Contact usF.A.Q.LinksNewsAbout the Institute FrançaisEspañol  

The vermiculite >>
Rotterdam Convention >>

Asbestos in buildings

 Print version

you are here: Asbestos in your home / Asbestos in buildings

Practical guidelines for building owners

Prepared for
The Asbestos Institute

By
M.F. (Pierre) Girgis, M.A.Sc., P. Eng.
President, Girgis Environmental Consultants Inc.
Markham, Ontario
Canada

CONTENTS

Inventory of materials suspected of containing asbestos in a building
Assessment of asbestos-containing materials
Implementation of corrective measures
Operation and maintenance programs
Asbestos-related training
Surveillance

Overview

Friable asbestos-containing materials are present in many public and commercial buildings, schools and factories built before the mid-70's. Regulations in Ontario and some other provinces require building owners and property managers to put in place asbestos control programs, once they are aware of the presence of friable asbestos-containing materials in their buildings.

 TOP

In developing an asbestos control program, one or more of the following tasks should be undertaken:

  • Conduct a survey of asbestos-containing materials in the building;
  • Assess the asbestos in the building and establish the most appropriate measures to control potential exposures;
  • Execute corrective measures, if required;
  • Establish asbestos-related operations and maintenance procedures;
  • Obtain proper equipment and supplies;
  • Provide training to all parties involved with the asbestos control program;
  • Conduct periodic surveillance of asbestos-containing materials in the building and execute all necessary corrective measures, if required.

A.   Inventory of materials suspected of containing asbestos in a building

The following tasks should be performed by a qualified survey team:

  • Study floor plans and specifications;
  • Investigate the different phases of construction, additions and the history of major renovation work;
  • Design a bulk sampling program, including the location and the number of representative samples required for each application. Establish the number of duplicate and composite samples needed to produce a complete survey;
  • Bulk samples should be analyzed by an accredited laboratory with proper quality control procedures:

    • The analytical report should indicate:

    • Whether or not asbestos is present;
    • If present, the type of asbestos and the percentage of asbestos and other materials in the sample;
    • The identification method used and the accuracy of the method.

  • An extensive survey of non-friable materials suspected of containing
    • asbestos is not commonly included in the overall asbestos survey except in the case of major potential disturbances during planned renovation or demolition activities.

 TOP

B.   Assessment of asbestos-containing materials

After the locations of the asbestos-containing materials have been identified, physical inspection and assessment of these materials are required.

Evaluation of the potential hazard presented by friable asbestos-containing materials in the buildings involves appraisal, by trained observers, of a number of factors:

These factors generally include:

  • The likelihood of fibre released from the asbestos-containing material. This can be assessed by evaluating its current condition and the potential for future disturbance, damage or erosion.
  • The type of asbestos and the percentage of asbestos in the material.
  • Friability of the material (cementitious or fibrous).
  • Level of accessibility by the building occupants and the maintenance personnel.
  • Signs of water damage.
  • How much vibration the material is subjected to under normal operating conditions.
  • Level of activity in the immediate area.
  • Presence in an air plenum direct air stream
    • .

The following conditions should be documented if present:

  • Missing sections of sprayed-on fireproofing or thermal insulation.
  • The extent of the existing damage.
  • Fallen asbestos-containing insulation materials on surrounding surfaces.
  • The presence of pieces hanging loose from asbestos-containing materials.

Investigate

  • The potential causes for observed damage
  • Potential disturbance by normal operation and maintenance activities

Review future renovation plans.

Determine:

  • The need for further action.
  • When it would be done.
  • What abatement method should be used.

The assessment can be conducted by the same personnel responsible for the building survey to provide the most cost-effective approach.

Based on this assessment, the scope of the asbestos control program can be established.

 TOP

C.   Implementation of corrective measures

Corrective measures, if required, may include one or more of the following:

Repairs
Repair of thermal insulation includes the restoration of asbestos-containing insulation, or the covering material, that has been damaged, usually located on pipes, boilers, tanks, ducts or other facility components.

Enclosure
Enclosure involves construction of airtight walls and ceilings around the friable asbestos-containing materials.

This option can only be selected if repair or removal of the asbestos-containing materials is not practical.

Encapsulation
Encapsulation involves the application of an encapsulant to friable asbestos-containing materials to control the release of asbestos fibres in the air.

The encapsulant creates a membrane over the surface (bridging encapsulant) or penetrates the material and binds its components together (penetrating encapsulant).

Encapsulation is not applicable if the materials is deteriorated or has insufficient adhesion.

The encapsulation option can only be selected for limited size areas where complete removal is not warranted or practical.

Note:
The use of encapsulation or enclosure, on a large scale, should be studied carefully for each application to ensure applicability and valid economics.

Removal
Asbestos removal activities involve the stripping of deteriorated friable asbestos-containing materials from surfaces or components of a facility, and the replacement of insulation.

Removal of friable asbestos-containing materials should take place only when:

  • The asbestos-containing materials are damaged beyond repair.
  • The disturbance of the asbestos-containing material cannot be controlled with operating and maintenance procedures.
  • Otherwise, removal activities should be built into major renovation plans, or take place just prior to the demolition of the building.

When the decision is made to remove friable asbestos-containing materials, detailed site specific specifications have to be prepared, by qualified personnel, to ensure the safety and health protection of building occupants and workers who are executing the abatement activities.

