Wear a mask. Wash your hands. Maintain a social distance of six feet. These Centers for Disease Control and Prevention guidelines have become part of most Americans’ day-to-day routine in the past six months. 

But another important, and sometimes overlooked, factor when it comes to preventing the spread of the virus is indoor air quality and ventilation. Researchers have increasingly called for measures to ensure proper ventilation, especially in businesses and schools. These measures include increasing outdoor air circulation in buildings and making sure air filters are up to grade.

This comes after additional evidence that the virus can be transmitted through droplets in the air, especially with prolonged exposure to the pathogen. In fact, the CDC first found air conditioning’s ability to spread the coronavirus in late January after an asymptomatic patient transmitted the virus to 10 people in an air-conditioned restaurant.

With cold weather approaching in Michigan, more students are bound to study and socialize indoors, making good ventilation even more essential.

So, what is the University of Michigan doing to ensure good ventilation? 

‘A layered approach’

The Michigan Daily spoke with health experts at the University, who said good ventilation is just one part of a “layered approach” to preventing COVID-19. 

Steve Brabbs, director of Maintenance-Regions & Work Management, is a member of the University’s task force that oversees Heating, Ventilation and Air Conditioning systems. 

Maintenance-Regions provides the University building maintenance, while Work Management oversees all concerns and is responsible for preventive maintenance planning and quality assurance inspections. 

“While robust ventilation is important, and is part of our layered approach to campus health and safety, the use of face coverings, social distancing, proper hand hygiene and reduced density are of the utmost importance in preventing the spread of COVID-19,” Brabbs said.

The University’s task force is charged with conducting ongoing reviews of CDC recommendations, best practices and standards for the University’s HVAC systems throughout the pandemic, according to an Environmental, Health & Safety guideline report. 

According to Brabbs, the task force consists of 11 people and was formed in early June. This force is composed of operations managers, certified industrial hygienists, registered professional engineers and building code officials all employed by the University. The team also has multiple members from the Office of Campus Sustainability.

Increasing airflow

The CDC recommends increasing the total airflow supply and percentage of outdoor air to occupied spaces. 

According to John Healy, director of Student Life Auxiliary Facilities & Capital Projects, “Outside air can be considered COVID free.”

The University has maximized outdoor air rate and increased total airflow where possible, according to Brabbs and the EHS report. The exact percentage of outdoor air coming in depends on outdoor conditions and temperatures, but Brabbs said the forced air systems, or a type of ventilation system that uses fans or blowers to provide fresh air to rooms, are always taking in some outside air, though it is limited by extreme temperatures. 

Research buildings, such as the Chemistry Building and the Undergraduate Science Building, were already at 100% outdoor air in accordance with U-M Design Guidelines, Brabbs said. 

Brabbs said maintenance personnel perform preventative maintenance and inspections on air handlers across campus in almost equal amounts every month. According to Brabbs, thousands of these preventive maintenance inspections are done a year on ventilation systems alone.

While there has not been any need for additional maintenance, Brabbs said one of the operation and maintenance engineers proactively performed inspections of air handlers and filter racks in important locations as activity resumed following the reduction in operations in March and April.  

According to a Wall Street Journal article, starting HVAC systems earlier than usual will allow more time for airflow and filtering before occupants enter the building.

Brabbs said maintenance extended the scheduled runtimes of the fans both before and after University buildings were occupied so that they would “pull in that much more fresh air.” Even the ventilation schedule in areas of buildings that aren’t being used had set minimum run times of at least two hours in the morning and evening. 

Christopher Godwin is a research scientist in the School of Public Health whose area of expertise is indoor air quality and exposure assessment. Goodwin said he felt that the measures being taken by the University were effective.

“It’s not a matter of either-or, it’s all of the above and everything you can do to reduce the amount of virus that gets into the air,” Godwin said. “It’s a matter of what (the University) can do given the infrastructure that they’re working with.”


What about residence halls, which have less used common areas and more individual spaces? 

According to Healy, inspections in residence halls are also performed quarterly. In the residence halls, inspections and any maintenance on the air handling systems was done in the summer and will be done again in November and December.

The newer and remodeled residence halls have 100% outdoor air during moderate temperatures, which Healy said is typically set around 50-70 degrees. Students’ rooms with fan coil units do not bring in outside air, though Healy said they have filters that are inspected and changed on a yearly basis. This filter replacement occurs when student rooms are not occupied. 

Older residence buildings, such as Martha Cook, Helen Newberry and Betsy Barbour, do not have forced air ventilation in common areas and, instead, they rely on windows or building leakage for outside air.

Students living in Mary Markley and staff members at the dorm were told to not attend in-person classes and asked to follow enhanced social distancing for the 14 days following 17 new cases identified on several floors in the dorm on Oct. 17. 

According to Healy, Markley’s HVAC system is “relatively modern” in comparison to the systems in Martha Cook and Newberry, with student rooms being tempered in the winter months through a hydronic, or hot water, heating system as opposed to steam heat. Residential halls such as Bursley and South Quad also use a hydronic heating system, while the older buildings mentioned before use steam heat. 

Healy said both of these types of buildings do not have forced air ventilation or a fan coil, so there is no forced air to filter. New and recently remodeled residential halls such as East Quad, Alice Lloyd, West Quad, North Quad and Mosher-Jordan have forced air in common areas, but student rooms do not have this forced ventilation.

Daily Staff Reporter Iulia Dobrin can be reached at idobrin@umich.edu

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