class "B" reader. The medical follow-up should include the following procedures:
1. With a positive chest x-ray (1/0 or greater) the worker should be placed in mandatory respiratory protection, or if already wearing a respirator, the program should be reevaluated to assure proper fit and that the elements of 29 CFR 1910.134 are being met.
2. The worker should be referred to a physician specializing in lung diseases for a medical evaluation and medical monitoring as warranted by the examining physician. A written opinion from the examining physician as to whether the employee has any detected condition that would place the worker at an increased risk should be provided to the employer and employee, while specific medical findings remain confidential.
3. All medical test results should be discussed with the worker by the physician.
4. In accordance with 29 CFR 1910.1020, medical records shall be maintained for at least 30 years following the employee's termination of employment, unless the employee is employed for less than one year and the records are provided to the employee upon termination.
Appendix D
The standards listed below may be cited for crystalline silica overexposure identified under this SEP, consistent with enforcement policy and procedure:
OR-OSHA Requirement ##
General Industry
Construction
Employer Responsibilities
437-001-0760
Safety Committee
437-001-0765
437-001-0765
Safety & Health Program
none required
1926.20
General Training
1926.21
Recordkeeping (OSHA 300)
OAR 437-001-0700 to 0750 OAR 437-001-0700 to 0750
Abrasive Blasting, breathing air, enclosures, controls
1910.94
1926.28, 55, 95, 100, 101, 102, 103, 300
General PPE
1910.132
1926.28, 95, 100-105
Respiratory Protection
1910.134
1926.103
Hygiene
1910.141
1926.27 and 51
Accident Prevention & Warning Signs
1910.145
1926.200
Permissible Exposure Limits & Controls
OAR 437-002-0382
OAR 437-003-1000
Access to Employee Exposure & Medical Records
1910.1020
1926.33 references 1910.1020
Hazard Communication
1910.1200
1926.59
Note: Such reviews provide an excellent opportunity to address themes consistent with OR-OSHA's Strategic Plan. Employers can use the Safety Committee Self-Evaluation Checklist to determine how well their safety committees are functioning.
Silicosis Prevention Program - The following is a list of elements which may be included in an effective program:
ongoing personal air monitoring program ongoing medical surveillance program training and information to workers on crystalline silica** availability of air and medical surveillance data to workers* an effective respiratory protection program* hygiene facilities and clothing change areas appropriate recordkeeping* personal exposures below the PEL or the facility has an abatement program that also
provides for interim worker protection housekeeping program* in construction: a safety and health program* regulated areas
* Required by specific OR-OSHA standards if an overexposure to crystalline silica exists.
** Hazard Communication training is required if potential exposure exists.
Appendix E
Sample Calculation for a mixture of crystalline silica: (8)
Two consecutive samples from the same employee taken from a combined exposure to crystalline silica dusts have the following results:
Sample
Sampling Period (minutes)
Total Volume (Liters)
Respirable Weight (mg)
Respirable Concentration
(mg/m3)
Laboratory Results (%)
A 238 405 0.855 2.1 5.2 quartz 2.3 cristobalite ND tridymite
B 192 326 0.619 1.9 4.8 quartz 1.7 cristobalite ND tridymite
Totals
430
ND = Non Detected
731
1.474
Calculation of the TWA from the sampling and analytical data:
Step No. 1: Calculate the percentage of quartz, cristobalite, and tridymite in the respirable particulate collected a. Quartz:
Percentage = (weight of quartz in Sample A) + (weight of quartz in sample B) x (100) Total weight of respirable particulate collected
= 0.052(0.855 mg) + 0.048(0.619 mg) x (100) (0.855 mg + 0.619 mg)
b. Cristobalite:
0.044 mg + 0.03 mg x (100) = 0.074 mg x (100) = 0.05(100) = 5%
1.474 mg
1.474 mg
Percentage = (wt. of cristobalite in sample A)+(wt. of Cristobalite in sample b) x (100) Total weight (wt.) of respirable particulate collected
= 0.023(0.855 mg) + 0.017(0.619 mg) x (100) 1.474 mg
= 0.02 mg + 0.011 mg x (100) 1.474 mg
= 0.031 mg x (100) 1.474 mg
c. Tridymite: None Detected = 0%
= 0.021(100) = 2.1% = 2%
Step No. 2 Calculate the PEL for the mixture (use the formula in the OSHA Technical Manual Appendix I-1.5)
PEL(mixture) =10 mg/m3 [ % quartz + 2(% cristobalite] + 2(% tridymite) + 2]
= _____ 10 mg/m3_______ = [5.0 + 2(2.0) + 2(0) + 2]
10 11
= 0/91 mg/m3
Step No. 3 Calculate the employee's exposure to respirable dust
Exposure = (sample weight A + Sample weight B) Total volume of air sampled
= (0.855 mg + 0.619 mg) 731 liters (1 m3/1000 liters)
= 2.0 mg/m3
Step No. 4 Adjust (where necessary) for sampling period less than 8-hours. Assume a zero exposure time for the sampling period remaining.
