Policy Statement

It is the policy of the City of Toronto to:

  • eliminate, or minimize to the extent possible, the potential for worker, tenant and public exposure to mould in City-owned or leased facilities, thereby protecting their health,
  • preserve the capital investment of City owned facilities by reducing property damage due to water damage and mould growth, and
  • maintain compliance with legislative requirements under the Occupational Health and Safety Act by appropriately managing mould in buildings.


This policy applies at all City-owned or leased facilities.

It applies to all employees, supervisors and contractors engaged in facility management services for the prevention or remediation of mould.


Qualified person

A person who is qualified, by training and experience, to perform the work. In the case of mould remediation work, it would include someone who is knowledgeable of Health Canada’s Fungal Contamination in Public Buildings: Health Effects and Investigation Methods, and the Environmental Abatement Council of Ontario (EACO) Mould Abatement Guidelines (2015), or equivalent.

Water episodes

Incidents or conditions that result in excessive moisture within a building (e.g. flooding, leaks, water intrusion, condensation, etc.)

Mould remediation

Removal of mould using work procedures appropriate to the level of mould contamination that protect occupants and remediation workers from exposure to mould.


Division heads will ensure that:

responsibilities for mould management are clearly established and communicated for all plants/facilities/complexes/buildings, including multi-tenanted locations.

Management of divisions which acquire and maintain City-owned facilities will establish a system to ensure the following steps are taken:

  • When purchasing, leasing or otherwise acquiring facilities, every reasonable effort is made to ensure that acquired buildings are free of active mould growth. In circumstances where a prior mould issue is identified, records of measures taken to address these issues are obtained, wherever possible. At a minimum, mould inspections are performed by a competent person prior to acquisition and mould remediation is completed prior to building occupancy, wherever possible.
  • When purchasing, leasing or otherwise acquiring facilities, every reasonable effort is made to ensure that infrastructure and grading of acquired buildings are not susceptible to water/moisture intrusion, and in circumstances where such deficiencies are known, action will be taken to eliminate such water/moisture intrusion.
  • Employees who work in the vicinity of mould-containing material, including employees of contractors, are advised of its presence.
  • All employees likely to be engaged in mould remediation are trained in (i) mould hazards, (ii) use, care and disposal of protective equipment, and (iii) appropriate work practices. See Appendix A for additional details.
  • All employees likely to be engaged in mould remediation are respirator fit tested for those respirators required to be worn during the work they perform. The appropriate respiratory protection recommended for various levels of mould remediation work are included in Appendix B “Recommended Procedures for Mould Remediation”
  • Training of those managers and staff who have duties and responsibilities under the mould management program is provided.
  • Training records are maintained and retraining is completed on a routine and as-needed basis.
  • Staff who may perform limited mould abatement are supervised and provided with all required equipment and supplies.
  • Periodic routine inspections of the building are performed by a qualified person, including checking for signs of water intrusion, moisture or water damaged materials, and presence of mould growth.
  • Periodic routine inspections of HVAC equipment are performed by a qualified person.
  • Reports of building and HVAC inspections, where available, are provided to joint health and safety committees/representatives, upon request. In Long Term Care Homes, the Health Care and Residential Facilities Regulation requires that inspections be conducted at least once every six months and that results of the inspection be provided to the joint health and safety committee/representatives.
  • A water episode logging system is developed and implemented (see Appendix C), and corrective measures are taken to address the water source.
  • Any incidents of mould growth are promptly remediated and the source of water entry identified and corrected.
  • Prior to any remediation work, consideration must be given to the potential presence of other environmental hazards, such as asbestos, lead or other hazardous material. The Designated Substances or Hazardous Materials Inventory report must be reviewed prior to the work to determine the potential presence of a designated substance or other hazardous materials in the mould remediation work area and implement the appropriate control measures.
  • Inspection frequency is increased following any incidents of mould growth, to ensure that resulting remedial measures have been effective and that no further mould growth is occurring.
  • Prompt response to any reports or indications of potential mould growth (e.g. water stains, musty odour, complaints of poor indoor air quality). Engage assistance of occupational health and safety staff, as required.
  • Repair orders, generated as a response to recommendations of joint health and safety committees, building users, health and safety staff and/or those employees who conduct periodic routine inspections, are promptly addressed (e.g. drying initiated 24-48 hour after leak, flood or water intrusion).
  • Written notification is provided to senior on-site managers prior to initiation of scheduled mould-remediation work. When work is of an emergency nature, E-mail notification is provided.
  • Mould remediation work is classified and appropriate work procedures are developed and implemented in accordance with industry accepted standards or guidelines such as the Environmental Abatement Council of Ontario Guidelines 2015, or equivalent (OHSWC Occupational Hygiene staff can assist). Recommended remediation procedures, based on the extent of mould contamination, are attached (Appendix B).
  • When conducting mould remediation, avoid the unnecessary use of chemicals, such as biocides and sealants, which may adversely affect the health of occupants of adjacent spaces.
  • If the work of service providers may result in disturbance of mould-containing materials, they are advised of the existence of such materials, as well as required work protocols and procedures.
  • If the nature of the work of service providers may result in discovery of sources of mould growth, communicate to these service providers an expectation that any evidence of mould growth observed by service providers will be reported to the City.
  • Outside contractors retained for mould abatement work and their staff are competent.
  • Project managers who oversee the work of mould abatement contractors are appropriately trained and competent.
  • Funds are budgeted for mould remediation projects deemed necessary as a result of mould inspections. If maintaining a facility for another City division where remediation is required, that division’s senior manager is advised of the need to budget for remediation.
  • For leased facilities, participate in discussions with the property management regarding investigation and abatement of mould growth, as required. Include health and safety staff in these discussions, as needed.
  • Qualified consultants are retained to inspect and monitor mould remediation projects that are classified as Level 2 or higher (i.e. extensive and possibly large areas of contamination), and also possibly in sensitive areas (i.e. Children Services, Long Term Care Homes) for certain Level 1 Remediation work.
  • Air sampling following Level 2 or higher mould abatement work is conducted, in accordance with accepted guidelines, as appropriate to monitor the effectiveness of abatement procedures. Air monitoring may also be required following Level 1 Remediation work in sensitive areas.

