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| > | Safety Overview | > | HSPP | > | NAIMA's Letter to OSHA |
ATTACHMENT A: THE SYNTHETIC VITREOUS FIBER INDUSTRY’S PRODUCT RESPONSIBLITY PLAN
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INTRODUCTION
In conjunction with NAIMA’s Health and Safety Voluntary Standard, the manufacturers of insulation and special application glass, rock and slag fiber products are implementing a Product Responsibility Plan ("The Plan"). The Plan will commit manufacturers to produce bio-soluble fibers similar to those that have been shown not to produce irreversible effects following inhalation in laboratory animals. Thereby The Plan recognizes that fibers can have different properties. Different fiber formulations are often chosen to impart specific characteristics to the finished product required for its end use. Some characteristics, such as biopersistence or bio-solubility, also may have a role in the potential for the fiber to produce disease in animals. The new scientific data on fiber differentiation has recently prompted the European Union ("EU") to adopt a fiber differentiation system similar to that contained in The Plan.
As set forth below, The Plan establishes several mechanisms whereby a fiber may be deemed a "Plan Fiber" or, in other words, a bio-soluble fiber. In addition, The Plan includes a commitment on the part of manufacturers to formulate or reformulate fibers with an increased bio-solubility when necessary to meet The Plan criteria. The Plan also prescribes specific work practices for those fibers that cannot be classified as Plan Fibers. Special Application fibers that do not meet The Plan criteria are subject to enhanced work practices set forth herein. NAIMA and its member companies will continue to participate in the ongoing discussions and growing understanding of the scientific rationale behind fiber differentiation.
To fully understand the development of bio-solubility as an effective tool in protecting workers, a description of the Industry’s position regarding the safety of its products is provided below.
INDUSTRY’S POSITION WITH REGARD TO SYNTHETIC VITREOUS FIBERS
NAIMA members believe that synthetic vitreous fibers ("SVF") are safe to manufacture, install and use when recommended work practices are followed. SVF have been commercially manufactured and marketed for more than fifty years. During this time, they have become one of the world’s most useful and beneficial man-made materials. The manufacture and use of SVF is an important component of the nation’s economy, providing energy-conserving products that reduce pollution, help conserve the environment through use of recycled materials in its products and promote energy efficiency. Insulation currently in place in residential buildings throughout the United States saves 10.41 quadrillion Btu’s annually. Insulation currently in place in commercial buildings throughout the United States saves 1.51 quadrillion Btu’s annually. Combined, the energy saved by insulation in residential and commercial buildings would generate 41 percent of America’s annual electric consumption.
NAIMA encourages and conducts scientific investigations into the health aspects of SVF products and disseminates the results to government agencies, industry, customers, employers and the general public. SVF health and safety research spans the industry’s history. NAIMA member companies have funded over 50 million dollars of research at leading laboratories and universities in the United States and abroad. In the past ten years, multiple comprehensive reviews of research on the health aspects of SVF by U.S. and international organizations have concluded that SVF have not been shown to cause cancer or nonmalignant respiratory disease ("NMRD") in humans. The industry attaches significant weight to the substantial epidemiology (both mortality and morbidity) which has been conducted for workers in the SVF industry. Over a half century of exposure to tens of thousands of workers, to all fiber compositions, including the most durable compositions, at the highest exposure levels, have not demonstrated a causal association with respect to NMRD, lung cancer, or mesothelioma.
The International Agency for Research on Cancer ("IARC") evaluated animal studies including those in which large amounts of SVF were surgically implanted or injected into the chest and abdominal cavities of laboratory animals. Some SVF artificially inserted in this fashion caused tumors in some of the animals. Based primarily on these studies using non-physiological routes of exposure, IARC considered the data sufficient to justify classifying glass wool and rock and slag wool as 2B substances - "possibly carcinogenic to humans." IARC has two more severe rating categories: "probably carcinogenic to humans" and "carcinogenic to humans."
In 1994, the Department of Health and Human Services ("HHS") included fiber glass (respirable size) in the NTP’s Seventh Annual Report on Carcinogens. The HHS classification essentially follows the IARC assessment and, according to HHS, does not reflect any new scientific information about fiber glass. The Secretary of HHS stated that "the listing of a substance in the Annual Report is descriptive in nature and represents an initial step in hazard identification, which is generally considered the first step in the analytical process known as risk assessment. It is necessary to conduct a risk assessment in order to estimate the potential for any substance to harm human health." The Secretary said, "the listing of a substance in the Annual Report, therefore, does not establish that any such substance presents a risk to persons in their daily lives." The Secretary further clarified the meaning of the NTP listing of fiber glass by explaining that the "entry for glasswool in the Seventh Annual Report characterizes the degree of evidence used to list it as a ‘Reasonably Anticipated’ carcinogen in a manner that corresponds to IARC’s Possible Human Carcinogen category."
