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Subchapter 7. General Industry Safety Orders
Group 16. Control of Hazardous Substances
Article 110. Regulated Carcinogens
Group 16. Control of Hazardous Substances
Article 110. Regulated Carcinogens
Appendix B to Section 5204 Medical Surveillance Guidelines (Non-mandatory)
Introduction
The purpose of this Appendix is to provide medical information and recommendations to aid physicians and other licensed health care professionals (PLHCPs) regarding compliance with the medical surveillance provisions of the respirable crystalline silica standard (Section 5204). Appendix B is for informational and guidance purposes only and none of the statements in Appendix B should be construed as imposing a mandatory requirement on employers that is not otherwise imposed by the standard. Specific references to section 5204 and its subsection are made throughout the Appendix to help clarify for the PLHCPs and specialists what the regulation requires that can impact an employee's health and exposure to respirable crystalline silica.
Medical screening and surveillance allow for early identification of exposure-related health effects in individual employees and groups of employees, so that actions can be taken to both avoid further exposure and prevent or address adverse health outcomes. Silica-related diseases can be fatal, encompass a variety of target organs, and may have public health consequences when considering the increased risk of a latent tuberculosis (TB) infection becoming active. Thus, medical surveillance of silica-exposed employees requires that PLHCPs have a thorough knowledge of silica-related health effects.
This Appendix is divided into seven sections. Section 1 reviews silica-related diseases, medical responses, and public health responses. Section 2 outlines the components of the medical surveillance program for employees exposed to silica. Section 3 describes the roles and responsibilities of the PLHCP implementing the program and of other medical specialists and public health professionals. Section 4 provides a discussion of considerations, including confidentiality. Section 5 provides a list of additional resources and Section 6 lists references. Section 7 provides sample forms for the written medical report for the employee and the written medical opinion for the employer.
1.1. Overview. The term “silica” refers specifically to the compound silicon dioxide (SiO2). Silica is a major component of sand, rock, and mineral ores. Exposure to fine (respirable size) particles of crystalline forms of silica is associated with severe adverse health effects, such as silicosis, lung cancer, chronic obstructive pulmonary disease (COPD), and activation of latent TB infections. Exposure to respirable crystalline silica can occur in industry settings such as foundries, abrasive blasting operations, paint manufacturing, glass and concrete product manufacturing, brick making, china and pottery manufacturing, manufacturing of plumbing fixtures, and many construction activities including highway repair, masonry, concrete work, rock drilling, and tuck-pointing. New uses of silica continue to emerge. These include countertop manufacturing, finishing, and installation (Kramer et al. 2012; OSHA 2015) and hydraulic fracturing in the oil and gas industry (OSHA 2012).
Silicosis is an irreversible, often disabling, and sometimes fatal fibrotic lung disease. Progression of silicosis can occur despite removal from further exposure. Diagnosis of silicosis requires a history of exposure to silica and radiologic findings characteristic of silica exposure. Three different presentations of silicosis (chronic, accelerated, and acute) have been defined. Accelerated and acute silicosis are less common than chronic silicosis. However, an epidemic of silicosis cases (Hoy et al., 2022, Hua et al., 2023, Fazio et al., 2023) has emerged associated with artificial stone countertop manufacturing and installation, and it is critical to recognize all cases of accelerated and acute silicosis because these are life-threatening illnesses and because they are caused by substantial overexposures to respirable crystalline silica. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies current high exposure and a very marked breakdown in prevention.
In addition to silicosis, employees exposed to respirable crystalline silica, especially those with accelerated or acute silicosis, are at increased risks of contracting active TB and other infections (ATS 1997; Rees and Murray 2007). Exposure to respirable crystalline silica also increases an employee's risk of developing lung cancer, and the higher the cumulative exposure, the higher the risk (Steenland et al. 2001; Steenland and Ward 2014). Symptoms for these diseases and other respirable crystalline silica-related diseases are discussed below.
The respirable crystalline silica particles generated from artificial stone have a more severe toxicologic profile than respirable crystalline silica particles generated from natural stone.
Artificial stone associated silicosis is characterized by a shorter latency, more rapid radiological progression, more accelerated decline in lung function, and higher mortality rate than natural stone associated silicosis (Wu et al, 2020, Rose et al. 2019, Fazio et al. 2023).
