What is asbestos?
Asbestos is a term used to describe a group of asbestiform (fibrous) silicate minerals. These minerals are classified into two families:
- Serpentine members are characterized by their curved fibers.
- Chrysotile is the only member.
- Amphibole members are characterized by their needle-like fibers
- Amosite, Crocidolite, Actinolite, Tremolite and Anthophyllite.
Historically, chrysotile has accounted for over 90% of the world’s asbestos production.
The physical properties of asbestos – durability, flexibility, high tensile strength and resistance to heat, chemicals and electricity, made it suitable for a number of commercial applications including textiles, cement pipe, brake pads, gaskets, roofing material, caulking, floor tiles, insulation and fireproofing material i.
Until the late 1970’s, asbestos was used in the manufacture of low density and friable (easily crumbled by hand pressure) products such as heat and acoustic insulation. The practice of applying sprayed-on asbestos insulation was voluntarily stopped by industry in 1973 and later prohibited by Canada under the Hazardous Products Act due to the difficulty in controlling exposure when using such products.
Today, chrysotile is still mined globally in reduced quantities and is used in the manufacture of asbestos-cement water & sewer pipes, corrugated roofing shingles, brake & clutch friction products and textiles ii.
Asbestos-related health hazards
When left intact and undisturbed, asbestos materials generally do not pose a health risk. However, asbestos materials can become hazardous when, due to damage or deterioration over time, they release fibers into the air iii.
If these fibers are inhaled in significant quantities, they can cause a number of serious respiratory diseases including asbestosis and mesothelioma. The effects of exposure are dependent upon the size of the fibers, the concentration of fibers in the air, the length of exposure, the frequency of exposure and the time lapse since initial exposure iv.
This topic is explored in more detail in the Asbestos Awareness Online Training.
Asbestos Exposure
Asbestos exposure may occur by inhalation of airborne fibers or ingestion of water borne fibers. These fibers originate from naturally occurring sources of asbestiform minerals or from the erosion or disturbance of manufactured products such as automotive brakes & clutches, insulation, roof singles and cement.
Low levels of “background” asbestos are almost always present in the air. The amount of background asbestos depends on a variety of factors, such as: living in an urban vs rural area, proximity to mines or factories, and disturbance of asbestos-containing materials in your environment
For example, 10 fibers are typically present in a cubic meter of outdoor air in rural areas, approximately the amount of air that a human will breathe in one hour. This represents a concentration of 0.00001 fibers/milliliter (0.00001 f/ml). Fiber concentrations in urban areas are typically 10 times higher at 0.0001 f/ml, while fiber levels may reach 0.01 f/ml or higher near asbestos factories or mines. Indoors, the concentration of airborne asbestos depends upon whether building materials such as insulation or ceiling tiles contain asbestos and whether these materials are in good condition. Fiber concentrations in homes, schools and other buildings that contain asbestos typically range from 0.00003 to 0.006 f/ml.
People who work with asbestos-containing materials such as miners, insulation workers, abatement workers or automobile brake mechanics, may potentially be exposed to much higher levels of airborne fibers. Maintenance and custodial workers who perform repair or installation work in buildings with asbestos-containing materials may also be exposed to higher levels of airborne fibers v. Currently in Ontario, the maximum permissible level of airborne fibers is 0.01 f/cc (cubic centimeter) which is equivalent to 0.01 f/ml vi.
Asbestos Awareness Training
An online training course has been developed to allow students, staff and faculty the opportunity to increase their knowledge and understanding of asbestos. Specifically, the awareness training will cover the following topics:
- Historical background of asbestos use
- asbestos-related health hazards
- regulatory (legal) framework
- asbestos management at Carleton
For more information, visit the Asbestos Awareness Online Training page.
Asbestos Management at Carleton
Carleton University has developed an Asbestos Management Policy to protect students, faculty, staff, contractors and visitors from exposure to harmful levels of asbestos fibers.
The Carleton Asbestos Management Program has been developed to prevent exposure to harmful levels of asbestos fibers associated with the uncontrolled or unintentional disturbance of asbestos-containing materials in University-owned buildings.
This program addresses access to areas which may house asbestos-containing materials as well as all maintenance, repair, alteration and installation activities which may disturb such materials. In addition, the Asbestos Management Program ensures compliance with Ontario Regulation 278/05 “Designated Substance – Asbestos on Construction Projects and in Buildings and Repair Operations” and Ontario Regulation 279/05 “Designated Substance – Asbestos”.
The Asbestos Management Program has been created to document and communicate the procedures to minimize potential exposure to asbestos-containing materials. The program aims to:
- provide a safe and healthy campus environment;
- prevent exposure to harmful levels of asbestos fibers associated with the uncontrolled or unintentional disturbance of asbestos-containing materials;
- and comply with regulatory requirements.
The Asbestos Management Program is administered by the office of Environmental Health & Safety, and the Assistant Vice-President (Facilities Management and Planning).
Questions or concerns about asbestos at Carleton University should be directed to Zaneta Polis, Manager of Environmental Health and Safety Safety.
Carleton Inventory of Asbestos-Containing Materials
A campus-wide asbestos survey has been performed by evaluation materials room-by-room and submitting samples of suspected materials for laboratory analysis. The sampling procedure is strictly enforced to prevent accidental release of asbestos fibers. Materials confirmed to be asbestos-containing are added to the Asbestos-Containing Materials Inventory along with:
- the exact location of the material;
- the type and concentration of asbestos present;
- the material’s friability;
- the material’s overall condition;
- and a photo of the material for easy identification.
The purpose of this survey is to inform building occupants as well as Facilities Management & Planning (FMP) staff of the location of asbestos-containing materials and to prevent the accidental disturbance of these materials. Detailed information and training is provided to FMP workers who are likely to disturb asbestos-containing materials over the course of their work.
A summary of Carleton buildings containing asbestos is available for the general Carleton community.
References
i Van Gosen, Bradley S., 2005, “Reported Historic Asbestos Mines, Historic Asbestos Prospects and Natural Asbestos Occurrences in the Eastern United States” , U.S. Geological Survey Open-File Report 2005 – 1189, Version 2.0, p. 1, 2
ii Natural Resources Canada, “Backgrounder Chrysotile in Support of the Consultation Document on the Addition of Chrysotile Asbestos to the PIC Procedure of the Rotterdam Convention” , February 26, 2004. p.1,2
iii United States Environmental Protection Agency , “The ABCs Of Asbestos In Schools”, Washington: Office of Pollution Prevention and Toxics, August 2003, EPA-745-K93-017, p. 4
iv Health Canada, “Health Risks of Asbestos” , Canada, September 2005, ISBN # 0-662-36886-X, p.2
v U.S. Department of Health and Human Services, “Public Health Statement for Asbestos” , Atlanta: Agency for Toxic Substances and Disease Registry, September 2001, CAS# 1332-21-4
vi Ontario, “Ontario Regulation 278/05 Designated Substance: Asbestos on Construction Projects and in Buildings and Repair Operations” , 2005, O.Reg 278/05 18(6)5
vii Carleton University, “Asbestos Management Policy”
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