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Management of Asbestos in Vermiculite Insulation

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Management of Asbestos in Vermiculite Insulation Management of Asbestos in Summary Asbestos Fibres Zonolite® - Vermiculite Insulation ‘Vermiculite’ insulation presents a small but identifiable risk to long term health. When it is identified in a building, it should be verified and isolated from the occupied spaces of the building. Personnel required to enter the space containing the vermiculite insulation must wear protective INFORMATION FOR PWS STAFF AND FACILITY USERS clothing and approved respiratory apparatus. For additional Information, contact Technical Support Services, Asset Management Division, Public Works and Services. ASBESTOS Minerals Containing The Issue: Purpose Asbestos Fibres Some vermiculite insulation This document is to inform PWS staff about vermiculite may contain amphibole loose fill thermal insulation and provide operational safety asbestos bres. These guidelines for use when vermiculite is present in a building. products can cause health Loose fill insulation is usually installed in attic spaces above risks if disturbed during ceilings, and occasionally in the sealed compartments What is Vermiculite? maintenance, renovation or between studs in wood frame construction or as fill in cement block construction. Vermiculite was also used in demolition. However, there Vermiculite is a naturally occurring fireproofing materials, and as a lightweight aggregate in is currently no evidence of “mica-like” mineral that was mined construction materials. risk to your health if the and processed into attic insulation insulation is sealed starting in the 1920’s and ending in Vermiculite is a shiny mineral, similar to mica, which pops (encapsulated) behind the early 1990’s. When heated to like corn when heated. The puffy product, as light as cork, wallboards and oorboards, around 1000 degrees C, it pops (or was once a popular form of building insulation and is still an isolated in an attic, or puffs up) which creates pockets of ingredient in potting soil. Vermiculite itself is harmless: The otherwise kept from air. This expanded form, and the Who Do You Contact? problem is that the layers of igneous rock where it is found Further Contacts In Various Areas: exposure to the occupied fact that vermiculite does not burn, may contain asbestos, exposure to which has been areas of a building. made the material suitable for use Your primary contact regarding asbestos in vermiculite • Regional Superintendent (PWS) – Fort Smith Region (867) 872-7401 definitively linked to several fatal lung diseases. Vermiculite as insulation. and vermiculite proucts is the Asbestos Coordinator: • Regional Manager (PWS) – Hay River (867) 874-7002 mined by the W.R. Grace Company at the Libby Montana • Regional Superintendent (PWS) – Inuvik Region (867) 777-7140 mine and marketed under the brand name “Zonolite” has Identifying Asbestos • Regional Superintendent (PWS) – North Slave Region (867) 873-7650 been shown to contain a type of amphibole asbestos fibre, PWS Asbestos Coordinator • Area Manager (PWS) – Fort Simpson (867) 695-7285 commonly called tremolite. Vermiculite from the Libby mine Contaminated Vermiculite: Technical Support Services has not been utilized in Canada since it’s closure in 1990. Asset Management Division, Public Works and Services Asbestos contaminated vermiculite S.M. Hodgson Building, 3rd Floor Not all vermiculite contains asbestos fibres, but the Libby insulation is visually indistinguishable Box 1320, Yellowknife, NT X1A 2L9 mine supplied the majority of the world market in from other uncontaminated brands. Tel: (867) 920-8835 or (867) 920-8088 vermiculite-based insulation until it was closed. This Pieces of vermiculite are silver-gold insulation was sold predominantly under the name Zonolite, to gray-brown and are typically 2mm Fax: (867) 873-0226 but may have been sold under other brand names and may to 10mm long. The pieces look like contain a small percentage of free asbestos fibres they are made of several layers. (especially tremolite). To be safe, if your building has older Reference Sources: vermiculite- based insulation, assume it may contain Loose fill vermiculite insulation some asbestos. containing asbestos can cause http://www.hc-sc.gc.ca/iyh-vsv/prod/insulation-isolant_e.html health risks if disturbed during http://www.ccohs.ca/oshanswers/diseases/vermiculite.html Helping to raise awareness The only way to identify asbestos is through maintenance, renovation or http://www.gov.mb.ca/health/publichealth/cmoh/vermiculite.html of the health risks associated microscopic examination of the material. demolition. However, there is http://www.forces.gc.ca/hr/cfpn/engraph/6_04/6_04_vermiculite-insulation_e.asp currently no evidence of health risk if