The toxicological characteristics of artificial stone include the following:
• High concentration of respirable particles: Cutting artificial stones generates much high concentrations of respirable crystalline silica content (>80%), whereas cutting natural stones produces respirable crystalline silica content of only 4-30% (Carrieri 2020)
• Ultrafine particles: Cutting artificial stone produces high concentrations of ultrafine particles (< 0.1um in diameter), which exhibit very large reactive surface areas and enter the deep lung (Ramkissoon 2022).
• Irregular shapes: Artificial stone particles show more irregular shapes with sharp edges and fractures along the surface compared to natural stone dust particles, which exhibit far fewer surface fractures. (Ramkissoon 2022).
• Sensitizing VOCs: During active cutting, the predominant volatile organic compound (VOC) emitted is styrene, with phthalic anhydride, benzene, ethylbenzene, and toluene also detected. Styrene and phthalic anhydride are asthmagens according to the Association of Occupational and Environmental Clinics. Phthalic anhydride has a Respiratory Sensitization (RSEN) Notation by the ACGIH and has been the most abundant VOC identified, at 26-85% of the total VOC composition of artificial stone emissions Benzaldehyde and styrene were also present in all twelve samples. Styrene is a respiratory irritant. (Ramkissoon 2023).
• Free radicals. Freshly cut RCS dust contains a high concentration of free radicals. A free radical is an atom or molecule containing one or more unpaired electrons in its outer orbit. This makes it unstable, short lived and highly reactive (Pavan 2016).
1.2.1. Symptoms -- shortness of breath and cough, although employees may not notice any symptoms early in the disease. Constitutional symptoms, such as fever, loss of appetite and fatigue, may indicate other diseases associated with silica exposure, such as TB infection or lung cancer. Employees with these symptoms should immediately receive further evaluation and treatment.
1.2.5. Clinical Course-chronic silicosis in most cases is a slowly progressive disease. Under the respirable crystalline silica standard, the PLHCP is to recommend that employees with a 1/0 category X-ray be referred to an American Board Certified Specialist in Pulmonary Disease or Occupational Medicine. The PLHCP and/or Specialist should counsel employees regarding work practices and personal habits that could affect employees' respiratory health.
1.3.1. Symptoms -- shortness of breath, cough, and sometimes sputum production. Employees with exposure to respirable crystalline silica, and especially those with accelerated silicosis, are at high risk for activation of TB infections, atypical mycobacterial infections, and fungal superinfections. Constitutional symptoms, such as fever, weight loss, hemoptysis (coughing up blood), and fatigue may herald one of these infections or the onset of lung cancer.
1.3.5. Clinical Course -- accelerated silicosis has a rapid, severe course. Under the respirable crystalline silica standard, the PLHCP can recommend referral to a Board Certified Specialist in either Pulmonary Disease or Occupational Medicine, as deemed appropriate, and referral to a Specialist is recommended whenever the diagnosis of accelerated silicosis is being considered.
1.4. Acute Silicosis. Acute silicosis is a rare disease caused by inhalation of extremely high levels of respirable crystalline silica particles. The pathology is similar to alveolar proteinosis with lipoproteinaceous material accumulating in the alveoli. Acute silicosis develops rapidly, often, within a few months to less than 2 years of exposure and is almost always fatal. The clinical presentation of acute silicosis is as follows:
1.4.5. Clinical Course -- employees with acute silicosis are at especially high risk of TB activation, nontuberculous mycobacterial infections, and fungal superinfections. Acute silicosis is immediately life-threatening. The employee should be urgently referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation and treatment. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies a profoundly high level of silica exposure and may mean that other employees are currently exposed to dangerous levels of silica.
1.4.6.1. An employee with respirable crystalline silica exposure who has one or more of the following symptoms for 14 or more days unless the symptom is explained by another illness: cough, difficulty breathing, fatigue, shortness of breath, chest pain, weakness, fever, or unexplained weight loss; or
1.5. COPD. COPD, including chronic bronchitis and emphysema, has been documented in silica-exposed employees, including those who do not develop silicosis. Periodic spirometry tests are performed to evaluate each employee for progressive changes consistent with the development of COPD. In addition to evaluating spirometry results of individual employees over time, PLHCPs may want to be aware of general trends in spirometry results for groups of employees from the same workplace to identify possible problems that might exist at that workplace. (See Section 2 of this Appendix on Medical Surveillance for further discussion.) Heart disease may develop secondary to lung diseases such as COPD. A study by Liu et al. 2014 noted a significant exposure-response trend between cumulative silica exposure and heart disease deaths, primarily due to pulmonary heart disease, such as cor pulmonale.
