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NSSGA Mineral Identification and Management Guide. Employee Training Module Revision date: June 2011. Introduction. NSSGA supports rigorous regulation to prevent over-exposure to harmful asbestos which has long been regulated as a carcinogen.
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NSSGA Mineral Identification and Management Guide Employee Training Module Revision date: June 2011
Introduction • NSSGA supports rigorous regulation to prevent over-exposure to harmful asbestos which has long been regulated as a carcinogen. • Very often analytical methods that were designed to measure commercial asbestos in built environments are inappropriately applied in natural environments resulting in the misidentification of rock fragments as asbestos.
Introduction • In addition, naturally occurring asbestos may be present in very small concentrations in some of the same rock types as those that are mined for aggregate production across the U.S. • The aggregates industry does not have asbestos-related disease in its workforce and has not been associated with asbestos in its products.
Introduction • In 2009 NSSGA published the Mineral Identification and Management Guide to assess whether protocol mineral fibers are present at aggregates operations. • The purpose of this module is to provide a training template to educate aggregates’ workforces about how to differentiate between naturally occurring asbestos and common rock fragments. The module also provides some background and training on implementation of the Guide.
Overview • Asbestos - definition and characteristics • Rock fragment v. asbestos fiber • Regulations • Health effects of asbestos • Mineral ID & Management Guide
Asbestos defined • Asbestos – commercial term referring to a group of six regulated mineral forms that share a unique set of physical properties
Asbestos defined • Each of the six regulated minerals occurs in both asbestiform and non-asbestiform or prismatic variety. Same chemical composition, but different structure (morphology).
ASBESTOS ROCK Actinolite asbestos Actinolite • Same chemical composition – Ca2(MgFe)5Si8O22(OH)2 • Different physical characteristics caused by geologic conditions – temperature and pressure –RARE • Crushing/processing ROCK will not produce ASBESTOS FIBERS Actinolite asbestos is one of the six regulated asbestos minerals. Non-asbestiform Actinolite is not regulated.
Two forms of the same substance • Same chemical composition – H2O • Different physical characteristics caused by environmental conditions • Crushing ice will not give you snowflakes
Asbestos characteristics • Long, thin, flexible fibers or bundles of fibers… • Parallel fibers with splayed ends “aspect ratio”= length : width
Asbestos characteristics • Other physical properties of asbestos… • high tensile strength • ability to be woven • resistance to chemical and thermal decomposition • high electrical resistance
Asbestos characteristics • “Commercial asbestos” – mined, milled, and processed… Pipe insulation containing chrysotile asbestos
Asbestos or Rock? Asbestos: Long, thin flexible fibers….
Asbestos or Rock? Polarized Light Microscopy Asbestos fibers Non-asbestos cleavage fragments It is critical to use a laboratory familiar with analyzing naturally occurring (v. commercial) asbestos samples.
Asbestos Regulations • OSHA Asbestos Standard • Promulgated 1986-1994 • PEL of 0.1 fiber/cc for six regulated minerals • MSHA Asbestos Standard • Old PEL was 2 fibers/cc • New standard in 2008 • New PEL of 0.1 fiber/cc for six regulated minerals • California has regulations defining “restricted material” as that containing ≥ 0.25% asbestos.
Health Effects of Asbestos • Diseases caused by overexposure to asbestos • Asbestosis • Lung cancer • Mesothelioma • Asbestos related diseases are not present in the aggregates industry.
Non-asbestiform cleavage fragments/ROCKS • No asbestos related disease is associated with exposure to cleavage/rock fragments. • Peer reviewed studies established that asbestosis and mesothelioma are not found in the aggregates industry. All relevant cell toxicology, epidemiological, and animal toxicology studies were evaluated. • Studies were published in Journal of Regulatory Toxicology & Pharmacology, VOL. 52, #1, OCT. 2008, SUPP. #1
Mineral Identification and Management Guide • NSSGA Mineral Identification and Management Guide – August 2009 • The Guide is applicable for any mine site located in areas where igneous or metamorphic rock are mined for aggregate, including sand and gravel pits derived primarily from such igneous and metamorphic parent material.
Mineral Identification and Management Guide • Purpose of the Guide is to determine… • The absence or presence of “protocol mineral fibers” in the deposit. Note: Protocol mineral fibers include the six regulated asbestos minerals, all durable asbestiform amphiboles, and all durable asbestiform zeolites such as erionite and mordenite. • The mineralogy of any asbestiform material • The quantity and distribution of any asbestiform minerals • Based on the findings, what steps, if any, may be appropriate to manage the site and maintain sound working conditions.
Mineral Identification and Management Guide • Step 1 - Periodic on-site geologic inspections • Annually, or at such periods established by a geology professional, inspect each of the mines for the possible presence of “protocol mineral fibers” • Results of the inspection should be documented consistently with other company records andprocedures. • Train employees at site to ID and report suspect material.
Mineral Identification and Management Guide • Step 1. Periodic geologic inspection
Mineral Identification and Management Guide • Step 2 - Program for Testing Settled Dust
Mineral Identification and Management Guide • Step 2 - Program for Testing Settled Dust • Sampling plates or containers are to be located in surge tunnels or locations such that the sample reflects a composite of the complete production of a site. • Samples are collected semi-annually or quarterly depending on the needs of the location. • The sample is analyzed by an approved laboratory for asbestiform minerals. • If asbestiform minerals are identified, further steps should be taken.
Mineral Identification and Management Guide • Step 3 – Qualitative Geologic Survey A Qualitative Geologic Survey should be conductedat a mining site under any of the following conditions: • Protocol mineral fibers are confirmed as a result of on-site inspections by the geology staff; • Protocol mineral fibers are confirmed in the settled dust samples from a site as a result of ongoing Settled Dust Program; • Protocol mineral fibers are confirmed at a site during normal operations, as a result of drilling or other geologic or mining activity; or • A governmental agency determines that protocol mineral fibers may be present at a site.
Mineral Identification and Management Guide • Step 3 – Qualitative Geologic Survey Other reasons to do a qualitative geologic survey include: • Expansion of operations at an existing mining site which is subject to the guide • Development of a greenfield site subject to this guide as a mining site
Mineral Identification and Management Guide Step 3 – Qualitative Geologic Survey The purpose of this survey is to locate and define the source and distribution of the protocol mineral fibers by a detailed field assessment conducted by geology staff (or consultant).
Mineral Identification and Management Guide Step 4 – Further steps If the Qualitative Geologic Survey, in conjunction with a comprehensive mine plan, shows that protocol mineral fibers may occur at a site a plan for future action should be developed.
Mineral Identification and Management Guide • Step 4 – Further steps May include… • modification of the mine plan where protocol mineral fibers occur; • visual identification plan; • increased settled dust sampling; • product sampling.
Mineral Identification and Management Guide NSSGA/MSHA Noise and Dust Workshop • Step 4 – Further steps May include… • implementation of air sampling;
Mineral Identification and Management Guide • Step 4 – Further steps May include… • Training • Employee • Customers • Neighbors • Medical Monitoring • Medical monitoring can be an important part of your employee health and safety program. • Refer to NSSGA Occupational Health Program for more information.
Added Considerations for Use of this Training Module It is important to note that this training is intended for two primary purposes. One is to train interested parties on the NSSGA Mineral Identification & Management Guide including its origins and application. The other is as a template for an employee training module as part of the implementation of the Guide. In both uses, it is critical that this training module be adapted for the specific needs and issues relevant to the company/organization. This should include adding slides, deleting slides and modifying content as appropriate.