Ventilation Archives

• HWDSB initiated a project to have licensed mechanical contractors go through every school and verify ventilation equipment is operating as per manufacturers’ recommendations. The actions undertaken by the consultants include:
  • Check for particulate accumulation on filters, replace filter as needed if material is already on-site. Verify filters are sized and installed correctly. Clean and remove louver obstructions.
  • Check all motors and fans operate correctly. Grease/oil as required.
  • Check belts are tight and in good condition. Replace as required.
  • Check variable-frequency drive for proper operation.
  • Check drain pans for cleanliness and proper slope. Check P-trap on drain pan for proper operation. Clean as required.
  • Verify control dampers operate properly.
  • Confirm equipment is bringing in outdoor air and removing exhaust air as intended.
• Reports for each piece of equipment were received and noted deficiencies were corrected for September 2020. Please see the building specific reports below:

• HWDSB ensured that air was being exchanged, and fresh air was entering occupied spaces.
• We performed “air flushes” of all spaces before occupants re-entered the buildings. This was done daily by having mechanical systems operate in “occupied” mode, which provides ventilation to the building, starting at 6 a.m. before students and staff entered the building. Systems continued to operate in this mode throughout the day.
• In addition, we purchased 150 air purifiers with filters to aid with filtration and ventilation for rooms/areas where there is insufficient air flow.

• HWDSB will continue to ensure that air is being exchanged, and fresh air is entering occupied spaces. Building fresh air was increased where possible through building automation systems to maximize ventilation rates.
• Currently, Board staff is ensuring that “air flushes” are completed daily before staff and students enter the buildings. Air flushes are completed by running mechanical systems two hours prior to, and two hours after leaving. Systems will continue to operate in this mode throughout the day. In addition, filters are changed as required and regular repairs and maintenance is occurring.
• 30 ventilation projects have been funded through the CVRIS program.
• HEPA filter, also known as high-efficiency particulate absorbing filter, units will be provided in accordance with Ministry direction.
• We will continue to plan window upgrades and HVAC projects as part of our regular capital planning with SCI and SRA.

• HWDSB received funding for 30 projects under the COVID-19 Resilience Infrastructure Stream (CVRIS) program. These projects are detailed on the Board website and the stage of the project is identified.
• The projects are a priority for the Board and have had some delays due to supply chain issues. Currently, 26 projects are complete and four are under construction.
• Information on the website will continue to be updated and HEPA air purifiers continue to remain in schools where construction is underway.

HEPA Supply and Distribution

• The Board has 2,453 high-efficiency particulate air (HEPA) filtration units currently deployed in the system, provided in accordance with Ministry of Education direction. This includes all Kindergarten spaces, schools without mechanical ventilation (Tier 3), and where there are active ventilation projects underway and not yet completed. HWDSB has also included gyms and special education rooms, as well as portables and areas not fed from a MERV13 filtration.

HEPA Information

• HEPA units will run while rooms are occupied (all day) and are designed to do so. Capacity depends on fan speed and model ranging from 200-450 CADR.
• The HEPA air purifiers that the Board has are meant to service approximately 1,000 square feet per unit. Classrooms are usually approximately 750 square feet. Therefore, adding additional HEPA air purifiers to a single classroom is not required.
• The filters for the units last approximately 12 months, based on unit filter indicators and run hours. Staff continues to monitor the effectiveness of the filters and change as required.

The Ministry of Education requires school boards to use the HEPA air purifiers provided by, or purchase HEPA air purifiers through, the provincial procurement guidance of the Ontario Government.

From the perspective of fundraising, we are not permitting school councils or individuals to raise funds for HEPA units. In addition to this inventory being under the controlled guidance of procurement practices as well as the enhanced public health efforts, raising funds for these units can create inequity among some school communities. More affluent school communities may be disproportionately advantaged compared to other school communities impacted by lower socio economic conditions.

Also, once we receive any HEPA units, they require filters and the Board would have to include the annual costs of filters in their operating budget moving forward.

• There are three tiers of ventilation as identified by the Ministry of Education. They are Tier 1 (supply, return, exhaust), Tier 2 (supply, exhaust) and Tier 3 (exhaust). Tier 3 schools are typically heated with radiators and have exhaust units for moving air. These schools will be receiving HEPA units.
• The CVRIS projects will upgrade full mechanical systems of six schools and move them from Tier 3 to Tier 1.

• MERV 13 is a rating of filter used in supply and return air systems. Not all systems can accommodate MERV 13, so we have increased the level of MERV where we can.
• Roughly 35% of our schools now operate with MERV 13 filters.
• Roughly 45% of our schools have increased MERV filter values.
• Roughly 20% of our schools (18) are defined as Tier 3 by the Ministry of Education, meaning they have exhaust systems only, which are not mechanically ventilated, and will be equipped with HEPA units.
• More school-specific information regarding filters will be shared in the Standardized Ventilation Reports on September 3.

• Classrooms will not be receiving any additional CO2 monitors if the school’s mechanical systems are not already equipped with them. CO2 monitoring is not required to be installed by Code, but through new construction and renovations, HWDSB follows best practices and installs CO2 monitoring at locations that can benefit from its use.
• CO2 monitors are interlocked with HVAC units, which in turn will increase the amount of ventilation classrooms as CO2 levels increase. Not all HWDSB schools have mechanical ventilation, and therefore would not benefit from CO2 monitoring.
• HWDSB’s CVRIS projects do include the introduction of CO2 monitoring, where applicable. CO2 monitoring is only beneficial in specific mechanical systems, and not all equipment can accommodate them.