1.6. Renal and Immune System. Silica exposure has been associated with several types of kidney disease, including glomerulonephritis, nephrotic syndrome, and end stage renal disease requiring dialysis. Silica exposure has also been associated with other autoimmune conditions, including progressive systemic sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Studies note an association between employees with silicosis and serologic markers for autoimmune diseases, including antinuclear antibodies, rheumatoid factor, and immune complexes (Jalloul and Banks 2007; Shtraichman et al. 2015).
1.7. TB and Other Infections. Silica-exposed employees with latent TB are 3 to 30 times more likely to develop active pulmonary TB infection (ATS 1997; Rees and Murray 2007). Although respirable crystalline silica exposure does not cause TB infection, individuals with latent TB infection are at increased risk for activation of disease if they have higher levels of respirable crystalline silica exposure, greater profusion of radiographic abnormalities, or a diagnosis of silicosis. Demographic characteristics, such as immigration from some countries, are associated with increased rates of latent TB infection. PLHCPs can review the latest Centers for Disease Control and Prevention (CDC) information on TB incidence rates and high risk populations online (See Section 5 of this Appendix). Additionally, silica-exposed employees are at increased risk for contracting nontuberculous mycobacterial infections and other mycotic infections, including Mycobacterium avium-intracellulare and Mycobacterium kansaii, coccidioidomycosis, and aspergillosis (lossifova et al. 2010).
1.8. Lung Cancer. The National Toxicology Program has listed respirable crystalline silica as a known human carcinogen since 2000 (NTP 2014). The International Agency for Research on Cancer (2012) has also classified silica as Group 1 (carcinogenic to humans). Several studies have indicated that the risk of lung cancer from exposure to respirable crystalline silica and smoking is greater than additive (Brown 2009; Liu et al. 2013). Employees should be counseled on smoking cessation.
PLHCPs who manage silica medical surveillance programs required by section 5204, should have a thorough understanding of the many silica-related diseases and health effects outlined in Section 1 of this Appendix. The employer must make available initial and periodic medical examinations that are required by this standard. At each initial and periodic examination, the PLHCP should consider silica-related health outcomes, with particular vigilance for acute and accelerated silicosis. In this section, the required components of medical surveillance under the respirable crystalline silica standard are reviewed, along with additional guidance and recommendations for PLHCPs performing medical surveillance examinations for silica-exposed employees.
2.1.1. The respirable crystalline silica standard requires the following: A medical and work history that includes past, present, and anticipated exposure to respirable crystalline silica and other agents affecting the respiratory system, including as a result of performing high-exposure trigger tasks; the approximate percentage of time the employee performed high-exposure trigger tasks, if any, over their working lifetime; the type of respiratory protection used by the employee for protection against respirable crystalline silica, if any, over their working lifetime, and the approximate percentage of time the employee used the respiratory protection; current or preexisting respiratory system health conditions or impairment, including signs and symptoms of respiratory disease (e.g., shortness of breath, cough, wheezing); history of TB; and smoking status and history. Taking the time to create a detailed timeline of relevant exposure to respirable crystalline silica, available respiratory protection, and development of other known health conditions is critical to understanding the employee's cumulative impact from current, past and anticipated exposures.
2.1.2.6 The obligation of PLHCPs and specialists to report confirmed silicosis and lung cancer cases to the Division, in accordance with subsection (m)(2), detailed below in Section 3.2.7., in addition to complying with the silicosis reporting requirements under California Code of Regulations (CCR) Title 17, Division 1 State Department of Health Services, Chapter 4 Preventative Medical Service, Subchapter 1 Reportable Diseases and Conditions, sections 2500 et seq., Reportable Noncommunicable Diseases and Conditions § 2800-2812 and § 2593(b).