Management of all divisions that occupy buildings where active mould growth is present or suspected will:

  • Promptly notify facility management of any water episodes (e.g. leaks, spills, seepage, flooding), requesting investigative and/or corrective action within 24-48 hours. Ensure log is completed for these episodes. Water Episode Log Template included in Appendix C is provided as an example.
  • Promptly notify facility management of any reports or indications of potential mould growth (e.g. water stains, musty odours, indoor air quality complaints) as found.
  • Develop, in consultation with health and safety staff, job-specific safe working procedures for work in the vicinity of active mould growth.
  • Schedule with health and safety staff mould training, as necessary, of (i) workers who may work in close proximity to areas with mould growth and (ii) joint health and safety committee members who may visually inspect accessible areas in proximity to where mould growth is. Mould Fact Sheet as attachment Appendix D may be useful
  • Advise employees, tenants and the joint health and safety committee/representative of any investigations of potential mould contamination and results thereof.
  • Advise employees, tenants and the joint health and safety committee/representative of any scheduled or emergency mould-related investigative or remediation work. Provide a copy of any test reports to the joint health and safety committee/representative and notify workers potentially exposed.
  • Report and take/seek corrective action, as appropriate, if concerns are raised or if any violations of safe working procedures are noted during mould remediation.
  • Ensure that source of the indoor moisture/water intrusion problem is corrected so as to prevent a reocurrence of mould growth.

Facilities Management staff, upon notification of a water episode (e.g. leaks, spills, seepage, flooding), will:

  • initiate an investigation and corrective actions as appropriate
  • co-ordinate mould remediation work using qualified personnel and service providers
  • communicate with affected building occupants of investigations and any mould remediation work, and results thereof
  • investigate and initiate action to correct source of the water intrusion (i.e. leak, seepage, flooding, spill).

The Occupational Health, Safety and Workers’ Compensation Unit’s occupational hygiene staff will:

  • Lead in the development of procedures, guidelines and training programs to facilitate compliance with this policy.
  • Provide, or assist in provision of, mould awareness training for those employees potentially exposed to mould or are engaged in inspection of buildings, facilities and response to mould related concerns.
  • Assist in addressing employee mould-related concerns.
  • Assist divisions in mould-related communications with the Ministry of Labour.

Occupational health and safety consultants will:

  • Based on joint health and safety committee inspection reports and/or their own inspections, recommend appropriate remedial actions or seek an occupational hygiene assessment.
  • Assist in the provision of training and development of safe work procedures.