In six previous chronic inhalation studies, rats exposed to high doses of a special application glass fiber did not develop tumors or fibrosis. However, in a more recent study, hamsters exposed to this same special application fiber, at Research Consulting Company, developed fibrosis and a single hamster developed mesothelioma six months into the life of the study with no additional mesotheliomas or tumors of any type occurring during the study. Additionally, in another recent study conducted at the Institute of Occupational Medicine ("IOM"), rats exposed to 1000 f/cc of a very fine and more durable glass fiber with low bio-solubility developed fibrosis, lung cancer and mesotheliomas. Animals exposed to a more bio-soluble special application fiber had no significant adverse reactions. The ACGIH and the Commission of the European Communities were provided these findings for their evaluation of SVF (See Note 1.).
The ACGIH recently conducted a comprehensive review of the SVF scientific data. In May 1997, it adopted a classification for glass and mineral wool fibers and special application glass fibers. ACGIH concluded that the available scientific evidence demonstrated that they are carcinogenic in experimental animals at relatively high doses and by routes of administration that are not relevant to worker exposure. ACGIH found that the epidemiological studies did not confirm an increased risk of cancer in exposed humans and that the available evidence suggests that these fibers are not likely to cause cancer in humans except under uncommon or unlikely routes or levels of exposure. As mentioned previously, on the basis of that comprehensive review of all of the science, the ACGIH recommended a 1 f/cc standard for respirable glass wool, special application fibers, and mineral wool fibers.
Based on the extensive, available data, NAIMA remains confident that the weight of scientific evidence demonstrates that SVF are safe to manufacture, install and use when recommended work practices are followed. All interested parties agree that the implementation of more standardized safe work practices and the Product Responsibility Plan throughout the industry will further enhance worker protection. The elements to achieve these objectives are contained in the following Plan.
PRODUCT RESPONSIBILITY PLAN
NAIMA’s manufacturers will implement The Plan in conjunction with its Health and Safety Voluntary Standard. While the Voluntary Standard is designed to manage potential risk by reducing exposure through work practices, PELs, etc., the Product Responsibility Plan is designed to reduce potential risk by encouraging production of bio-soluble fibers similar to those that have been shown not to produce irreversible effects following inhalation in laboratory animals.
The industry has already begun to monitor and in some cases increase the bio-solubility of the Special Application Fibers it produces. Additionally, efforts will be undertaken to identify supplementary means to further reduce potential risk.
Fiber Differentiation - For purposes of The Plan, the Manufacturers differentiate among the various families of SVF on the basis of fiber durability or solubility in the lung. By using dissolution rate constant ("Kdis") as the durability scale, a continuum of fiber solubility (illustrated below) has been adopted by the Manufacturers with the more durable fibers assigned to the lower end of the numerical spectrum and the most soluble fibers at the higher end.
For example, applying Kdis, one of The Plan’s methods of fiber differentiation, SVF may be divided into the following four categories: (i) Kdis 0-10; (ii) Kdis 10-30; (iii) Kdis 30-100; and (iv) Kdis 100 and above. A protocol for measurement of fiber Kdis has been completed.
Fibers with a Kdis of 100 and above are considered "Insulation Plan Fibers;" fibers with a Kdis of 10 - 100 are considered "Special Application Fibers."
EXAMPLE OF FIBER DIFFERENTIATION USING Kdis (See Note 2)
In addition to Kdis, other methods of fiber differentiation such as long term inhalation studies and biopersistence studies are incorporated by the Manufacturers into The Plan Criteria.
The Plan Criteria
Fiber Compositions
Fibers can have different properties. Different fiber formulations are often chosen to impart specific characteristics to the finished product required for its end use. Some characteristics, such as biopersistence or bio-solubility, have a role in the potential for the fiber to produce disease in animals.
The Plan
The Plan is designed to factor bio-solubility into the assessment. Under The Plan, fibers are considered Insulation Plan Fibers if they satisfy one of the following Plan Criteria:
- when tested in an appropriate long term inhalation test with no evidence of significant fibrosis or excess carcinogenicity, or
- when a biopersistence test demonstrates a specified bio-solubility equal to or more soluble than fibers that have shown no evidence of significant irreversible fibrosis or excess carcinogenicity in a long term chronic inhalation study, or
- when a test indicates a specified Kdis range equal to or greater than fibers that have shown no evidence of significant irreversible fibrosis or excess carcinogenicity in a long term chronic inhalation study, or
- when tested by other means that may be developed, accepted and standardized.
