HVAC and COVID-19 Guidance
How IPF is addressing building air quality
IPF is following guidance from the Centers for Disease Control and Prevention (CDC), the U.S. Occupational Safety and Health Administration (OSHA), and the American Society of Heating, Refrigerating and Air‐Conditioning Engineers (ASHRAE) guidelines for ventilation and filtration.
We also are closely reviewing CDC guidance regarding how COVID-19 spreads along with our partners in Environmental Health and Safety and other campus units.
Recommendations from ASHRAE, CDC, OSHA and MIOSHA as of early June 2020:
- Increase outside (ventilation) air: ventilation based on ASHRAE standard 62.1; run systems with additional fresh air if available as a purge two hours before and after occupancy.
- Keep systems running longer hours: run systems 24/7 as applicable, i.e. where systems and outside air dampers are not controllable.
- Disable DCV (Demand Control Ventilation) that would lower outside air below ASHRAE 62.1 level.
- Increase filtration to MERV 13: not required on 100% outside air buildings. Some campus buildings are already at or above the recommended level.
Temperature and Humidity Control
- Maintain temperature and humidity as applicable to infectious aerosol of concern: To be done within the constraints of the existing building systems so we do not create uncomfortable working conditions inside facilities or create conditions that would promote the potential growth of mold.
- Add additional measures for areas of high respiratory activities or with less than ideal ventilation.
What is IPF doing to increase outdoor air ventilation in my building?
IPF is following guidance from the Centers for Disease Control and Prevention (CDC), American Society of Heating, Refrigerating and Air‐Conditioning Engineers (ASHRAE), and U.S. Occupational Safety and Health Administration (OSHA) guidelines for ventilation.
IPF has implemented the CDC’s ‘Interim Guidance for Businesses and Employers Responding to Coronavirus Disease 2019’ from May 2020. IPF is also following the expert guidance of ASHRAE (American Society of Heating, Refrigeration, and Air Conditioning Engineers) through their Position Document on Infectious Aerosols.
Using building mechanical system economizers and addressing under‐ventilated spaces, IPF has worked to improve indoor air conditions starting with classroom facilities.
These facility modifications will be balanced with indoor space temperature and humidity conditions so we do not create uncomfortable working conditions inside or create conditions that would promote the potential growth of mold. This is part of a multi‐pronged approach to help manage the risk of COVID‐19 in spaces across the university where people are together for extended periods of time.
Does COVID-19 spread through building mechanical systems?
Based on numerous studies, MSU does not believe that the virus can be effectively transmitted through a building’s central mechanical system.
Multiple studies have identified that, while transmission is theoretically possible, the risk of transmission seems improbable. Taylor Engineering, a private engineering firm, performed a review of more than 80 research reports and concluded that none of the studies demonstrated transmission through central air handling systems.
Despite this evidence, there is not enough information to conclusively state that the virus cannot be transmitted through heating, ventilation and air conditioning systems. Out of an abundance of caution, MSU is following a multi‐pronged approach consistent with all applicable CDC guidelines, as well as ASHRAE guidance to help prevent the possible spread of COVID‐19.
What is IPF doing to improve filtration in university facilities?
IPF has added high‐efficiency filters in accordance with the latest CDC and ASHRAE guidance. Some filters were already at or above the level recommended by ASHRAE and the CDC.
IPF is following the guidance of ASHRAE through the Position Document on Infectious Aerosols. This document identifies that the use of highly efficient particle filtration in centralized HVAC systems reduces the airborne load of infectious particles. As a result, ASHRAE’s recommendation, as well as the recommendation of the CDC, highlights the use of high‐efficiency filters.
The replacement of the filters is part of a multi‐pronged approach to help manage the potential risk of COVID‐19 in spaces across MSU where people may be together for extended periods of time.
Is my window air conditioner safe to use?
Using a window air conditioner in a space with a single occupant is safe to use.
MSU has not found any research that shows the virus is viable after recirculating through a piece of HVAC equipment at this time. However, since window air conditioners only recirculate room air and do not bring in additional outside air, it is best to err on the side of caution and not use them in rooms with multiple masked people.