Adjusted Exposure = (2.0 mg/m(3))(430 minutes) + 0(50 minutes) 480 minutes
= 2.0 mg/m(3) (430 minutes) = 1.8 mg/m(3) 480 minutes
Step No. 5 Calculate the Severity of the exposure:
Severity = Adjusted Exposure PEL(mixture)
= (1.8 mg/m3) (0.91 mg/m3)
=
2.0
If the result from Step 5 is greater than 1.0, then an overexposure to the mixture of crystalline silica exists. Compliance officers must adjust for Standard & Analytical Error (SAE) for citation purposes.
Use of the OR-OSHA OHL's internal web-based "silica calculator" is encouraged.
Appendix F
Checklist for Conducting Silica-Related Inspections
Employee Exposure Monitoring sample for respirable silica leak test filters/cyclones bulk samples of settled dust employer's monitoring records
Engineering and Work Practice Controls location of employees ventilation wet methods
Respiratory Protection written program medical and fit test records cartridge selection and change-out schedule breathing air quality and use
Hazard Communication written program MSDS training bulk samples of products
Symptoms of Silicosis in Workplace survey/interview employees employees obtaining medical evaluations
Medical Surveillance employer awareness of silicosis risk employer identifying possible cases employer referring cases to physician
Housekeeping and Hygiene Facilities facility cleanliness clean-up methods (compressed air, dry sweeping?) change rooms/PPE storage separate break areas
Employee Exposure and Medical Records employer monitoring and medical records employee access and confidentiality
Abrasive Blasting sample for silica and metals sample for noise ventilation and dust control PPE and respirators carbon monoxide alarm on respirator manual control of blast nozzle operating valve electrical grounding
Appendix G: SEP References
References Related to the SEP
1. OSHA Instruction CPL 2.103, September 26, 1994, Field Inspection Reference Manual (FIRM).
2. OSHA Instruction CPL 2.45B, March 3, 1995, The Revised Field Operations Manual (FOM).
3. Rosenman, K.: Use of Hospital Discharge Data in the Surveillance of Occupational Disease. Am. J. Ind. Med. Vol. 13: 281-289 (1988).
4. Lofgren, D.J.: Case Study: Silica Exposure for Concrete Workers and Masons. Appl. Occup. And Environ. Hyg. J. Vol. 8(10): 832- 835 (1993).
5. K. Ringen, et al. Editors. Occupational medicine - Construction Safety and Health State of the Art Reviews. Vol. 10, No. 2 Hanley and Belfus, Inc. April 1995.
6. OSHA Memorandum date August 22, 1994 (Revision September 20, 1995) "Guidance to Compliance Officers for Focused Inspections in the Construction Industry."
7. Lippmann, M.: Exposure Assessment Strategies for Crystalline Silica Health Effects. Appl. Occup. Environ. Hyg. Vol. 10 No. 12: 981-990 (December 1995).
8. Occupational Safety and Health Administration Technical Manual: OSHA Instruction TED 1.15.
References Related to Appendix A
9. Markowitz, G.; Roaner, D.: The Limits of Thresholds: Silica and the Politics of Science, 1935 to 1990. American Journal of Public Health. Vol. 85: 2,254 (1995).
10. Rosner, D.; and Markowitz, G.: Deadly Dust: Silicosis and the Politics of Occupational Disease in Twentieth Century America. Princeton: Princeton University Press, 1991, 1994.
11. Flynn, et al.: Cristobalite Formation in Diatomaceous Earth - Effects of Time and Temperature; Proceedings of the Symposium on Environmental Management for the 1990's. Denver Colorado; Published AIME (Feb. 1991).