All other fibers not satisfying at least one of The Plan Criteria after a period of 3 years will be treated as Special Application Fibers. The protocols for the tests referenced above have been developed.
Manufacturers’ Commitment
As part of The Plan, the Manufacturers commit to formulate or reformulate, where necessary, their insulation fibers not used in special applications, as described above, so that those fibers will be Plan Fibers within three years.
Because of required end use properties, it may not always be possible to make Special Application Fibers more bio-soluble. The Plan will provide an incentive for manufacturers to fully investigate the possibility of changing the composition of Special Application Fibers or to test, in appropriate studies, those fibers that can not be made more bio-soluble. In those instances, where compositional changes are not possible and Special Application Fibers must be produced, where the fiber has not been adequately tested or where it has tested positive, other risk reducing elements of the Voluntary Standard will provide sufficient protection to those working with the product. The Plan will conservatively apply the results of the inhalation studies. In addition, research that will increase the overall knowledge of the potential health effect of SVF will be considered.
Quality Assurance
NAIMA will develop a protocol to assure that fibers meeting The Plan criteria remain at least as bio-soluble as originally tested and will identify independent laboratories capable of conducting quality assurance testing. The protocol will be based upon "in vitro" test methods. Samples will be submitted for quality assurance testing annually or every two years if a satisfactory internal monitoring system to assure compliance is developed. Industry will maintain sampling results for at least five years. If either the quality assurance testing or internal monitoring system indicate that the solubility of the fiber has decreased to below the level of the original test, the manufacturer will immediately take steps to restore solubility and retest the fiber. Test protocols have been developed.
Warning Labels
Recent scientific data and analysis support the discontinuance of a cancer warning label on products containing Plan fibers. The American Conference of Governmental Industrial Hygienists ("ACGIH") recently completed its review of the available scientific data on the health effects of glass, rock and slag wool fibers. After reviewing the data, it concluded that those fibers are not carcinogenic in experimental animals at doses, routes of administration, sites, histological types or mechanisms considered relevant to workers. It found that the extensive epidemiological studies do not confirm an increased risk of cancer in exposed humans. Overall ACGIH determined that the available evidence suggests that these fibers are not likely to cause cancer in humans except under uncommon or unlikely routes or levels of exposure. The European Union also reviewed the carcinogenic potential of these fibers in order to determine whether they required a cancer warning label. In addressing the issue, the EU concluded that there are different bio-solubility characteristics within the fiber family. Based on the differences in bio-solubility, the EU developed a classification and hazard identification system. These and other recent developments have prompted manufacturers to review the continued need for cancer warning labels on products containing Plan fibers.
SPECIAL APPLICATION FIBERS
The work practices and the other components of NAIMA’s Health and Safety Voluntary Standard are applicable to "Special Application Fibers." In addition, the manufacturers of Special Application Fibers adopt the following practices in addition to those found in the Voluntary Standard for the manufacture and fabrication of Special Application Fibers.
Work Practices
Special Application Fiber manufacturers adopt the following work practices for those handling Special Application Fibers ("SAF"):
- SAF are those fibers that do not satisfy The Plan Criteria.
- These work practices are in addition to all other applicable OSHA requirements.
- In accordance with OSHA’s HAZCOM Standard, contractors must give required notices to other workers on the job site regarding the presence of SAF brought onto the job site by the contractor.
- Employees wearing respirators will need to be evaluated annually by a physician to insure the ability of the worker to wear respiratory protection. Follow-up pulmonary function tests and chest X-rays are recommended on a five year basis for all employees.
- It is recommended that workers with potential exposures to SAF at one-half of the voluntary permissible exposure limit also be provided with a pre-employment physical exam, to include a pulmonary function test and chest X-ray, and regular medical surveillance examinations.
- Absence of exposure data in a task or new product will require manufacturers to measure the exposure of their product. In conjunction with industrial hygiene surveys, employee safety training and information regarding the health hazards associated with excessive exposure to respirable fibers will be provided.
- Material safety data sheets will identify these fibers as special application fibers.
- Additional hazard and training materials (e.g., fact sheets, brochures, videos, etc.) will be developed when new published information becomes available.
Worker Training
The members of NAIMA who manufacture or produce Special Application Fibers will provide enhanced health and safety training for production workers, as well as workers involved in the intermediary and end-use of such fibers. Training material and training logs will be made available to OSHA upon request.
