Mandate

The National Model Codes Committee (NMCC) on Indoor Environment will address and mitigate risks affecting the indoor environment of new and existing buildings, such as legionella, radon ingress, and aerosol pathogens, through the design and construction of heating, ventilation and air-conditioning (HVAC) and plumbing systems in the National Model Codes as described below and in accordance with the Canadian Board for Harmonized Construction Codes (CBHCC) approved work plan.

Note: the breakdown of mandates shown below does not necessarily reflect the recommended task groups and working groups being planned.

HVAC and plumbing systems in alterations to existing buildings
  • Recommend code changes to integrate requirements on alterations to existing buildings from provincial and territorial jurisdictions in the areas of HVAC and plumbing systems into Part 10 of the National Building Code (NBC) or a new Part in the National Plumbing Code (NPC).
  • Recommend code changes, for any remaining safety considerations associated with piping and venting that are not addressed by the provincial or territorial requirements on alterations to existing buildings, in Part 10 of the National Building Code (NBC) or a new Part in the National Plumbing Code (NPC).
Radon gas mitigation
  • Recommend code changes to the National Building Code to mitigate radon ingress in Part 9 dwelling units in contact with the ground, considering passive and active acceptable solutions, alternate compliance options, effectiveness of poly air barriers, drainage issues in crawl spaces, and application to alterations to existing buildings.
Water quality in water heaters and legionella
  • Recommend code changes in the NPC and Part 7 of the NBC, where appropriate, to address legionella in building water systems for both new and existing buildings.
Air quality, aerosol pathogens (new and existing) and ventilation of care and treatment occupancies
  • Review and assess ventilation system requirements in new and existing buildings, including care and treatment occupancies, to control and reduce the potential transmission of aerosol pathogens, and recommend code changes, where appropriate.
  • Review requirements applicable to indoor air quality in new and existing buildings in response to increased airtightness and recommend code changes, where appropriate.

The NMCC is established by, and reports to, the CBHCC. The NMCC exists until the completion of its mandate or as otherwise directed by the CBHCC.

The NMCC will comply with the Operating Procedures of the Canadian Board for Harmonized Construction Codes.

Responsibilities

In accordance with the mandate described above:

  • develop proposed code changes for consideration for public review by the CBHCC;
    • in developing proposed code changes, consider:
      • harmonization with provincial/territorial variations where possible, if multiple provincial/territorial variations exist seek direction from the CBHCC;
      • code change requests forwarded by the CBHCC;
      • new and existing standards and guidelines; and
      • implications on other code requirements;
    • in developing proposed code changes, identify:
      • impacts of the proposed code changes; and
      • enforcement implications of the proposed code changes;
  • in consideration of public review comments received, recommend code changes for publication, for consideration by the CBHCC;
  • identify where research is needed to support the mandate and support coordination efforts;
  • identify opportunities for coordination with standard development and support coordination;
  • support development of material for the relevant user’s guides and commentaries, where applicable;
  • prepare a final report outlining a brief summary of the deliberations and considerations that led to the recommendation including any outstanding unresolved issues or concerns; and
  • through the Chair:
    • monitor progress against the approved CBHCC work plan and provide regular progress updates to the CBHCC; and
    • participate on the Standing Codes Coordination Committee, to ensure that there are no overlaps with, or conflicts between, the work being developed and that of other committees.