2.1.3. Additional guidance and recommendations: A history is particularly important both in the initial evaluation and in periodic examinations. A history of and information on past and current medical conditions (particularly a history of kidney disease, cardiac disease, pulmonary disease, connective tissue disease, and other immune diseases), medications, hospitalizations and surgeries may uncover health risks, such as immune suppression, that could put an employee at increased health risk from exposure to silica. This information is important when counseling the employee on risks and safe work practices related to silica exposure.
INITIAL EXAMINATIONS: An initial physical examination, with special emphasis on the respiratory system, for each employee occupationally exposed to high-exposure trigger tasks for at least 30 days each year. This examination shall be made available within 30 days after initial assignment, unless the employee has received a medical examination that meets the requirements of subsection (j)(4) within the last calendar year.
PERIODIC EXAMINATIONS: For each employee covered by subsection (j)(2)(A), a medical examination must be offered once every three years, or more frequently if recommended by the PLHCP, that meets the requirement of subsection (j)(4). For each employee covered by subsection (j)(2)(B), medical examinations meeting the requirements of subsection (j)(4) shall be made available at least every three years, or more frequently if recommended by the PLHCP.
2.2.2. Additional guidance and recommendations: Elements of the physical examination that can assist the PHLCP include: An examination of the cardiac system, an extremity examination (for clubbing, cyanosis, edema, or joint abnormalities), and an examination of other pertinent organ systems identified during the history.
2.3.2.3. The silica standard allows the PLHCP to order additional tests or test at a greater frequency than required by the standard, if deemed appropriate. Therefore, PLHCPs might perform periodic (e.g., annual) TB testing as appropriate, based on employees' risk factors. For example, according to the American Thoracic Society (ATS), the diagnosis of silicosis or exposure to silica for 25 years or more are indications for annual TB testing (ATS 1997). PLHCPs should consult the current CDC guidance on risk factors for TB (See Section 5 of this Appendix).
2.3.2.4. Employees with positive TB tests and those with indeterminate test results should be referred to the appropriate agency or specialist, depending on the test results and clinical picture. Agencies, such as local public health departments, or specialists, such as a pulmonary or infectious disease specialist, may be the appropriate referral. Active TB is a nationally notifiable disease. PLHCPs should be aware of the reporting requirements for their region. All States have TB Control Offices that can be contacted for further information. (See Section 5 of this Appendix for links to CDC's TB resources and State TB Control Offices.)
2.4.1. The respirable crystalline silica standard requires the following: Pulmonary function testing must be performed on the initial examination and every three years thereafter. The required pulmonary function test is spirometry and must include forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and FEV1/FVC ratio. Testing must be administered by a spirometry technician with a current certificate from a National Institute for Occupational Health and Safety (NIOSH)-approved spirometry course.
2.4.2. Additional guidance and recommendations: Spirometry provides information about individual respiratory status and can be used to track an employee's respiratory status over time or as a surveillance tool to follow individual and group respiratory function. For reference, the ATS and the American College of Occupational and Environmental Medicine (ACOEM) recommend use of the third National Health and Nutrition Examination Survey (NHANES III) values, and ATS publishes recommendations for spirometry equipment (Miller et al. 2005; Townsend 2011; Redlich et al. 2014). OSHA's publication 3637, Spirometry Testing in Occupational Health Programs: Best Practices for Healthcare Professionals, provides helpful guidance (See Section 5 of this Appendix). Abnormal spirometry results may warrant further clinical evaluation and possible recommendations for limitations on the employee's exposure to respirable crystalline silica.
2.5.1. The respirable crystalline silica standard requires the following: A single posteroanterior (PA) radiographic projection or radiograph of the chest at full inspiration recorded on either film (no less than 14 x 17 inches and no more than 16 x 17 inches) or digital radiography systems. A chest X-ray must be performed on the initial examination and every three years thereafter. The chest X-ray must be interpreted and classified according to the International Labour Organization (ILO) International Classification of Radiographs of Pneumoconioses by a NIOSH-certified B Reader.