Medical Monitoring
NAIMA member companies will maintain a medical monitoring program for their workers involved in the manufacture and production of Special Application Fibers. A protocol for a medical monitoring program has been developed.
Reporting
NAIMA will continue to make reports to OSHA after the implementation of The Plan. Those reports will detail specific activities that have been undertaken by industry to communicate the plan to the scientific community, regulatory agencies, and other stakeholders.
DEFINITIONS
Bio-Soluble Fiber
A bio-soluble fiber is any Synthetic Vitreous Fiber (SVF) which has been tested in a long term chronic inhalation study with no evidence of significant fibrosis or excess carcinogenicity, or which has demonstrated a dissolution rate or a short-term biopersistence which is equivalent to fibers that have shown no evidence of significant irreversible fibrosis or excess carcinogenicity in a long term chronic inhalation study.
Biopersistent Fiber
A biopersistent fiber is any Synthetic Vitreous Fiber (SVF) which has been tested in a long term chronic inhalation study with evidence of significant fibrosis or excess carcinogenicity, or which has demonstrated a prolonged dissolution rate or a short-term biopersistence which is equivalent to fibers that have shown evidence of significant irreversible fibrosis or excess carcinogenicity in a long term chronic inhalation study.
Fiber Glass
A Synthetic Vitreous Fiber (SVF) comprised primarily of boron and silica which is manufactured by air, steam, or flame blowing or via centrifugal forming technique. Principal uses include a wide range of residential, commercial, and industrial insulation as well as acoustical and filtration products.
Glass Wool
A term used to identify fiber glass used in residential, commercial, and industrial insulation and acoustical and filtration products.
Irritation
Irritation is a reaction of the skin, eyes, and/or mucous membranes to mechanical impingement of SVF’s. Reaction is usually transitory, and can be ameliorated by cleansing affected surfaces with warm water. Fiber glass, rock wool, or slag wool products have not been shown to elicit allergic contact dermatitis.
Dissolution Rate Constant (Kdis)
Dissolution rate constant (Kdis) is used to measure the rate of degradation (ng/cm2/hr) of vitreous fibers that is relevant to their likely persistence in the lung. This method scales the degradation process to a single parameter that is a useful approximation to long fiber endurance in the lung.
Mineral Wool
A term used in the United States to collectively refer to rock wool and slag wool fibers.
Respirable Fiber
A respirable fiber is any fiber which is < 3 m in diameter, > 5 m in length, and has an aspect ratio (i.e. length-to-width ratio) equal to or greater than 5:1 as defined by the NIOSH 7400 "B" Method.
Rock Wool
A Synthetic Vitreous Fiber (SVF) comprised mainly of calcium, magnesium, alumina and silica which is manufactured primarily from natural rock such as basalt or diabase using a rotating wheel process. Principal uses include residential, commercial, and industrial insulation.
Slag Wool
A Synthetic Vitreous Fiber (SVF) comprised mainly of calcium, magnesium, silica, aluminum, and other minor elements which is manufactured primarily from iron ore blast furnace slag using a rotating wheel process. Principal uses include residential, commercial, and industrial insulation as well as acoustical ceiling tile and fire proofing.
Synthetic Vitreous Fibers
A Synthetic Vitreous Fiber (SVF) is any fibrous material made from sand, blast furnace slag or rock with a glassy, non-crystalline nature. For purposes of this document, typical SVF’s are fiber glass wool, rock wool, and slag wool.
Thermal and Acoustical Insulation
Thermal and acoustical insulation means a material primarily designed to resist heat flow, which is generally installed between the conditioned volume of a building and adjacent unconditioned volumes or the outside. This term includes but is not limited to insulation products such as batts, blanket, board, spray-in-place, and loose-fill that are used as ceiling, floor, foundation, and wall insulation, and metal building insulation, pipe and boiler insulation, duct liner, duct wrap, and flexible duct medium. It also includes insulation materials used for acoustical purposes within the interior of a building.
Notes |
1The EC has recently undertaken a carcinogenic assessment and classification of insulation wool fibers per its Dangerous Substances Directive (Council Directive 67/548/EEC of June 1967). The EC proposal classifies insulation wool fibers as possibly carcinogenic (Carcinogenic Class. 3). However it proposes that the carcinogenic classification will not apply to SVF that are shown to be sufficiently bio-soluble in the lung. Back |
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2The dotes represent the KDIS of different fibers. Not all fibers currently manufactured are represented on this chart. Back |