 TOP

The following factors should be taken into consideration:

  • How to incorporate abatement activities with other activities, such as renovation or major repair work.
  • How to stage abatement activities in the most practical and economical manner.
  • How to minimize disruption of the activities of the building.

Removal of friable asbestos insulation materials is a dangerous process that should be planned for and executed carefully by a competent and qualified team. Both the consultant and the contractor should have a properly trained work force.

Potential difficulties and problem areas during the removal process should be anticipated and planned for before starting any asbestos abatement activity.

Regulations provide general guidelines for asbestos control which are applicable to a wide variety of situations. Accordingly, site specific specifications are required to translate these regulations to the abatement project being considered and to specify the level of performance to be achieved during and after the completion of the abatement activities.

Air monitoring during asbestos removal is required in many cases, including:

  • Inside the removal enclosure, to ensure that fibre counts are below the maximum allowable concentration levels, taking into consideration the protection factor of the respiratory equipment used.
  • Outside the removal enclosure, to ensure that the removal process has no adverse impact on the fibre concentration levels in the occupied sections of the building.
  • At the completion of the removal and cleaning process as proof of performance (clearance level).

Typically, the removal of sprayed-on fireproofing material containing asbestos and the replacement cost, is about 10 to 15 dollars per square foot. However, this cost can be significantly higher if there are many restrictions on the execution of the work.^

With respect to high density non-friable asbestos-containing products, such as asbestos-cement cladding, pipe, roofing tiles, vinyl floor tiles, gaskets and packings and friction materials, regulations require only simple, straight-forward workplace practices and procedures when installing, repairing or removing these materials.

 TOP

D.  Operation and maintenance programs

The purpose of the Operations and Maintenance Program is to ensure that appropriate precautionary measures are taken by maintenance and custodial workers, and outside contractors, when undertaking activities which could potentially disturb asbestos-containing materials.

The elements of the program include:

  • Notification of the building occupants of any work which may disturb asbestos.
  • Informing in-house maintenance and custodial workers and outside contractors of the location of asbestos-containing materials.
  • Ensuring that all parties involved in the control program, including outside contractors, are informed of any planned potential disturbances of asbestos-containing materials.
  • Application of safe work procedures for planned work and emergency situations.
  • Maintaining proper records pertaining to asbestos control.
  • Ensuring that any workers, who may disturb asbestos-containing materials, have received proper training.

A site specific Operation and Maintenance Manual for each building should be developed by a competent consultant. This manual should be made available to the operation and maintenance staff in the building, or any outside contractors, who may disturb asbestos-containing materials, during the course of their activities.

The Operation and Maintenance Manual should contain sections addressing the following topics, as applicable:

  • The management structure of the Asbestos Control Program, which outlines the distribution of tasks, authorities, and lines of communications
  • The procedures for planned repair or removal of thermal insulation containing asbestos, including glove bag techniques
  • Procedures for emergency repair or removal of thermal insulation containing asbestos on pipes and fittings: cold systems, hot systems
  • The application of encapsulants
  • Enclosure of friable asbestos-containing material
  • Cleaning of dust and debris containing, or suspected of containing, asbestos
  • Procedures for the disposal of asbestos waste
  • The operation, care and maintenance of HEPA vacuum units
  • The fitting, use and care of respiratory equipment
  • List of applicable equipment and supplies to be maintained in the building
  • Maintenance of records

The cost of implementing an effective Operation and Maintenance Program, to control potential asbestos exposure in a building is fairly small, in comparison with the potential cost of complete removal. Accordingly, removal of asbestos-containing materials should only be considered when no other options are applicable.

 TOP

E.   Asbestos-related training

Training courses will be required for all participants in the Asbestos Control Program. These may include:

  • Members of the property management group
  • Maintenance supervisors
  • Maintenance staff

Each of the above groups should be introduced to all the subjects listed below. The scope and duration of the training course will depend on the requirements of each group and their role in the Asbestos Control Program.

  • Potential hazards associated with exposure to asbestos fibres
  • The location of asbestos-containing materials in the building
  • Applicable asbestos regulations
  • Personal protection
  • Proper handling of asbestos-containing materials
  • All the procedures listed in the Operations and Maintenance Manual
  • Asbestos waste disposal
  • Maintenance records

The asbestos training course to be given to the maintenance staff should include, hands-on instruction on the following subjects, where applicable:

  • Personal protection
  • Repair of thermal insulation containing asbestos
  • Emergency removal of asbestos-containing material
  • Removal of thermal insulation by glove bag techniques
  • Response to asbestos-related spills or incidents
  • Building of small enclosures for minor removal of friable asbestos-containing materials
  • Maintenance and care of asbestos control equipment

 TOP

F.   Surveillance

Surveillance (periodic assessment) should be performed on all friable asbestos-containing materials, which remain in the building.

The items to be included in the surveillance program should be established after the initial survey, assessment, and corrective measures have been undertaken.

All enclosed and encapsulated asbestos-containing materials should be included in the surveillance program.

The frequency of surveillance is dependent on a number of factors, such as, the condition of the materials, accessibility, level of activity in the area, etc.

Corrective measures, if required, should be executed according to appropriate procedures, immediately following any surveillance program.

Regular surveillance programs are required as long as there remain friable asbestos-containing materials in the building.

 TOP

See also...

Health effects - A.I. research
Safe use manual

Institut du CHRYSOTILE Institute © 1999-2005 All rights reserved
Legal notice | Sitemap