Chest radiography is necessary to diagnose silicosis, monitor the progression of silicosis, and identify associated conditions such as TB. If the B reading indicates small opacities in a profusion of 1/0 or higher, the employee is to receive a recommendation for referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
2.5.2. Additional guidance and recommendations: Medical imaging has largely transitioned from conventional film-based radiography to digital radiography systems. The ILO Guidelines for the Classification of Pneumoconioses has historically provided film-based chest radiography as a referent standard for comparison to individual exams. However, in 2011, the ILO revised the guidelines to include a digital set of referent standards that were derived from the prior film-based standards. To assist in assuring that digitally-acquired radiographs are at least as safe and effective as film radiographs, NIOSH has prepared guidelines, based upon accepted contemporary professional recommendations (See Section 5 of this Appendix). Current research from Laney et al. 2011 and Halldin et al. 2014 validate the use of the ILO digital referent images. Both studies conclude that the results of pneumoconiosis classification using digital references are comparable to film-based ILO classifications. Current ILO guidance on radiography for pneumoconioses and B-reading should be reviewed by the PLHCP periodically, as needed, on the ILO or NIOSH Web sites (See Section 5 of this Appendix).
2.6. A chest computed tomography (CT) scan at the lowest dose possible and any additional recommended testing, shall be included in initial and periodic examinations when deemed appropriate by the PLHCP or specialist. The chest CT can be offered in lieu of the CXR at the discretion of the PLHCP or specialist. It must be included for any employee when deemed appropriate by the PLHCP, for any employee with suspected silicosis or for any employee who has performed, or been exposed to, high-exposure trigger tasks for at least 30 days each year during a total of at least three prior years, regardless of exposure assessment or objective data. There is growing evidence that chest radiography and spirometry are inadequately sensitive for early detection of silicosis. Australian and Italian cases series have documented superior identification of abnormalities consistent with silicosis with the addition of chest computed tomography (CT) (Newbigin et al., 2019; Hoy et al., 2020) and with Chest CT and diffusing capacity of lung for carbon monoxide (DLCO) (Guarnieri et al., 2020), compared to chest radiographs and routine spirometry alone. A recent study has indicated that chest CTs can identify cases of simple silicosis not identified by CXRs evaluated according to the International Labour Organization(ILO) classifications (Hoy et al. 2023) Such findings have prompted the Thoracic Society of Australia and New Zealand to recently recommend the addition of low-dose CT of the Chest and DLCO to screening protocols for countertop fabrication workers (Perret et al., 2020).
2.7. Other Testing. Under the respirable crystalline silica standards, the PLHCP has the option of ordering additional testing they deem appropriate. Additional tests can be ordered on a case-by-case basis depending on individual signs or symptoms and clinical judgment. For example, if an employee reports a history of abnormal kidney function tests, the PLHCP may want to order a baseline renal function test (e.g., serum creatinine and urinalysis). As indicated above, the PLHCP may order annual TB testing for silica-exposed employees who are at high risk of developing active TB infections. Additional tests that PLHCPs may order based on findings of medical examinations include, but are not limited to, chest computerized tomography (CT) scan for silicosis, lung cancer, or COPD, in addition to suspected silicosis, testing for immunologic diseases, and cardiac testing for pulmonary-related heart disease, such as cor pulmonale.
3.1. PLHCP. The PLHCP designation refers to “an individual whose legally permitted scope of practice (i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required” by the respirable crystalline silica standard. The legally permitted scope of practice for the PLHCP is determined by each State. PLHCPs who perform clinical services for a silica medical surveillance program should have a thorough knowledge of respirable crystalline silica-related diseases and symptoms. Suspected cases of silicosis, advanced COPD, or other respiratory conditions causing impairment should be promptly referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
Once the medical surveillance examination is completed, the employer must ensure that the PLHCP explains to the employee the results of the initial and periodic medical examinations and provides the employee with a written medical report within 14 days of the examination. The written medical report must contain a statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment. In addition, the PLHCP's written medical report must include any recommended limitations on the employee's use of respirators, any recommended limitations on the employee's exposure to respirable crystalline silica; including during high-exposure trigger tasks; and a statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational medicine if the chest X-ray is classified as 1/0 or higher by the B Reader, if applicable, or if referral to a Specialist is otherwise deemed appropriate by the PLHCP. The written report must also include a statement describing the findings of a chest CT scan or equivalent and any additional testing, if applicable; and a recommendation on whether a supplied-air respirator is needed for the employee. The report to the employee must also disclose if any determination is made regarding silicosis, suspected silicosis, or lung cancer.
