184 CALL 132 100 OR SHOP 24/7 AT RSEA.COM.AU CLICK&COLLECT FREE Pick-up from our Stores ASBESTOS CRYSTALLINE SILICA Asbestos is a material with numerous qualities which was used on a massive scale before being shown to be highly toxic. Prohibited for import and use across Australia since the end of 2003, it can still be found in many buildings and machines. Helping to keep workers in such environments safe, protective coveralls can provide durable, comfortable and robust protection against asbestos fibres. Understanding the Dangers of Asbestos Asbestos is the common name for several naturally occurring fibrous silicate minerals. Asbestos fibres are very heat resistant and strong and were used for many years in thermal insulating materials such as laggings and coatings, floor tiles, roofing, asbestos cement products, electrical insulating materials as well as vehicle clutch and brake linings. Since asbestos is a very friable material, microscopic fibres can release into the air in smaller or larger quantities. Inhalation of asbestos fibres can have serious health effects, including asbestosis, lung cancer and mesothelioma. In Australia, a nationwide ban on importing and using all forms asbestos took effect on 31 December 2003. Reflecting the ban, the National Occupational Health and Safety Commission (NOHSC) revised asbestos-related material to promote a consistent approach to controlling exposure to workplace asbestos and to introduce best- practice health and safety measures for asbestos management, control and removal. The ban did not cover asbestos materials or products already in use at the time the ban was implemented. Although Australia has only a third of the UK’s population, its asbestos disease fatalities approximate Britain’s of more than 3,000 people per year. Minimising the Risk when Working with Asbestos The European Council Directive 83/477/EEC on the protection of workers from the risks related to exposure to asbestos at work and its amendments, deals specifically with protecting workers from the risks related to exposure to asbestos at work. Before any work is done, a comprehensive risk assessment has to be carried out and preventive measures have to be established. Employers have to provide the necessary organisation of work, appropriate equipment (including suitable personal protective equipment), safe systems of work, training, information, and supervision. Suitable personal protective equipment in general includes respiratory equipment, coverall, gloves and safety boots. Choosing Appropriate Protective Clothing Building maintenance and site remediation workers are at a high risk of coming into contact with the fibres when working on insulation in buildings and industrial installations such as pipes, roofs, walls etc. In order to avoid cross contamination, ie: Asbestos fibres attached to a person’s skin or underwear are carried to uncontaminated places, released and then inhaled, protective coveralls must provide a high barrier against airborne particles (Category III EN 13982-1 Type 5 - The Type 5 product standard allows for an inward leakage of up to 15% in 8 out of 10 suits tested). They have to meet the following general requirements: • High particle barrier (material, seams); • Smooth surface to prevent particles from adhering to the garment; • Tight fit at arm and leg openings (elasticated cuffs and ankles); • Compatible with additional PPE (masks, goggles, gloves); and • Comfortable to wear, high freedom of movement. Silica is Silicon Dioxide, which is a naturally occurring mineral that forms the major part of many rocks and soils (granite, shale, sandstone, sand). It’s also used to make concrete, mortar and composite stones. Composite stones are often used to fabricate benchtops for kitchens and bathrooms, as well as other products. When workers fabricate these products (cut, saw, grind, drill, polish, etc.), very small silica dust particles are generated, and become airborne. How Particle Sizes Affect Compliance Efforts One of the more dangerous traits of respirable crystalline silica is the extremely small particle size, which allows them to flow when airborne, and travel on air turbulence (even indoors), for long periods of time. According to the National Institute of Environmental Health Services, the size of dust emissions from silica containing substances varies from 0.01μm (micrometers) to 100μm in diameter. For perspective, the diameter of the average human hair is about 70-100μm. Depending on their weight, dust particles must typically be 200μm or smaller to become airborne and linger, while 50μm and smaller particles are invisible to the naked eye. Particulate matter of ≤10μm (PM10) is the approximate size threshold for particles to be able to penetrate the body’s natural defences (mucus membranes, cilia, etc.) and reach deep into the lungs, potentially causing serious health issues such as silicosis. Managing Risks & Worker Exposures to Silica - Using the Hierarchy of Controls According to the “Model WHS Regulations”, managing risks and worker exposures to silica can be achieved by selecting and implementing measures using hierarchy of controls. More than one control will normally be required to adequately protect workers, and these are as follows; • Substitution such as sourcing composite stone benchtops with a lower percentage of silica • Isolation of the hazard – using principles of safe work design to designate areas for tasks that generate dust and appropriate worker positioning during these tasks, using enclosures and automation to conduct dust generating tasks • Engineering Controls that minimise the risk of exposure to generated dust, for example, local exhaust ventilation, water suppression (wet cutting) or using tools with dust collection attachments • Administrative Controls, including good housekeeping policies, shift rotations and modifying cutting sequences • Personal Protective Equipment including appropriate respiratory equipment and work clothing that does not collect dust. Implementing a strong “Last Line of Defence” at your Work Site – Work Clothing that DOES NOT COLLECT DUST Regulations require that disposable protective coveralls for handling hazardous particles meet the EN 13982-1 Type 5 standard. However, as the Total Inward Leakage (TILA) allowed under this standard is very high (15% in 8 out of 10 suits tested); the more stringent standard of EN 1073-2 Class 2 is desirable, as this requires the Average TILA to be less than 2% for 6 suits tested. Workers using coveralls that meet the EN 13982-1 Type 5 Standard may be unaware that up to 15% of the hazardous fine particles may be entering inside the suit. If appropriate decontamination procedures are not implemented, this can lead to secondary inhalation of silica particles by the worker and family members, if contaminated garments worn under the disposable coveralls are worn home. Material Courtesy of DuPont® Tyvek® Material Courtesy of DuPont® Technical Safety Bulletin. Australian Workplace Exposure Standard for Airborne Contaminants revised December, 2019. WORKING WITH ASBESTOS & CRYSTALLINE SILICA PPE - BODY PROTECTION Silica dust ranges in size and is characterized by its jagged crystalline form. Some of the most harmful airborne particles are too small to see, which complicates silica dust compliance efforts.
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