http://dspinspections.com/vermiculite_insulation.htm with the various forms of vermiculite insulation is sealed http://www.doh.wa.gov/ehp/ts/IAQ/AsbestosVermiculiteInsulation.html asbestos in the North. (enclosed) behind wallboards and http://www.rhdsc.gc.ca/en/lp/lo/ohs/hazard-alerts/vermiculite.shtml Mike Aumond floorboards, isolated in an attic, or http://www.gov.mb.ca/labour/safety/pdf/bulletins/bltn245.pdf Deputy Minister of Public Works and Services otherwise kept from exposure to the occupied portions of a building. TE CHNICAL EX PERTISE NORTH OF 60 ° March 2008 Technical Support Services Department of Public Works and Services VERMICULITE INSULATION What Are The Health Risks How Can The Risk What Do You Do If You Have Been What Are The Methods For Associated With Exposure To Be Minimized? Exposed To Vermiculite Insulation? Identifying, Containing and Isolating Asbestos Contaminated Vermiculite? Vermiculite Insulation? While the actual percentage of asbestos in bulk vermiculite According to the Health Canada advisory “Vermiculite Asbestos related illnesses are usually associated with If you suspect that you have vermiculite insulation in the is very low (typically <1% or trace asbestos), should these Insulation Containing Amphibole Asbestos”, the best way to frequent and prolonged exposure. The time it takes to walls or above the ceiling, as a precautionary step, seal all fibres be disturbed and become airborne, the potential to minimize your risk of asbestos exposure is to avoid develop disease following exposure to asbestos is usually cracks and holes. For example, apply caulking around inhale them is increased, and poses a potential risk to long- disturbing vermiculite insulation. If vermiculite insulation measured in decades. However, there are some steps you window and door frames, along baseboards and around term health. Breathing in very small airborne asbestos is confined and not exposed to the actively used spaces of can take if you may have been exposed. electrical outlets. Collect random samples of the insulation fibres has been associated with respiratory system the building, it poses very little risk. and have it sent to an accredited testing agency for diseases. The potential risk for acquiring the associated • Talk to your health care provider. Currently, there accurate identification and asbestos type verification. PWS diseases will depend on the concentration and size of If you know you have, or believe you may have, vermiculite- are no effective screening methods to determine if currently has a Standing Offer Agreement in place for this asbestos fibres in the air, exposure duration and frequency, based insulation in your building, the following exposure to asbestos has occurred. For those with testing. and the time since the last exposure incident. However, in precautionary steps are recommended: more frequent or prolonged exposure, your health rare cases very minimal exposures to asbestos containing care provider may recommend having a chest X- Samples should be taken from the bottom lower section of the insulation as the asbestos fibres tend to settle out of the material (ACM) have been linked to serious health • Seal all cracks and holes in the ceilings of the ray and may refer you to a specialist. vermiculite particles. Samples should be taken from problems. rooms below the insulation (for example, apply • different areas of the space the vermiculite is contained in. caulking around light fixtures and access hatches Avoid or minimize further exposure to any form of As this product was mainly shipped in bags it is possible Asbestosis is a lung disease that occurs when asbestos with weather stripping seals) to prevent insulation asbestos. This includes making sure future work is that samples from one area can be negative for asbestos fibres are inhaled. It is a chronic disease with slow onset. sifting through. done safely, as well as proper clean up of the area. Asbestosis is characterized by pulmonary fibrosis (the Asbestos awareness training is required if working but samples from different locations could be positive. formation of scar-like tissue). Shortness of breath is the • Restrict access to the space containing the with asbestos when disturbing the material is Samples should also be taken of any dust collecting on most common symptom. In most cases, the first and often insulation and make sure anyone going into the necessary. pipes, ducts or other surfaces in the area. the only physical sign is a crackling sound that can be space knows about the possible presence of • Don’t smoke. Avoid second hand tobacco smoke heard through a stethoscope. Lung function tests and x-ray ‘ACM’. Install warning signs just inside the affected Assistance with this process, which will vary from building and other irritants that could affect your lungs. The diagnosis can help to determine the degree
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