Air Quality and Ventilation Best Practices
The health, safety, and security of our school community is our foremost priority at Kingsley. This past summer, Kingsley joined a number of leading independent schools in the Boston area to commission Environmental Health and Engineering, Inc., to generate a report bringing together expert guidance across domains and providing more specific operational and policy recommendations, in general. A significant portion of their report pertained to facilities management, and ventilation in particular.
HVAC Expert Guidance
In preparing this report, Environmental Health and Engineering, Inc. analyzed the following sources of expert guidance:
- American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE)
- Centers for Disease Control and Prevention
- Massachusetts Department of Elementary and Secondary Education
Key Recommendations and Responses
The report identified five (5) general recommendations for schools. Kingsley has taken these recommendations under advisement and implemented the following steps in accordance.
- Assemble a team of key individuals and companies who play a role in the setup and operation of building systems.
Kingsley was fortunate in that an overhaul of the HVAC system in the Exeter building had already been planned for the summer of 2020. In many ways, the team was already assembled. The scope of the review was simply expanded to include concerns specific to COVID transmission.
This work and systems review has involved J.C. Cannistraro LLC, JEC Service Company Inc., and Breen & Sullivan Mechanical Services Inc., as well as other architectural and engineering consultations.
- Conduct a walkthrough of spaces that will be occupied to note potential deficiencies in air distribution, such as blocked or partially covered air supplies.
These walkthroughs have been conducted on an on-going basis as work has proceeded on the HVAC system in the Exeter building. Once classroom layouts were determined, another round of walkthroughs was conducted to ensure air distribution is maximized and vents/intakes are still open and accessible.
|Portable UV-C/HEPA Filtration Unit|
Concerns were raised regarding circulation of fresh air in our historic Fairfield building, especially during colder months, when windows may not be comfortably opened. To help address these concerns, HEPA air filtration units were purchased for the building to help remove potential pathogens from the air.
A consulting engineer provided recommendations regarding the number and placement of these units, in accordance with ASHRAE's guidelines. For the most part, the units are located opposite the primary air source such as a vent or an entry door. Each generates at least the minimum recommendation of two (2) air rotations per hour.
To further improve air circulation in the Fairfield building, the central heating system was rewired to allow the system to run and filter air without the heating components engaged. Window-mounted air-conditioning units in the building introduce substantial fresh air while operating. In terms of mitigating the risk of COVID-19 transmission, student workspaces are positioned such that these AC units do not blow directly upon/across an individual child. Combined with the portable HEPA units, these measures allow us to approach or exceed the recommended ideal of 4-5 air changes per hour in Fairfield classrooms.
In the Exeter building, the primary areas of concern were small, enclosed spaces which may be occupied by more than one person at once or in succession. Offices, project studios, and restrooms were of primary concern. Portable air filtration units outfitted with HEPA filters were acquired to supplement air circulation in these spaces, and an electrician was commissioned to install new power outlets where necessary to accommodate these units.
- Perform an and inventory of HVAC systems and document the types and MERV rating of particulate air filters installed in the systems.
Our HVAC contractors have confirmed that our systems in both buildings are equipped with MERV-13 filters, which ASHRAE recommends for COVID mitigation. In response to growing literature and input from the medical community, we investigated adding additional layers of air treatment to our systems, including UV, which have been shown to be effective in destroying the COVID-19 virus.
On the recommendation of our HVAC consultants, we decided upon ionization technology to supplement our systems. In Exeter, GPS-iMod units have been added to the HVAC systems on each floor, and iWave-C units have been added to Fairfield's central system.
These systems create a field of charged particles which both break down and remove particles and pathogens from the air. All of the portable HEPA units acquired this summer include UV-C treatment as an additional measure. HEPA filters are rated even more highly than MERV-13 filters in terms of particle removal from the air.
- Engage a qualified testing, adjusting, and balancing (TAB) firm and or building automation system (BAS) contractor to verify sensor calibration for demand-based ventilation instrumentation, airflow measurement and instrumentation, and temperature control instrumentation.
The Exeter building is equipped with an Automated Logic BAS which allows us to continuously monitor and review system performance. As part of the work completed this summer, system performance was reviewed, and the system itself has been checked to ensure full functionality.
Through the BAS, we have made and will continue to make appropriate adjustments for operations, such as updating schedules of building occupancy to increase before/after hour airflow in accordance with ASHRAE's guidance.
Fairfield's central ventilation system (tied to the heating system) is less sophisticated and does not support BAS controls. However, the system has been reviewed and modified to improve functionality as described below.
- Engage a mechanical service company to inspect and assess the operational capabilities of all mechanical refrigeration equipment, water heaters, steam boilers, pumps, and associated specialties.
Almost all of the critical mechanical parts of the ventilation in Exeter were replaced as part of the system overhaul this summer by J.C. Cannistraro, therefore the parts such as filters, compressors, and fan belts are new and operating as expected. This was confirmed in a subsequent inspection by JEC Service Company, along with the proper functionality of components not replaced as part of the system overhaul.
Fairfield's central heating system has been reviewed and serviced by Breen & Sullivan Mechanical Services and is reported to be functioning properly. Work was completed allowing the system to operate without the heating coils engaged, thereby allowing greater air circulation through its filters, as well as introducing additional fresh air to the building.
In School Recommendations
Teachers are encouraged to keep the following recommendations in mind when managing active classroom spaces:
- Where physically safe and allowed for by climate and weather conditions, windows should be opened to maximize the introduction of fresh air and provide direct ventilation of interior air.
- When opening windows, be particularly aware of any respiratory conditions of students or staff using the space, such as asthma or seasonal allergies. Do not open windows if individuals with such conditions are present.
- Where possible, avoid placing students in the direct path of airflow from vents, fans, or air-conditioning units, which might spread their respiratory droplets further throughout the room.
- Report any concerns you may have about system performance or maintenance to be completed, such as service indicator lights on portable filtration units, or visibly occluded air sources.