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COVID-19 can be spread by building ventilation, say Canadian researchers working on an HVAC fix – St. Thomas Times-Journal

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A group of Alberta researchers are working on ways that buildings could change their HVAC set-ups to curb the risk of infection

An African restaurant is closed off along with other businesses in Guangzhou’s Sanyuanli area, where a neighborhood is in lockdown after several people tested positive for the novel coronavirus disease (COVID-19), in Guangdong province, China April 13, 2020.

REUTERS/David Kirton

The outbreak of COVID-19 at a restaurant in the southern Chinese city of Guangzhou was a puzzle.

The suspected index patient was a visitor from the coronavirus’s epicentre in Wuhan. But the eight other customers who later tested positive were not sitting close enough for droplet transmission, and most of the patrons and staff avoided infection altogether.

A team of local scientists eventually came to an eye-opening conclusion about the episode: tiny particles of virus had hitched a ride on currents created by the eatery’s air-conditioning.

That runs counter to the prevailing view that the novel coronavirus is transmitted only by heavier “droplets.” But for a group of civil engineers at the University of Alberta, the finding was no surprise. In their world, they say, it’s well known that building ventilation systems are efficient disseminators of viruses and other pathogens, and they believe the COVID-19 bug is no exception.

Aided by a $440,000 federal-government grant, they’re now working on ways that buildings could change their HVAC set-ups to curb the risk of infection, what the researchers call a “non-pharmaceutical” intervention against the disease.

We want to save lives, let’s cut right to the chase

“We want to save lives, let’s cut right to the chase,” said Prof. Brian Fleck, part of the project. “There are so many, many, many buildings … This affects absolutely everybody. Billions of people. If we are able to cut down the transmission rate by a per cent, that’s a lot of people.”

The engineers’ belief in the importance of building ventilation as a transmitter of the COVID-19 virus is not universally held.

The World Health Organization and other public-health bodies, citing the science to date, say the pathogen is spread almost entirely by droplets, heavier particles emitted mostly when infected people cough or sneeze, and which fall down within a short distance. Hence the two-metre rule for social distancing, and the emphasis on washing hands after touching surfaces where virus may have alighted.

“The HVAC systems in most non-medical buildings play only a small role in infectious disease transmission, including COVID-19,” argued the American Society of Heating, Refrigerating, and Air-Conditioning Engineers last month.

It’s just smaller and lighter aerosol particles that can spread through a ventilation system and “the truth is that we still don’t really know if the (COVID-19) virus can be spread by aerosols,” said Matthew Miller, a virus expert at McMaster University in Hamilton.

But Chinese and Australian air-quality experts, citing in part the experience with SARS, another coronavirus, argued in a paper earlier this month that as droplets from an infected person start to evaporate, the resulting smaller particles can indeed become airborne.

They point to evidence that passengers confined to their cabins on cruise ships like the Diamond Princess may have been infected through the vessels’ air ducts.

“It is highly likely that the SARS-CoV-2 virus also spreads by air,” they conclude, urging “all possible” action in response, including modifications to ventilation systems. “We predict that … failure to immediately recognize and acknowledge the importance of airborne transmission and to take adequate actions against it will result in additional cases.”

Then there was the Guangzhou restaurant case, detailed in a U.S. Centers for Disease Control online journal recently. Researchers concluded flow from an air conditioner moved over three tables, carrying virus from the infected patron at the middle one to the far table, then back to the diners closest to the air conditioner.

Even if it turned out SARS-CoV-2 does not spread that way, influenza viruses can, and the University of Alberta research would be valuable for that reason alone, said Miller.

Heating, ventilation and air conditioning (HVAC) engineers have long known that tiny particles of pathogen travel in the air that is circulated, heated and cooled in modern buildings, said Fleck. He pointed to Legionnaires disease, a bacterial pneumonia first traced to a hotel’s air-conditioning system.

The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office

“This has been on people’s radar for quite a while,” he said. “Somebody on a different floor sneezes …The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office.”

There are various ways that the risk can be lessened, including use of filters that catch a greater number of those particles, and drawing more fresh air into a system. It also is likely that higher levels of humidity – a factor that only some Canadian buildings can adjust – will help kill off the virus, said Fleck.

But each of those changes carries a cost. Adding more fresh air can require additional heat or air conditioning. Heavier filters means more energy is needed to push the air through them. And more humidity can lead to mould, he noted.

“This will make for difficult decision making.”

Funded by the Canadian Institute for Health Research, the University of Alberta project is led by engineering professor Lexuan Zhong and also involves pediatrics professor Lisa Hartling. It consists of three phases: systematically reviewing literature on air circulation and viruses, determining what strategies would be effective and then carrying out a detailed audit of all the buildings on the Edmonton campus to create a real-world model of what should be done.

The team hopes to have solid results by the summer of 2021, said Fleck.

(Modified 12:40 April 26 to add comments by Matthew Miller.)

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Tesla's Musk earns $770M in stock options, company confirms – OttawaMatters.com

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DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

The Associated Press

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Tesla's Musk earns $770M in stock options, company confirms – GuelphToday

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DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

The Associated Press

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Tesla's Musk earns $770M in stock options, company confirms – Times Colonist

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DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

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Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

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