12. Ganter, B.A.: Respiratory Hazard from Removal of Ceramic Fiber Insulation from High Temperature Industrial Furnaces. Am. Ind. Hyg. Assoc. J. Vol. 47 (8): 530-534 (1986).
13. Cheng, R.T.; McDermott, H.J.; Gia, G. M.; et al.: Exposure to Refractory Ceramic Fiber in Refineries and Chemical Plants. Appl. Occup. Environ. Hyg. Vol. 7 No. 6: 361-367 (June 1992).
14. Bergen, E.A.v. d.; Rocchi, P. S. J.; and Boogaard, P. J.: Ceramic Fibers and other Respiratory Hazards During the Renewal of the Refractory Lining in a Large Industrial Furnace. Appl. Occup. Environ. Hyg. Vol. 9 No. 1: 32-35 (January 1994).
15. Applied Occupational and Environmental Hygiene Journal. Vol 10, Number 12, pgs. 981 - 1156. (December 1995.) Proceedings of the International Conference on Crystalline Silica Health Effects: Current State of the Art.
16. NIOSH Hazard Alert: Preventing Silicosis and Deaths from Sandblasting.
17. Bang, K. M.; Althouse, R. B.; Kim, J.H.; et al.: Silicosis Mortality Surveillance in the United States, 1968-1990. Appl. Occup. Environ. Hyg. Vol. 10 No. 12: 1070-1074 (1995).
18. Olishifski, L.B.; rev Plog, B.A.: Overview of Industrial Hygiene. Fundamentals of Industrial Hygiene 3rd Ed. Chicago, National Safety Council (1988).
19. Schluter, D.P.: Silicosis and Coal Worker's Pneumoconiosis. Occupational Medicine. Ed Zens C. Et al. 3rd Edition St Louis, Mosby-Year Book, Inc. Pgs 171-173 (1994).
20. Lilis, R.: Silicosis. Maxcy-Rosenau-Last Public Health and Preventative medicine, eds. Last J.M.; et al. East Norwalk, Appleton and Lange pgs. 373-373 (1992).
21. IARC. Silica and Some Silicates, Vol. 42. Lyon. International Agency for Research on Cancer (1987).
22. Checkoway, H.; Heyer, N.J.; Demers, P.A.; et al.: Mortality among workers in the diatomaceous earth industry. Brit. Jour. Ind. Med. Vol. 50: 586-597 (1993).
23. Goldsmith, D.F.: Silica exposure and pulmonary cancer. In: Epidemiology of Lung Cancer, pp. 245-298, Samet, J.M. Ed. New York: Marcel Dekker, Inc. (1994).
24. Hnizdo, E.; and Sluis-Cremer, G.K.: Silica exposure, silicosis, and lung cancer: A mortality study of South African gold miners. Brit. Jour. Ind. Med. Vol. 48: 53-60 (1991).
25. McLaughlin, J.K.; Chen, J.Q.; Dosemeci, M.; et al.: A nested case-control study of silica exposed workers in China. Brit. Jour. Ind. Med. Vol. 49: 167-171 (1992).
26. Winter, P.D.; Gardner, M.J.; Fletcher, A.C.; and Jones, R.D.: A mortality follow-up study of pottery workers: Preliminary findings of lung cancer. In: Occupational Exposure to Silica and Cancer Risk (IARC Scientific Publications, No. 97), pp. 83-94, Simonato, L. Et al.; Eds. Lyon International Agency for Research on Cancer (1990). Reference Related to Appendix B
27. Freeman, C.S.; and Grossman, E.: Silica Exposures in U. S. Workplaces: An Update. In Press. Scand. J. Work and Environ. Health. Vol. 21, Supp. 2: 47-49 (1995).
References Related to Appendix C - Medical
28. ILO (International Labour Office) Committee on Pneumoconiosis. Med Radiogr Photogr. 57(1): 2-17.
29. ATA/CDC (American Thoracic Society and Centers for Disease Control). Treatment of Tuberculosis Infections in Adults and Children. Am. Rev. Respir Dis. Vol. 134(2): 355-363 (1986).
30. Grahm, W.G.B.; O'Grady, R.V.; and Dubuc, B.: Pulmonary Function Loss in Vermont Granite Workers. Am. Rev. Respir. Dis. Vol. 123: 25-28 (1981).