The PLHCP should discuss all findings and test results and any recommendations regarding the employee's health, worksite safety and health practices, and medical referrals for further evaluation, if indicated. In addition, it is suggested that the PLHCP offer to provide the employee with a complete copy of their examination and test results, as some employees may want this information for their own records or to provide to their personal physician or a future PLHCP. Employees are entitled to access their medical records.
Under the respirable crystalline silica standard, the employer must ensure that the PLHCP provides the employer with a written medical opinion within 14 days of each initial and periodic employee examination, and that the employee also gets a copy of the written medical opinion immediately. The PLHCP may choose to directly provide the employee a copy of the written medical opinion. This can be particularly helpful to employees, such as construction employees, who may change employers frequently. The written medical opinion can be used by the employee as proof of up-to-date medical surveillance. The following lists the elements of the written medical report for the employee and written medical opinion for the employer. (Sample forms for the written medical report for the employee and the written medical opinion for the employer, are provided in Section 7 of this Appendix.)
3.1.1.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.1.1.4. A statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational Medicine, where the standard requires or where the PLHCP has determined such a referral is necessary. The standard requires referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for a chest X-ray B reading indicating small opacities in a profusion of 1/0 or higher, or if the PHLCP determines that referral to a Specialist is necessary for other silica-related findings.
3.1.2.6 Note on respirators. When employees perform high-exposure trigger tasks or work within a regulated area where high-risk exposure tasks occur, the regulation specifies the type and conditions under which a powered-air purifying respirator (PAPR). Also specified in the Standard is the use of a supplied-air respirator for any employees known to the employer to be diagnosed with confirmed silicosis, or who meet the definition of suspected silicosis, or whenever the PLHCP or specialist recommends the use of a supplied-air respirator. This specified higher level of protection is critical for minimizing the exposure to hazardous respirable crystalline silica while performing high-exposure trigger tasks and associated work duties. Research on exposures and emissions involving workers exposed to respirable crystalline silica (Cooper at al., 2015; Salamon et al., 2021; Ramkisson et al., 2022), including a “real-world” study on measured exposures amongst engineered stone workers in California (Surasi et al., 2022) support the need for higher levels of respiratory protection for these workers.
3.1.2.8 A statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational Medicine if the chest X-ray provided in accordance with this section is classified as 1/0 or higher by the B Reader, or if referral to a Specialist is otherwise deemed appropriate.
3.1.2.9. In addition to the above referral for abnormal chest X-ray, the PLHCP may refer an employee to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for other findings of concern during the medical surveillance examination if these findings are potentially related to silica exposure.
3.1.2.10. Although the respirable crystalline silica standard requires the employer to ensure that the PLHCP explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the PLHCP has explained the results of the medical examination to the employee.
3.2. Medical Specialists. The silica standard requires that all employees with chest X-ray B readings of 1/0 or higher be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine. Referrals can also be made for other relevant findings or concerns at the discretion of the PLHCP. If the PLHCP's written medical opinion indicates that an employee should be examined by a specialist, the employer shall make available a medical examination by a specialist within 30 days after receiving the PLHCP's written medical opinion.
3.2.1.6. The obligation of PLHCPs and specialist to report (see section 3.2.7. below for details) confirmed silicosis and lung cancer cases to the Division, in accordance with the Standard, in addition to complying with the silicosis reporting requirements under California Code of Regulations (CCR) Title 17, Division 1 State Department of Health Services, Chapter 4 Preventative Medical Service, Subchapter 1 Reportable Diseases and Conditions, sections 2500 et seq., Reportable Noncommunicable Diseases and Conditions § 2800-2812 and § 2593(b).
3.2.3. Once the Board Certified Specialist in Pulmonary Disease or Occupational Medicine has evaluated the employee, the employer must ensure that the Specialist explains to the employee the results of the medical examination and provides the employee with a written medical report within 30 days of the examination. The employer must also ensure that the Specialist provides the employer with a written medical opinion within 30 days of the employee examination. (Sample forms for the written medical report for the employee and the written medical opinion for the employer are provided in Section 7 of this Appendix.)
3.2.4.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.2.5.6. Although the respirable crystalline silica standard requires the employer to ensure that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the Specialist has explained the results of the medical examination to the employee.
