Key Points

  • Scientific evidence has shown that the COVID-19 virus can spread in poorly ventilated and/or crowded indoor settings.
  • The World Health Organization (WHO), the US Centers for Disease Control and Prevention (CDC), and members of the scientific community have considered the potential risks that current heating, ventilation, and air conditioning (HVAC) systems pose in spreading the COVID-19 virus.
  • Engineers Canada encourages all governments and businesses to review their HVAC systems, with the help of an engineer, to ensure that it is up to the standards outlined by the Public Health Agency of Canada (PHAC) and the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE).
  • It is vital that federal and provincial governments consult licensed professionals, including engineers, in assessing and upgrading HVAC systems. Consultation with professionals is required when considering changes to HVAC systems and equipment to help maintain good indoor air quality so that the risk of exposure to and spread of the COVID-19 virus remains low.
  • The PHAC and ASHRAE have released several key resources that outline how to improve current HVAC systems, as well as how to properly mitigate the transmission of the COVID-19 virus.

Background

The COVID-19 virus, and other similar pathogens, can spread through various transmission routes, including direct and indirect contact with contaminated surfaces and exposure to respiratory droplets. While not initially considered, additional data has become available from the scientific community that indicates that COVID-19 can also be spread by aerosolized particles and therefore airborne transmission of the virus must also be addressed to curb its spread. The World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) have made explicit references to this concern and have recognized the potential for airborne transmission of COVID-19. The WHO has developed a document entitled: “Roadmap to improve and ensure good indoor ventilation in the context of COVID-19,” which aims to define key questions users should consider to assess indoor ventilation and the major steps that are required to reach recommended ventilation levels to improve indoor air quality to reduce the risk of spread of COVID-19.

Ventilation upgrades and improvements can increase the delivery of clean air and dilute potential contaminants.[1] However, applying tools to improve ventilation, such as adjusting heating, ventilation, and air conditioning (HVAC) systems to increase airflow to different building types, occupancies, and activities under environmental and seasonal changes, can be challenging. The federal government must continue to work with provincial and territorial governments to implement a plan to prioritize and conduct assessments to HVAC systems to adequately address these challenges. Additionally, consultation with experienced and unbiased professionals is required when considering changes to HVAC systems and equipment to help maintain good indoor air quality so that the risk of exposure to the COVID-19 virus remains low.

The Public Health Agency of Canada (PHAC) has developed COVID-19: Guidance on indoor ventilation during the pandemic to inform Canadians about how indoor ventilation, in combination with other recommended public health measures, can reduce the spread of COVID-19. It provides practical tips on how to improve indoor air, ventilation, and filtration to help reduce the spread of COVID-19.

In addition, the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), has also released several key resources that outline how to create improvements to current HVAC systems, as well as how to properly mitigate the transmission of the COVID-19 virus. ASHRAE’s Building Readiness Guide includes an extensive checklist that makes explicit reference to include licensed and certified professionals that can perform the analysis, testing, design, construction, control programming, balancing, commissioning, maintenance, and operation services that are required to make HVAC adjustments and to achieve optimal performance to reduce the spread of COVID-19.[2] The document recommends “consulting with a local professional engineer to determine the appropriate minimum RH levels based on local climate conditions, type of construction and age of the building under consideration.”[3] Engineers Canada strongly agrees with ASHRAE’s guidelines and recommends that all levels of government consult with professional engineers to expertly address HVAC considerations to prevent the spread of COVID-19.

Engineers Canada believes that it is vital for the federal government to be progressive and proactive in its approach to upholding public safety. For this reason, Engineers Canada also recommends that the federal government’s Building management direction for coronavirus disease 2019 (COVID-19), introduced under Public Services and Procurement Canada, be amended to include the need for consultation with professional engineers in the assessments and upgrades of HVAC systems. 

Next Steps

  • Engineers Canada encourages all governments and businesses to review their HVAC systems, with the help of an engineer, to ensure that they are up to the standards outlined by PHAC and ASHRAE.
  • Engineers Canada will continue to monitor and advocate for the involvement of engineers in the changes to HVAC systems and equipment to help maintain good indoor air quality so that the risk of exposure to the COVID-19 virus remains low.

[1] Centre for Disease Control and Prevention (2021). “Cleaning, Disinfecting, & Ventilation.” Retrieved August 16, 2021 from: https://www.cdc.gov/coronavirus/2019-ncov/community/ventilation.html.

[2] American Society of Heating, Refrigerating, and Air-Conditioning Engineers (2020). “Building Readiness.” Retrieved August 16, 2021 from: Building Readiness (ashrae.org).

[3] Ibid.