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Risk Assessment Asbestos-cement or fiber-cement products (corrugated sheets, culverts, chimney flues), also known by the trade name Eternit, can be hazardous due to the potential release of asbestos fibers normally bound in the cement mortar. These products are known for their resistance to corrosion, high temperatures, and wear, as well as for their light weight. Because of these characteristics, asbestos-cement was widely used in construction from the 1950s through the early 1990s.
The use of asbestos has been prohibited by law in Italy since 1992. Even minimal exposure to asbestos dust can cause asbestosis, a disease that may be accompanied by a specific type of cancer, pleural mesothelioma. The most carcinogenic types of asbestos are the amphiboles, and among these, crocidolite is the most feared. An asbestos fiber is 1,300 times thinner than a human hair. There is no safe threshold below which the concentration of asbestos fibers in the air is not dangerous: theoretically, inhaling even a single fiber can cause mesothelioma; however, prolonged exposure or exposure to high quantities exponentially increases the risk of developing the disease.
It is important to emphasize that the greatest risks of asbestos exposure occur during the handling of products, particularly in cases of breakage, abrasion, or impact that can damage the binder. Asbestos-cement roofing or other products in good condition may remain in place and, only in the event of maintenance or removal, require special precautions to protect the environment and workers.
The actual risk associated with the presence of asbestos depends on the likelihood that it will release fibers into the environment (based on the nature of the material and its condition) and on the likelihood that airborne fibers will be inhaled.
The key tools for risk assessment are:
• Asbestos Risk Assessment—AMLETO Algorithm / Rev. 2019: visual inspection, in accordance with the guidelines set forth in the Resolution of the Region of Tuscany (C.R.) No. 7 of February 14, 2017, of the condition of asbestos-containing materials, in order to estimate the risk of fiber release;
• Tear test: assessment of surface degradation conducted as specified in the UNI 10608:1997 standard and, consequently, of the potential for fiber release into the environment;
• Environmental monitoring: determination of the concentration of airborne asbestos fibers using environmental samplers and fiber counting on the filter.
At the conclusion of the assessment process, it will be possible to determine which remedial measures to adopt. If the materials are intact and in good condition, it will suffice to conduct periodic inspections and implement a maintenance strategy to preserve their good condition over time. If, on the other hand, the materials are found to be in poor condition following the risk assessment, remediation will be necessary.
Remediation
: The term “remediation” does not necessarily mean the removal of the materials; rather, conservative measures—such as encapsulation or containment—can be equally effective. In these cases, the asbestos-containing material remains in place, but the elements contributing to its degradation over time have been eliminated.
Possible remediation techniques include:
• Containment/Recoating: This involves installing a sealed barrier to isolate asbestos-containing materials; it can be applied when the material is in excellent condition and the supporting structure can withstand a new coating.
• Encapsulation: This involves treating asbestos-containing materials with penetrating or coating products that bind and encapsulate the asbestos fibers; it can be used when the material does not have completely deteriorated sections.
• Removal: This involves the removal and disposal of asbestos-containing materials; this solution is necessary for structures in very poor condition.
The most appropriate remediation method should be selected only after a careful risk assessment and based on the best cost-benefit ratio for the specific case. Although encapsulation and containment are less expensive than removal, there are some drawbacks to consider:
• A monitoring and maintenance program is required.
• Subsequent removal will incur higher costs.
• The procedure may need to be repeated over time.
• In the case of roofing, there is a risk of overloading the roof.
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| | Environmental Monitoring and Condition Assessment | |
Quantification of
Airborne Asbestos Fibers• Environmental monitoring: determination of the concentration of airborne asbestos fibers.
Recommended for workplaces or homes where Eternit elements (roofing, chimney flues, boxes, etc.) or other architectural components posing an asbestos risk (e.g., insulation panels, pipes, heating ducts, etc.) are present. | AMLETO Algorithm for Eternit Roofing•
Visual inspection—assessment of the condition of asbestos-containing materials to estimate the risk of fiber release, according to the AMLETO Algorithm - Tuscany Regional Council Resolution No. 7 of February 14, 2017 – BURT No. 9, Part II, of March 1, 2017;
Some of the parameters assessed for the evaluation are:
• identification of the material’s components, including the type of asbestos fibers (chrysotile, crocidolite, amosite, anthophyllite, actinolite, or tremolite);
• age;
• friability of the material;
• condition (evidence of cracks, breaks, or flaking);
• integrity (corrosion exposing asbestos fibers);
• growth of mold and/or lichens on the surface;
• accumulation of powdery material in the eaves or along downspouts;
• presence of aggregated powdery material at drip points;
• proximity to inhabited buildings;
• evaluation of protective surface treatments (painting, encapsulation, etc.). | |
Accreditation by the Ministry of Health
: Laboratories authorized to conduct asbestos risk assessments, determine airborne asbestos fibers, and measure asbestos content in Eternit samples must hold an authorization from the Ministry of Health.
The C.B.A. Chimica Biologia Ambiente analytical laboratory is accredited by the Ministry of Health in accordance with Ministerial Decree 07/07/97. | | | |  |  |  | | |
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