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Encasement is the coating over, covering or "encasing" of all building components, interior and exterior. This includes all roofing and toxic hazards materials, such as asbestos, lead-based paint, mold/mildew and other harmful substances, found in buildings. The technique of encasing all building components, including unsafe ones, with green coatings is by far the most efficient way to reduce the harmful effects on people and the environment while lengthening the life of buildings. It is an economical alternative to other abatement methods such as removal, disposal and replacement. Encasement with green coatings is a long-term, sustainable, and renewable solution compared to typical paints or coatings which only last a few years. In place management and restoration with encasement green coatings is the best and most practical way to extend a buildings life along with safely dealing with most of its components. Encasement is also less disruptive of ongoing services. It does not require shutting down buildings or having to relocate occupants, which is costly and time consuming. Most work can be completed with minimal amount of time and with no building disruption at all. Encasement with green coatings can result in savings of 25% to 75% over removal and replacement, and extend the life of most building surfaces. Green coatings have no environmental downside to using them. They are non-toxic, water based, low VOCs, (Volatile Organic Compounds), no ODS (Ozone Depleting Substances), and Class A fire rated. The products are backed up with toxicological reports proving that they are so clean, that pregnant women and children can be present when applying them. Green coatings used for encasement should be extremely durable, long lasting and able to take a lot of abuse. They must be especially flexible; being able to elongate with the expanding and contracting of any typical building movements. ==Abatement methods== Since the early 1980s, four major methods have been used for the abatement of Asbestos-Containing Materials (ACM) and Lead-Based Paint (LBP). Enclosures – Dust-tight barriers such as sheetrock or plywood are erected to protect against the release of the hazardous material into the environment. When the enclosure is eventually removed, the hazardous material is once again exposed and it usually has become more friable and prone to being released into the atmosphere. Care must be taken to insure that untrained or uninformed workers do not re-expose the hazardous surfaces unknowingly and endanger themselves and/or the inhabitants by causing a release into the environment.〔http://www.epa.gov/asbestos/pubs/ashome.html#manage〕 Encapsulation – A coating material that passes U.S. Environmental Protection Agency-specified (EPA) ASTM (American Society for Testing Materials) tests is applied over a surface to prevent the release of hazardous materials into the atmosphere. A problem experienced with encapsulants in some cases is that the added weight of the encapsulant can cause ACM fireproofing on ceilings or walls to delaminate. A second potential problem with encapsulants is that if the coating is compromised (e.g. by a forklift truck running into a column that has been encapsulated, the potential for release of the hazardous material into the environment is once again present. With LBP, a significant amount of scraping of loose, flaking paint is often required to provide a stable surface before the encapsulant that is applied can be expected to achieve adequate adhesion.〔 Encasement – A 2-coat system which also passes EPA-specified ASTM testing wherein the first coat (primer) stabilizes the substrate by penetrating into the friable ACM and through the loose flaking paint and cures into a flexible film that mitigates these hazardous properties. The second coat bonds to the topcoat providing a tough, long-lasting, monolithic, composite coating system that prevents the release of any hazardous material into the environment. Because of the penetration of the primer, the adhesion of the overall system is increased. A necessity as the weight of the system increases. Additionally if the outer coat is compromised in any manner, there is little or no risk of the hazardous material being released because the surface-stabilizing primer has mitigated the brittle, chalky and friable properties of the hazardous surface. In a very real sense, encasement can be viewed as "stabilization + encapsulation". Removal and Replacement- removal of ACM or LBP causes the release of asbestos fibers and lead dust that can become airborne subjecting installers and/or occupants to the risk of inhaling the particulate matter. Based on industry trends, the increased risk associated with this method has led building owners and contractors to select this as the least preferred method and a last resort unless the ACM is in a friable condition. Due to its high cost and risk factors, only certified and insured abatement professionals should perform this method. If a party is exposed to these risks and are affected, symptoms of various diseases such as asbestosis, a scarring of lung tissue that leads to difficulty in breathing and mesothelioma (an always fatal cancer of the lung’s external lining) may not appear for 15 years. In addition, removal and replacement is time consuming, carries high insurance costs, causes building use downtime and requires relocation of occupants. It also requires the disposal of the hazardous materials, which alone can amount to 30% of total abatement costs. Consequently, an ever-increasing number of building owners choose alternative in place management methods. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Encasement」の詳細全文を読む スポンサード リンク
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