ASBESTOS AWARENESS Element 15
I. PURPOSE
To inform the students and workers of the Mining and Mineral Process Engineering Department of the presence of asbestos in their working environment, to recognize the possible health risks, and to ensure that the proper safety precautions have been made. II. DEPARTMENT REQUIREMENTS
The WCB requires the Mining and Mineral Process Engineering Department to follow the Industrial Health and Safety Regulations. III. ACTIONS
Department Head, DSPA. Supervisors, Local Safety Committee Members Provide students and workers with accessible information about asbestos, its harms and occurrence in the work environment. Ensure students and workers are not exposed to a concentration higher than the permissible concentration (the permissible concentration to all types of airborne asbestos is 0.1 fibres/ml for an 8 hour limit (amendment to schedule A of the regulations effective November 1, 1993). This permissible concentration refers to an airborne concentration of asbestos and represents a condition under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse effect.) Ensure that any asbestos waste is transported safely according to the Transport of Dangerous Goods (TDG) Regulations. Ensure in the occurrence of a yearly inspection of the buildings including the asbestoscontaining material. All areas containing asbestos will be identified in a report that can be referred to during the inspection. Damaged materials should be reported to the Asbestos Management Group at 822-8772. Inspections (whether damaged materials were found or not) should also be recorded in the safety committee meeting minutes. Any work performed on known or suspected asbestos-containing materials should be questioned with respect to whether the proper procedures are followed. If there are any doubts or questions, call the Asbestos Management Group at 822-8772. Students and Workers Read the safety manual and be aware of the presence of asbestos and to understand the identification labeling on the doors. Follow the proper procedures when handling asbestos (according to TDG Regulations) Ensure that they themselves are not exposed to concentrations higher than the permissible concentration. INFORMATION ABOUT ASBESTOS, ITS HARMS AND ITS IDENTIFICATION Asbestos, Greek for inextinguishable, is the generic name for a family of six related polysilicate fibrous minerals found naturally. There are two different families: Serpentine: chrysotile (white asbestos) Amphibole: actinolite, amosite (brown asbestos), anthophyllite, crocidolite (blue asbestos), tremolite
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Chrysotile (mined in Canada), amosite and crocidolite asbestos were the most common types of asbestos used in the building industry. Special Properties of Asbestos As a mineral, asbestos has many desirable properties that made it popular as a constituent of building products. Some of the most desirable properties are: i) provides strength in compression and tension, ii) provides insulation and is fire resistant, iii) will not conduct electricity, iv) will not degrade chemically, v) very inexpensive to mine and refine. Common Asbestos Containing Materials Fireproofing or Thermal Spray Rigid Pipe Insulation (Batt or Block) Textiles (Pipe Covering, Felts, Fire Blankets) Cementitious Products (Drain Pipes, Transite Panels) Paper Products (Millboard, Indented, Corrugated High Temp) Typical Uses of Asbestos As asbestos only required minor refining prior to its use in manufacturing, it was a very inexpensive and effective constituent of many products. One of the sectors that utilized asbestos most frequently was the construction industry. Asbestos was added to building materials to give them strength, fire retardancy, color and, in some cases, simply as filler. As a consequence virtually all of the buildings constructed prior to 1980 will contain some form of asbestos building product. The use of asbestos in most products was banned in the early 1970’s but some manufacturers that produce products such as brake linings and clutch facings, have found no other effective replacement for asbestos. Asbestos products fall into two categories: friable: products which contain asbestos, that when dry, can easily be crumbled or powdered by hand. It also means manufactured products that are crumbled and powdered. Examples of friable products are: mechanical insulation, sprayed insulation (fire resistant, acoustic, thermal, condensation control, decorative millboards). non-friable: products where the asbestos is bound in a tight matrix and will not easily shed asbestos fibres under normal day to day use. Examples of non-friable products are: roof shingles, asbestos cement pipes, caulking compounds, floor tiles, paints, joint cements, welding rods. Other products that may fall in either category, depending on their condition, are textiles and papers. Friable sprayed or trowelled asbestos insulating formulations applied for fire protection, thermal or acoustic insulation were used until 1974. Mechanical insulation was applied to pipes, boilers, etc. until the late 1970's. Acoustic or decorative finishes which were sprayed or trowelled in place were also applied until the late 1970's. Building Product Friablity Dates of Use
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1926 - mid 1970’s 1935 – 1974 1950 - mid 1970’s 1950 - late 1970’s 1945 - late 1970’s 1935 – present 1940 – present 1920 - mid 1970’s 1920 - mid 1970’s 1920 - late 1970’s 1950 - 1970’s 1930 – present
Mechanical insulation Spray insulation Texture coat Floor tile Drywall taping compound Cement pipe Brake linings Duct wrap Textiles/gaskets Roofing material Ceiling tiles Cement board
High High moderate – high Low low – moderate low low moderate - high low - moderate low low - moderate low
THE POSSIBLE HEALTH RISKS OF ASBESTOS A) INHALATION EXPOSURE Many factors will determine whether harmful health effects will occur and what type and severity of those health effects will be. Some of these factors include the dose (how much), the duration (how long), durability of the fibre inhaled and the route or the pathway by which you are exposed (breathing, eating, drinking , or skin contact). The primary asbestos-related diseases affecting workers exposed to airborne asbestos fibres are the following: Asbestosis - During the development of asbestosis, asbestos fibres deposited in the terminal bronchioles and alveoli are not cleared as rapidly as in the ciliated portion of the airways. The fibres can stimulate an influx of macrophages which release a variety of inflammatory mediators. The gradual loss of epithelial cells and the deposition of collagen by fibroblasts causes scar tissue to form (fibrosis) in the lungs. The lungs become progressively more rigid as the proportion of scar tissue increases, making it difficult to breathe. The fibrosis, once started, will continue even if exposure to airborne asbestos stops (because asbestos fibres particularly amphiboles are very resistant to breakdown in the lung). A latency period of ten to thirty years may pass before the symptoms of asbestosis become apparent. The primary symptoms are: i) an increase in breathlessness accompanied by sharp pains in the chest ii) increased sputum and coughing follow later in the disease’s progression, iii) in severe cases, impairment of respiratory function may ultimately result in death.