Joint health and safety committees/Occupational health and safety representatives will:

  • Document evidence of any water episodes (e.g. leaks, spills, seepage, flooding) or other indications of potential mould growth (e.g. water stains, musty odours, indoor air quality complaints) as part of their routine workplace inspections.
  • Bring deficiencies, if any, to the attention of area supervisors and occupational health and safety staff.

Workers will:

  • Work in a manner that does not contribute to the development of mould-related problems, by following identified safe work procedures.
  • Follow safe work procedures applicable to any mould remediation work they perform.
  • Advise their supervisors of any mould-related occupational health and safety issues or concerns (e.g. visible signs of potential mould growth or symptoms that could be related to mould exposure in the building).
  • Report water leaks, spills or signs of water intrusion to their supervisors or where applicable to Facilities Management Division: Custodial and Maintenance Service 338-FRED (338-3733)

The Occupational Health and Safety Co-ordinating Committee will:

  • Monitor the implementation and effectiveness of this policy


The Occupational Health and Safety Act (R.S.O. 1990)
Mould in Workplace Buildings. Ministry of Labour Alert. ISSN: 1195-5228 issued Dec 2000; reviewed May 2015
Fungal Contamination in Public Buildings: Health Effects and Investigation Methods, Health Canada 2004
Guidelines on Assessment and Remediation of Fungi in Indoor Environments.
Environmental Abatement Council of Ontario Mould Abatement Guidelines, 2015

Appendix A

Mould Management Training Guideline

Training is to be provided to employees prior to assigning them mould removal work. At a minimum, mould removal training should include the following components:

  • legislative perspective (including Ministry of Labour Alert regarding Mould in Workplace Buildings)
  • City’s Mould Management Policy and its attachments
  • accepted industry standards (referenced in Ministry of Labour Alert)
  • causes of moisture intrusion and mould growth
  • summary of health concerns related to mould exposure
  • identification of the levels of mould remediation and the specific work procedures, practices and methods required for each
  • personal protective equipment required for level of mould remediation to be performed by the employees
  • use, care and fit of the required personal protective equipment, including respirator fit testing

Representatives of contracted remediation services must be trained about the hazards of mould and mould remediation control measures, and be prepared to provide records of such training, upon request.

Awareness level training should be provided to employees and supervision of staff who are responsible for building maintenance, or who are expected to inspect, respond or engage a third party service party to carry out mould remediation. In addition mould awareness training should be provided to employees who express concern because mould remediation work is being performed in or adjacent to their work area.

All training courses must be documented using a sign-in sheet or log with the name of the training program, the date delivered, and the names of the instructor and attendees.

Appendix B


The following procedures are presented as a guide. Comprehensive site-specific technical specifications for the removal of mould-contaminated material may be required for extensive removals. All remediation workers should understand the specifications before attempting to remove mould-contaminated material.

In all situations, the underlying cause of water moisture/intrusion must be rectified or fungal growth will recur. Any initial water infiltration should be stopped and cleaned immediately. An immediate response (within 24 to 48 hours) and thorough clean up, drying, and/or removal of water damaged materials will prevent or limit mould growth. If the source of water is elevated humidity, relative humidity should be maintained at levels below 60% to inhibit mould growth. Emphasis should be on ensuring proper repairs of the building infrastructure, so that water damage and moisture buildup does not recur.

The goal of remediation is to remove or clean contaminated materials in a way that prevents the emission of mould and dust contaminated with mould from leaving a work area and entering an occupied or non-remediated area, while protecting the health of workers performing the remediation. The remediation methods described below were designed to achieve this goal, however, due to the general nature of these methods, it is the responsibility of the people conducting remediation to ensure the methods enacted are adequate. The remediation methods outlined below are not meant to exclude other similarly effective methods. Any changes to the remediation methods outlined below, however, should be carefully considered prior to implementation.