31. Grahm, W.G.B.; Ashikaga, T.; Hememway, D.; et al.: Radiographic Abnormalities in Vermont Granite Workers Exposed to Low levels of Granite Dust. Chest. Vol. 100: 1507-1514 (1991).
32. Grahm, W.G.B.; Weaver, S.; Ashikage, T.; and O'Grady, R.V.: Longitudinal Pulmonary Function Losses in Vermont granite Workers. Chest. Vol. 106: 125-130 (1994).
33. Grahm, W.G.B.: Silicosis. Occupational Lung Diseases. Vol. 13, No. 2: 253-267 (1992).
34. Amandus, H.; Costello, J.: Silicosis and Lung Cancer in U.S. Metal Miners. Arch. Environ Health. Vol. 46: 82-89 (1991).
35. Balmes, J.R.: Medical Surveillance for Pulmonary Endpoints. Occupational Medicine. Vol. 5 No. 3: 499-513 (1990).
36. Batra, P.; and Brown, K.: Radiology in Prevention and Surveillance of Occupational Lung Disease. Occupational Medicine. State of the Art Reviews. Vol. 6, No. 1: 81-100 (1991).
37. CDC. Silicosis: Cluster in Sandblasters - Texas and Occupational Surveillance for Silicosis. MMWR Vol. 39, No. 25: 433-437 (1990).
38. CDC. Silicosis Surveillance - Michigan, New Jersey, Ohio, and Wisconsin 1987-1990. MMWR Vol. 42, No. SS-5: 23-28 (1993).
39. Finkelstein, M.M.: Silicosis Surveillance in Ontario: Detection Rates, Modifying Factors, and Screening Intervals. Amer. J. of Ind. Med. Vol. 25: 257-266 (1994).
40. Froines, J.R.; Wegman, D.H.; and Dellenbaugh, C.A.: An Approach to the Characterization of Silica Exposure in U.S. Industry. Amer. Jour Ind. Med. Vol. 10: 345-361 (1986).
41. Gelb, A.: Physiologic Testing in preventing Occupational Lung Disease. Occup. Med.: State of the Art Reviews. Vol. 6, No. 1: 59-68 (1991).
42. Koskinen, H.: Symptoms and Clinical Findings in Patients with Silicosis. Scand J. Work Environ. health. Vol. 11: 101-106 (1985).
43. Ng, T.; Chan, S.: Quantitative Relations between Silica Exposure and Development of Radiological Small Opacities in granite Workers. Ann. Occup. Hyg.: (suppl 1) 857-863 (1994).
44. Snider, D.E.: The Relationship between Tuberculosis and Silicosis. Am. Rev. Respir. Dis. Vol. 118: 455-460 (1978).
45. Steenland, K.; and Brown, D.: Silicosis Among Gold Miners Exposure - Response Analyses and Risk Assessment. Am. J. Pub. Health.Vol. 85: 1372-1377 (1995).
46. Valiante, D.; Richards, T.; and Kinsley, K.: Silicosis Surveillance in New Jersey: Targeting Workplaces Using Occupational Disease and Exposure Surveillance Data. Amer. Jour. Ind. Med. Vol. 21: 517-526 (1992).
47. Valiante, D.J.; and Rosenman, K.D.: Does Silicosis still occur? JAMA: 3003-3007 (1989).
48. Zisking, M.; Jones, R.n.; and Weill, H.: Silicosis. Am. Rev. Respir. Dis. Vol. 113: 643-665 (1976).
General Silica References
49. Criteria for a Recommended Standard: Occupational Exposure to Crystalline Silica. Washington, D.C. U.S. Department of Health Education and Welfare, Public Health Service, Centers for Disease Control, NIOSH, DHEW (NIOSH) Pub. No. 75-120, (1974).
50. NIOSH. 1992 Alerts. NIOSH publications 92-102 and 92-107. Cincinnati, OH.
51. OSHA Instruction CPL 2-2.38C, October 22, 1990, Inspection Procedures for the Hazard Communication Standard.
52. Corn, J.K.: Historical Aspects of Industrial Hygiene: II. Silicosis. American Industrial Hygiene Journal. Vol. 41(2): 125-133 (1980).
53. OSHA Instruction CPL 2-2.43A; OSHA Chemical Information Manual [also see OSHA Computerized Information System (OCIS) online or the OSHA Compact Disk (CD) for current sampling information. Dated July 1, 1991.