3.2.7. After evaluating the employee, the Board Certified Specialist in Pulmonary Disease or Occupational Medicine should provide feedback to the PLHCP as appropriate, depending on the reason for the referral. OSHA believes that because the PLHCP has the primary relationship with the employer and employee, the Specialist may want to communicate his or her findings to the PLHCP and have the PLHCP simply update the original medical report for the employee and medical opinion for the employer. This is permitted under the standard, so long as all requirements and time deadlines are met.
3.2.8. Medical Surveillance Examination Reporting to CDPH. For each silica medical examination conducted, the PLHCP and specialist shall electronically submit to the California Department of Public Health Occupational Health Branch the name and date of the birth of the examined employee, as well as a copy of the PLHCP's written medical report for the employee described in subsection (j)(6). The submission shall be made within 14 days of the medical examination.
Both the employer and the PLHCP have reporting obligations under the respirable crystalline silica standard.
3.2.9.1. Employer responsibilities for reporting. Within 24 hours of receiving information regarding a confirmed silicosis case or lung cancer related to respirable crystalline silica exposure, the employer must report the following information to the California Department of Public Health (CDPH) and to the Division by phone or a specified online mechanism established by these agencies:
3.2.9.2. PLHCP and specialist responsibilities for reporting. Within 24 hours of identifying a confirmed silicosis case, PLHCPs and specialists shall report the case to the Division by phone or a specified online mechanism, in addition to complying with reporting requirements under California Code of Regulations (CCR) Title 17, Division 1 State Department of Health Services, Chapter 4 Preventative Medical Service, Subchapter 1 Reportable Diseases and Conditions, sections 2500 et seq., Reportable Noncommunicable Diseases and Conditions § 2800-2812 and § 2593(b). The report must include the following information:
3.3. Public Health Professionals. PLHCPs might refer employees or consult with public health professionals as a result of silica medical surveillance. For instance, if individual cases of active TB are identified, public health professionals from state or local health departments may assist in diagnosis and treatment of individual cases and may evaluate other potentially affected persons, including coworkers. Because silica-exposed employees are at increased risk of progression from latent to active TB, treatment of latent infection is recommended. The diagnosis of active TB, acute or accelerated silicosis, or other silica-related diseases and infections should serve as sentinel events suggesting high levels of exposure to silica and may require consultation with the appropriate public health agencies to investigate potentially similarly exposed coworkers to assess for disease clusters. These agencies include local or state health departments or OSHA. In addition, NIOSH can provide assistance upon request through their Health Hazard Evaluation program. (See Section 5 of this Appendix)
If a worker has suspected or confirmed silicosis or needs to restrict exposure to respirable crystalline silica for other related concerns, the PLHCP, alone or in consultation with the Specialist, should determine if the worker can safely remain in the workplace. If conditions are unsafe, the worker should be effectively and immediately removed from further exposure to respirable crystalline silica. This work status change may be initiated when the worker begins further evaluation and before a full characterization of the worker's medical condition. The employer should be advised that respirator use, even in the case of supplied-air respirator use, in an exposed environment is not equivalent to removal from exposure. Finally, caution should be exercised when considering returning a worker to usual work tasks even if the health condition has improved and engineering controls have been implemented.
4.1 When the PLHCP determines that an employee needs to be removed from a job assignment or that the employee's job needs to be modified to reduce exposure to respirable crystalline silica, the employer must modify the employee's job or transfer the employee to comparable work for which the employee is qualified, or for which the employee can be trained within a period of six months.
4.2 The employer must maintain the employee's current earnings, seniority, and other benefits for up to six months. If there is no work available that meets the PLHCP's recommended restrictions, the employer must maintain the employee's current earnings, seniority, and other benefits until any of the following occurs:
4.3 Workers' Compensation Claims. If a removed employee files a claim for workers' compensation for a silica-related disability, the employer must provide medical removal benefits to the employee at the employee's normal hourly wage and weekly work schedule for a period of up to six months, pending final disposition of the claim.
4.4.1 After any medical evaluation or consultation conducted as outlined in subsections (j) or (k), the employee may designate an independent PLHCP to review any findings, determinations, or recommendations and to conduct such examinations, consultations, and laboratory tests as this second PLHCP deems necessary and appropriate to facilitate this review.