General Guidelines

  • Notify affected building occupants of the mould remediation work plan (i.e. timeline, hours of work, precautions required).
  • While removal of occupants from spaces adjacent to the remediation work area is not necessary in all circumstances it may be warranted in circumstances for person(s) recovering from surgery or are immunocompromised, children and the elderly.
  • If feasible, perform remediation after normal working hours when the building is unoccupied. When performing remediation work (see following sections), shut down the heating, ventilating, and air-conditioning (HVAC) system serving the floor or area where the remediation work is performed. Clean all moveable non-porous uncontaminated content items, first with a high efficiency particulate air (HEPA)-filtered vacuum cleaner, and then with a damp (not wet) cloth. Remove these items from the work area before starting the removal of mould-contaminated materials.
  • Non-porous (e.g., metals, glass, and hard plastics) and semi-porous (e.g., wood, and concrete) materials that are structurally sound and are visibly mouldy can be cleaned and reused. Cleaning should be done using a mild detergent solution. If the area has been contaminated with unsanitary water (e.g. sewage) a disinfectant should be used.
  • Porous materials such as ceiling tiles, insulation, and wallboards that have been affected by unsanitary water must be removed and discarded. Porous materials (e.g., fabrics) affected by clean water can be cleaned, can be reused, but should be discarded if possible. All materials to be reused should be dry and visibly free from mould.
  • Except in cases of extensive microbial contamination (e.g., sewage backflow, as part of a remediation and clean-up process), do not apply disinfectant to mould-damaged materials. The use of biocides in this manner can pose health concerns for remediation workers as well as for people in adjacent occupied spaces. Furthermore, the use of biocides does not address the possible health concerns from the presence of remaining non-viable moulds. If disinfectants are applied in a liquid state (mixed with water), the elevated moisture content that may be left as a residue in porous materials (after the disinfecting agent has dissipated) may subsequently cause new microbial growth.
  • Avoid the use of unnecessary sealants, glues (except for affixing containment barriers to walls), solvents or other chemicals which may impact the health of building occupants. In the event that their use is required, advise onsite personnel, provide relevant material safety data sheets (MSDSs), and ensure that precautions are taken to minimize health risks to occupants.
  • Limited use of water for cleaning of impacted surfaces is allowed. However surfaces to be cleaned should be damp-wiped and not soaked or sprayed.
  • Stop all work if there is a break in containment barriers. When containment is required, re-seal plastic barriers prior to continuing with remediation work.
    • Conduct evaluations during as well as after remediation to confirm the effectiveness of remedial work, particularly for large-scale remediation.
    • Eating, drinking or smoking is not permitted in the area of mould remediation
    • Dry sweeping is not permitted in the work area. Only vacuums fitted with effective HEPA (High Efficiency Particulate Arrestance (HEPA)-filter dust collection are permitted.

Mould Remediation: Precautions and Safe Work Practices

Levels of safe work practices and precautions for mould remediation are primarily determined by the size of the area impacted by mould contamination. The extent of mould contamination area is usually based on a visual inspection. Air and surface sampling are not required to undertake remediation or determine the mould remediation level.

Described below, based on the EACO Mould Abatement Guidelines 2015 – Edition 3, are guidelines and procedures for three levels of mould remediation work.

Level of Mould Remediation Description Size of Mould Impacted Area
Level 1 Small Isolated Area 1m2 (10 sq. ft) or less of building materials or Clean-Up of <1m2 (10ft2) of mould growth in Heating, Ventilation and Air Conditioning Systems (HVAC) in Non-Occupied Areas
Level 2 Medium Areas 1-10m2 (10-100 sq. ft.) or less than 1m2 (<10ft2) in Heating, Ventilation and Air Conditioning Systems (HVAC) in Occupied Areas
Level 3 Large Areas or More Than 1m2 in HVAC systems Greater than 10m2 (>100 ft2) or Greater than 1m2 (>10 ft2) in HVAC systems

Appendix C

Mould Management Water Episode Log

Tool Kit

Appendix A- Mould Management Training Guide
Appendix B- Mould Remediation Procedures
Appendix C- Water Episode Log
Appendix D- Mould Fact Sheet

Endorsed by:

Occupational Health and Safety Co-ordinating Committee (OHSCC)
September 19, 2006

OHSCC Reviewed and re-approved:

November 26, 2008
February 8, 2017

Approved by

City Manager

Date Approved

January 24, 2007

Reviewed by OHSCC

February 8, 2017

Related links

The Occupational Health and Safety Act (R.S.O. 1990)
Mould in Workplace Buildings. Ministry of Labour Alert. ISSN: 1195-5228 issued Dec 2000; reviewed May 2015
Fungal Contamination in Public Buildings: Health Effects and Investigation Methods, Health Canada 2004
Guidelines on Assessment and Remediation of Fungi in Indoor Environments.
Environmental Abatement Council of Ontario Mould Abatement Guidelines, 2015