Can COVID spread through vents?

Can COVID spread through vents?

Welcome to “Ask Deb from QA,” a new column from MxD.

Every week, Deb from QA — with decades of experience on the factory floor — will answer your questions to demystify and explain the digital manufacturing industry.

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Updated October 7, 2021.

Dear Deb from QA: I work in a factory that recirculates a lot of cold air. Does that make my workplace more susceptible to the coronavirus?

Exactly how COVID-19 spreads has been one of the most vexing questions during our current crisis. According to the World Health Organization, the virus is thought to spread mainly between people who are in close contact with one another (within 3 feet), when aerosols or respiratory droplets from an infected person are inhaled or come into direct contact with someone else’s eyes, nose, or mouth. 

People with COVID can spread it to others by coughing, sneezing, talking, or singing.  

COVID-19 also can spread in poorly ventilated and/or crowded indoor settings where people spend longer amounts of time. That’s because, WHO says, aerosols can stay suspended in the air or travel farther than 3 feet.

That “poorly ventilated” part has lots of folks asking if the virus can spread through HVAC (ventilation systems). Like so much with COVID-19, the jury’s still out on that. Or as the CDC says: “The risk of spreading SARS-CoV-2, the virus that causes COVID-19, through ventilation systems is not clear at this time.”

Researchers at the University of Florida last year found what has been called “unambiguous evidence” of live virus circulating through the air – up to 16 feet away from patients hospitalized with COVID-19. 

Then there’s this from the CDC’s Emerging Infectious Diseases, about COVID-19 aerosol found near air vents of intensive care units in China. Of course, these happened in hospitals with patients infected with the coronavirus, and that’s a different scenario from a large factory with recirculated air. 

The CDC has advice about how to improve ventilation in a closed space like a factory or building. One key piece of advice: bring in more outdoor air, either by opening windows and doors, using fans, or rebalancing the HVAC system.

Even if your company is willing to reconfigure HVAC units to bring in more fresh air (MxD’s building, for example, is now being supplied with double the fresh air), that’s likely going to take some time since – aside from opening windows – these measures are not cheap

In this case, the easiest answer remains the best answer: Vaccinated or not, wear a well-fitting, multi-layered mask. Wash your hands. Abide by social distancing protocols.  

The Occupational Safety and Health Administration (OSHA), in addition to recommending that workers get a COVID-19 vaccine as soon as possible, suggests that you participate in any training offered by your employer or building manager to learn how rooms are ventilated, encouraging your employer to provide training if it doesn’t exist. 

And in the see-something-say-something department, OSHA says to alert the building manager if you see clogged or dirty vents or vents that are blocked by furniture or equipment.

Until we find out more facts about COVID-19 and air transmission, these steps are an effective way to combat the virus’s spread. And it’s something that you, yourself, can control.

Assuring quality,

Check out last week’s Ask Deb here:
Where are manufacturing jobs?

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