Cancers Lung Cancer - There is little doubt that all types of asbestos can cause lung cancer. As with most carcinogenic agents , there is a substantial latency period (10-30 years) between the
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onset of exposure to asbestos and the occurrence of lung cancer. The chances that asbestos exposure will lead to lung cancer depends not only on the cumulative dose of asbestos, but also on the underlying risk of lung cancer due to other factors (i.e. smoking). 2) Mesothelioma - Mesotheliomas are tumors from the thin membranes that line the body cavity and surround internal organs. Mesotheliomas are relatively rare in the general population, but are often observed in populations of asbestos workers. In contrast to the situation for lung cancer, the effect of asbestos on mesothelioma risk does not appear to be increased by smoking. The risk of mesothelioma from a given level of exposure to asbestos depends primarily upon the time elapsed since exposure (latency), with risk increasing exponentially with time after a lag period of about 10 years. B) INGESTION EXPOSURE An overview of the oral health effects show that ingestion of asbestos causes little or no risk of non-carcinogenic injury. However, there is some evidence that chronic oral exposure may lead to an increased incidence risk of gastrointestinal tumors. ASBESTOS IDENTIFICATION Building Inspection - All buildings under the control of UBC and building prior to 1990 have inspected for asbestos-containing materials. Each room has been entered, suspected materials sampled and the samples analyzed by an independent laboratory. When the materials that contain asbestos have been detected, an assessment of the condition and potential for disturbance was conducted. From these two factors, a level of risk and priority for removal is assigned to each individual material. Asbestos Identification - A coded system identifying asbestos containing materials has been implemented on the UBC Campus. At the access points to each room, one of three identification tags will appear; Figure 1 - This identification sticker is applied to all doors of all rooms that have been inspected by members of the Asbestos Management program. In general, these rooms do not have any suspect asbestos-containing materials or the materials that were suspect, were sampled and found to be non-asbestos. Under normal circumstances, material within the void spaces, if inaccessible, is undetermined. If extensive renovation requires the walls, ceilings or floors be demolished, please contact the Asbestos Management Group for further inspection and sampling. Figure 2 - The use of asbestos-containing drywall taping compound varied in use until the late 1970’s. Most buildings have several generations of renovations with extensive reconstruction of walls and ceilings making quantification of asbestos-containing drywall mud difficult. This being the case, only representative samples of the material have been collected but further sampling in areas scheduled for renovation or demolition is required. In many rooms the only suspect asbestos-containing material is drywall taping compound and these rooms have been labeled with the above sticker. If renovation activities will require the removal of drywall material, contact the Asbestos Management Group to collect samples in the areas affected.
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Figure 3 - As there were many different asbestos building products used throughout the UBC Campus, a coded system had to be developed to identify where the products are located in the rooms. The system is based on the Workplace Hazardous Material Identification System (WHMIS). The stickers are applied to the end of all doors of rooms after they are inspected by the Asbestos Management Group. The numbered code indicates the location and type of asbestos-containing product present in the room. Anyone entering the room will be able, with the keycard (Figure 4 on this page) to decipher where the asbestos products are in the given room. In this case the number 1 indicates there is asbestos material above the ceiling. The number 6, the most common, indicates the flooring material contains asbestos. All Local Safety committees, Campus Planning and Development and trades personnel have been issued keycards to decipher the identification program. Figure 1 Figure 3
Figure 2
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Figure 4
Figure 2
IV. References UBC Abestos Management Group V. Authorities UBC Abestos Management Group
Mining and Mineral Process Engineering Safety Program Manual
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