54. Ness, S.A. Air Monitoring for Toxic Exposures. Van Nostrand Reinhold, New York.(1991).
55. Groce, D.W.; Linch, K.D.; Jones, W.G.; and Costello, J.: Silicosis: A Risk in Construction. NIOSH, Div. Of Resp. Disease Studies. Presented at the AIHCE (1993).
56. Linch, K.D.; and Cocalis, J.C.: Commentary: An Emerging Issue - Silicosis Prevention in Construction. John B. Moran, Column Editor. Appl. Occup. Environ. Hyg. J. Vol. 9(8): 539-542 (1994).
57. Hardy, T.S.; Weil, H.: Crystalline Silica: Risks and Policy. Environ. Health Perspec. Vol. 103:152 (1995).
58. OSHA Priority Planning Process, Recommendations for Assistant Secretary Joseph A. Dear and Director Linda Rosenstock, Silica (Crystalline) (July, 1995).
59. Alpaugh, E.L.; rev Hogan, T.J. Particulates Fundamentals of Industrial Hygiene. Ed. Plog, B.A. 34d ed. Chicago, National Safety Council, 141 (1988).
60. Holland, L.M.: Animal Studies of Crystalline Silica: Results and Uncertainties. Appl. Occup. Environ. Hyg. Vol. 10, No. 12: 1099-1103 (1995).
61. Costello, J.; and Grahm, W.G.B.: Vermont Granite Workers' Mortality Study. Amer. Jour. Indust. Medicine. Vol. 13: 483-497 (1988).
62. Memorandum for Regional Administrators from John B. Miles, Jr. Director, Directorate of Compliance Programs. "Hazard Communication Standard: Documentation of Citations Related to the Exposure to Hazardous Substances and Consumer Products." March 21, 1995.
63. Stanbury, M.; Joyce, P.; and Kipen, H.: Silicosis and Workers' Compensation in New Jersey. Jour. Of Occup. And Environ. Med. Vol. 37, No. 12: 1342-1347 (1995).
64. Reilly, M.; Rosenman, K.D.; Watt, F.; et al.: Silicosis Surveillance - Michigan, New Jersey, Ohio, Wisconsin. MMWR. 42/No. SS-5:23-28 (1993).
65. Centers for Disease control and Prevention. Silicosis: Cluster in Sandblasters - Texas, and Occupational Surveillance for Silicosis. MMWR. Morb. Mortal. Weekly Rep. Vol. 39: 433-437 (1990).
66. Rosenman, K.D.; Reilly, M.J.; and Watt, F.C.: 1993 Annual Report on Silicosis in Michigan. Lansing, MI: Michigan Dept. of Health (1993).
67. Nevitt, C.; Saniell, W.; and Rosenstock, L.: Workers Compensation for Nonmaligant Asbestos-Related Lung Disease. Am. J. Ind. Med. Vol. 26: 821-830 (1994).
68. Barth, P.; and Hunt, H.: Workers' Compensation and Work-Related Illnesses and Disease. Cambridge, MA: MIT Press, 1980 256.
69. Rosenman, K.D.; Trimbath, L.; and Stansbury, M.J.: Surveillance of Occupational Lung Disease: Comparison of Hospital Discharge Data to Physician Reporting. Am. J. Public Health. Vol. 80: 1257-1258 (1990).
70. Markowitz, C.; Fischer, E,; Fahs, M.; et al.: Occupational Disease in New York State: A Comprehensive Examination. Am. J. Ind. Med. Vol. 16: 417-435 (1989).
71. Pollack, E.S.; and Keimig, D.G.: Counting Injuries and illnesses in the Workplace: Proposals for a Better System. Prepared by the Panel on Occupational Safety and Health Statistics, Committee on National Statistics, National Research Council, Washington, DC: National Academy press (1987).
72. Windau, J.; Anderson, H.; Rosenman, K.D.; et al.: The Identification of Occupational Lung Disease from Hospital Discharge Data. J. Occup. Med. Vol. 33: 1060-1066 (1991).
73. Slusi, P. Silica Exposures in Construction. Center to Protect Workers Rights. 111 Massachusetts Ave., NW. Suite 509. Washington, D.C. 20001.
73. Robinson, H.; Venable, F.; Stern, C.; et al: Occupational Exposures and the Mortality Patterns of U.S. Construction Trade Workers 1984-1986. Revue d' Epidemiologie et de Sante Publique. Vol. 40 (1992).