The information that is provided from the PLHCP to the employee and employer under the medical surveillance section of OSHA's respirable crystalline silica standard differs from that of medical surveillance requirements in previous OSHA standards. The standard requires two separate written communications, a written medical report for the employee and a written medical opinion for the employer. The confidentiality requirements for the written medical opinion are more stringent than in past standards. For example, the information the PLHCP can (and must) include in his or her written medical opinion for the employer is limited to: The date of the examination, a statement that the examination has met the requirements of this section, and any recommended limitations on the employee's use of respirators. If the employee provides written authorization for the disclosure of any limitations on the employee's exposure to respirable crystalline silica, then the PLHCP can (and must) include that information in the written medical opinion for the employer as well. Likewise, with the employee's written authorization, the PLHCP can (and must) disclose the PLHCP's referral recommendation (if any) as part of the written medical opinion for the employer. However, the opinion to the employer must not include information regarding recommended limitations on the employee's exposure to respirable crystalline silica or any referral recommendations without the employee's written authorization.
The standard also places limitations on the information that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine can provide to the employer without the employee's written authorization. The Specialist's written medical opinion for the employer, like the PLHCP's opinion, is limited to (and must contain): The date of the examination and any recommended limitations on the employee's use of respirators. If the employee provides written authorization, the written medical opinion can (and must) also contain any limitations on the employee's exposure to respirable crystalline silica.
The PLHCP should discuss the implication of signing or not signing the authorization with the employee (in a manner and language that he or she understands) so that the employee can make an informed decision regarding the written authorization and its consequences. The discussion should include the risk of ongoing silica exposure, personal risk factors, risk of disease progression, and possible health and economic consequences. For instance, written authorization is required for a PLHCP to advise an employer that an employee should be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation of an abnormal chest X-ray (B-reading 1/0 or greater). If an employee does not sign an authorization, then the employer will not know and cannot facilitate the referral to a Specialist and is not required to pay for the Specialist's examination. In the rare case where an employee is diagnosed with acute or accelerated silicosis, co-workers are likely to be at significant risk of developing those diseases as a result of inadequate controls in the workplace. In this case, the PLHCP and/or Specialist should explain this concern to the affected employee and make a determined effort to obtain written authorization from the employee so that the PLHCP and/or Specialist can contact the employer.
Finally, without written authorization from the employee, the PLHCP and/or Board Certified Specialist in Pulmonary Disease or Occupational Medicine cannot provide feedback to an employer regarding control of workplace silica exposure, at least in relation to an individual employee. However, the regulation does not prohibit a PLHCP and/or Specialist from providing an employer with general recommendations regarding exposure controls and prevention programs in relation to silica exposure and silica-related illnesses, based on the information that the PLHCP receives from the employer such as employees' duties and exposure levels. Recommendations may include increased frequency of medical surveillance examinations, additional medical surveillance components, engineering and work practice controls, exposure monitoring and personal protective equipment. For instance, more frequent medical surveillance examinations may be a recommendation to employers for employees who do abrasive blasting with silica because of the high exposures associated with that operation.
ACOEM's Code of Ethics and discussion is a good resource to guide PLHCPs regarding the issues discussed in this section (See Section 5 of this Appendix).
ACOEM Code of Ethics. Accessed at: http://www.acoem.org/codeofconduct.aspx
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Contacting OSHA: http://www.osha.gov/html/Feed_Back.html
OSHA's Clinicians Web page. (OSHA resources, regulations and links to help clinicians navigate OSHA's Web site and aid clinicians in caring for workers.) Accessed at: http://www.osha.gov/dts/oom/clinicians/index.html
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Three sample forms are provided. The first is a sample written medical report for the employee. The second is a sample written medical opinion for the employer. And the third is a sample written authorization form that employees sign to clarify what information the employee is authorizing to be released to the employer.
)
)
Credits
Note: Authority cited: Sections 142.3, 9020, 9030 and 9040, Labor Code. Reference: Sections 142.3, 9004(d), 9009, 9020, 9031 and 9040, Labor Code.
History
1. New Appendix B filed 10-17-2016; operative 10-17-2016 pursuant to Labor Code section 142.3. Submitted to OAL for filing and printing only pursuant to Labor Code section 142.3(a)(3) (Register 2016, No. 43).
2. Editorial correction of paragraph 2.3.2.2. (Register 2016, No. 46).
3. Amendment filed 2-5-2025; operative 2-5-2025 pursuant to Government Code section 11343.4(b)(3) (Register 2025, No. 6).
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