Ithmene air should be controlled by vrunur systems, aerosol researchers say'Ithmene air should be controlled by vrunur systems, aerosol researchers say.

With a new strain of COVID and the start of flu season, now is a good time to pay attention to what the pandemic taught us about preventing the spread of potentially deadly respiratory infections. It turns out that viruses, such as the one causing COVID-19, can travel a much greater distance through the air than six feet. Thus,''Public health advice focused on social distancing, hand washing and wearing masks has been inadequate. Air quality scientists say that from the start of the pandemic, attention should have also been paid to improving the quality of the air we all breathe... indoors.

Some companies are now doing just that - for the health of their workers and their financial bottom line.

Professor Joe Allen of Harvard University's T.H. Chan School of Public Health believes the rapid spread of COVID in early 2020 was preventable. He believes public health has made great strides in the last hundred years in water quality, pollution''outdoor air, food safety and sanitation. However, the issue of indoor air quality was completely forgotten. The pandemic showed how great a mistake that was.

At the start of the pandemic in the U.S., in March 2020, the virus began taking lives in places like the Life Care Center nursing home in Kirkland, Washington.

Sixty miles away, in Mount Vernon, Washington, the Skagit Valley Chorale was holding one of its weekly rehearsals at a church. Half of the choir members stayed home and the other half showed up for the rehearsal. Among them were board members Debbie Amos, Mark and Ruth Beckland and Coisy Bettinger.

None of them anticipated that it wouldn't be enough. A few days later, the choir members started getting sick. A total of 53 people out of 61 fell ill,''who were present that night. Two of them, both in their 80s, died. Skagit County health members said the rehearsal could be considered a "super-spreading event" - one of the first in the country - and concluded that choir members were exposed to "intense and prolonged exposure" to surfaces, droplets and possibly microscopic aerosols containing the virus. This caught the attention of Lynsey Marr, a professor at the University of Virginia Tech, and her fellow researchers. Although the medical community had focused on droplets, surfaces, and hand washing, these researchers strongly believed that COVID was primarily airborne, but they needed more evidence. So they began their own analysis.

Professor'. 'Marr used a portable nebulizer to explain how so many choir members could have gotten sick.

According to Professor Marr, when they sing, they're constantly releasing viral particles into the air, probably like this. And they'll drift around the room, they won't just be dumped on the floor. And as the singing continues, there will be more and more of them in the room. And you can see them drifting and reaching people nearby. And they were there for two and a half hours. And you can imagine that after that amount of time, the other people had already inhaled enough of them to get sick. Especially if the ventilation and air conditioning system was turned off at night.

The heating, ventilation and air conditioning (HVAC) system is the heart and lungs''any building. The researchers hypothesized that the thermostat likely turned off the HVAC system because the choir members were generating enough heat with their bodies. It is highly likely that the room had very poor ventilation, as our data suggests the system was not working.

Then Professor Marr increased air circulation to show us how better air circulation could help remove aerosols and slow the spread of the virus. The analysis led to one of the most significant articles on the importance of ventilation published during the pandemic. Then, last year, a study in Italy went further. It showed that using school fans and ventilation ducts to mechanically replace indoor air with outdoor air five times per hour''reduces the risk of COVID-19 infection by at least 80 percent. However, in the U.S., until May of this year, the Centers for Disease Control and Prevention recommended only the frequency of air exchange.

If you look at the way we design and operate buildings like offices, schools, local coffee shops, you could say we don't design them with health in mind.

We only have minimum standards. In schools, the minimum air exchange rate by design is about three air exchanges per hour. But we need a minimum of four to six. If we had these indoor air quality goals before the pandemic, do you think the pandemic would have developed differently? We would still have experienced a spread. It's not a thing that will end the pandemic. But''spread would be much less, and there would be far fewer such super-spreading events. Think about the early days of the pandemic, the 'flatten the curve', the 'stay home'. Why wasn't "improving indoor air quality" part of "flatten the curve"?

Buildings are Joe Allen's business.

He is the founder of Harvard University's Healthy Buildings Program and has been diagnosing problems in air quality systems and developing solutions for clients including CBS's parent company, Paramount, and commercial properties like Beacon Capital Partners, with buildings like this one in downtown Boston. He has also consulted''Amazon before the opening of these new 22-story towers last May in Arlington, Virginia, where he gave us a tour.

What does a modern building look like in terms of ventilation? "

There are a lot of elements you can see in this building. You have an outside air system that delivers air above the minimum requirements. Then it goes through two MERV-13 rated filter systems, and you have very well filtered air. MERV stands for minimum filtration efficiency. A rating of 13 means it captures up to 90 percent of the suspended particles in the air... depending on their size. is the first line of defense against not only COVID, but also other respiratory viruses such as influenza and RSV. This whole process determines,''Whether you're going to be healthy or sick inside the building, what happens in that space.

The top floor of Amazon's new office is home to motors, pipes and ductwork... part of a $2.5 million HVAC system that starts with huge vents and dampers on the roof. Prof. Allen: This is where the entire ventilation system is located. This is where the air enters the building, is filtered, cooled and then delivered. This determines how much air actually reaches the workplaces and how clean that air is. Downstairs, each floor has a sensor that tells the building's engineers the quality of the indoor air, such as the level of carbon dioxide, known as CO2. We exhale carbon dioxide. The less carbon dioxide, the better the ventilation.''Very simple. A high carbon dioxide level means you're not getting enough fresh air from this system we've just looked at. If the level is low, everything is fine. We also measure particulates. This tells us the condition of the outside atmosphere, such as outdoor air pollution. The whole system can be monitored and controlled from the basement. Remember what we said about carbon dioxide being an indicator for ventilation? I see that in this building they are all below 800 parts per million. Is that good? That's great. And very important: If a lot of people came in, the CO2 levels would go up, this system would notice that. The dampers would open and bring in a lot more fresh air.

Katie Hughes, director of health and''safety at Amazon, points to waves of smoke from wildfires that rolled in from the north from Canada as the ultimate test of the indoor air quality system. So Katie Hughes: Recently, Washington state and Virginia were virtually engulfed in smoke that came down from the north from Canada. What happened in the building? You would expect that the indoor air quality was not very good. Our buildings were performing very well. Hughes says Amazon is updating many of its ventilation systems, including warehouses. In a recent survey of facility managers in the U.S. and Canada, about two-thirds have improved their MERV filters and increased air exchange rates since March 2020. JPMorgan Chase in New York