“How much of the air you're breathing is air someone else exhaled? And in the midst of a pandemic caused by an airborne virus, where are the riskiest places to be? In the first in a series of five stories Farah Hancock reports on hot spots of hazardous air.”
“Shuffling my way onto the bus I had no idea it might be the most dangerous thing I would do all day…
From a level of 516 parts per million at the bus stop, it took only 20 minutes for CO2 inside the bus to peak at a whopping 5737ppm.”
From a level of 516 parts per million at the bus stop, it took only 20 minutes for CO2 inside the bus to peak at a whopping 5737ppm.”
“CO2 levels can be used as an indicator of the risk of catching Covid-19; we breathe in air & release CO2 when we exhale. Covid-19 is spread via aerosol particles breathed, coughed or sneezed out by infected people. These can drift several metres and linger in the air for hours.”
“At 5737ppm, the equivalent of one in every seven breaths I took on the bus was air other people had breathed out. I texted a friend: "OMG, the readings are so high I may as well let the other passengers lick my face!"”
“”You can think of it as spit particles, tiny spit particles are what you are breathing in," says University of Auckland aerosol chemist Dr Joel Rindelaub. "It's breath backwash that gets people infected."”
“…CO2 outdoors is about 420ppm. Rindelaub says a good indoor reading would be anything below 800ppm… When readings get above 1000ppm there could be a high risk of Covid-19 transmission if someone in the space is infected.
"If you're above 2000, then that's a huge 🚩."“
"If you're above 2000, then that's a huge 🚩."“
“The CO2 monitor smuggled into one school on three different days gave a top reading of 1373ppm.
"For a school learning environment, I would say that is too high…
At 1373ppm, one in every 33 breaths the class of 30 children were inhaling would be breath backwash.”
"For a school learning environment, I would say that is too high…
At 1373ppm, one in every 33 breaths the class of 30 children were inhaling would be breath backwash.”
“Every office is different, & every seat can be… too. Readings taken… show desks by open doors have lower readings than desks tucked into corners.
Readings ranged from 587ppm to 1167ppm…
3 people in a meeting room for 1 hr saw the level rise from around 700 to 1000ppm”
Readings ranged from 587ppm to 1167ppm…
3 people in a meeting room for 1 hr saw the level rise from around 700 to 1000ppm”
“Readings RNZ recorded in bars were lower than in public transport but this doesn't automatically equate to a lower risk, says Rindelaub.”
“ "When you're at a bar or restaurant, you're socialising, you're going to be talking a lot. When you're talking, you're actually expelling way more particles, thousands of more particles, than just breathing regularly."”
“…no masks means there's an increased risk of catching an airborne disease if someone in the same space…is sick.
The highest reading recorded was 2624ppm, from a bar with only 22 people... The equivalent of every 1 in 17 breaths here is air that other people have exhaled.”
The highest reading recorded was 2624ppm, from a bar with only 22 people... The equivalent of every 1 in 17 breaths here is air that other people have exhaled.”
“Readings taken in exercise venues ranged from 630 to 4228ppm. Gyms generally don't require mask wearing.
The highest reading of 4288ppm was taken in a yoga class with 30 people in the room. This means the equivalent of one in every 10 breaths taken was backwash.”
The highest reading of 4288ppm was taken in a yoga class with 30 people in the room. This means the equivalent of one in every 10 breaths taken was backwash.”
“ "Cars are gross," says Rindelaub. "You're in a tiny area, there's no ventilation if the windows are up. So these CO2 ratings and these particles are going to get super high super quick, especially if you have more than one or two people in the car."”
“The highest reading of 5040ppm was taken in an Uber with a driver and one passenger. This equated to one in every eight breaths being backwash.
Opening a window, even just a small amount, can help, says Rindelaub.”
Opening a window, even just a small amount, can help, says Rindelaub.”
“Even in your own car it's worth thinking about risk. Parents ferrying multiple children to Saturday sports for example, should take infection into account…
… I would definitely have people wear masks if you were bringing in multiple people from different families into one tiny, tiny, enclosed place because that would be high risk."”
“Rindelaub says if he was getting on a bus he would be opting for the best possible mask, such as an N95, and wearing it correctly…
…Wearing a mask beneath your nose is "pretty silly," he says.
"We have decent evidence that Covid actually attacks you in your nasal passages. That's where Covid starts to infect you. So if you don't have it over your nose, you're not really helping anybody out."”
"We have decent evidence that Covid actually attacks you in your nasal passages. That's where Covid starts to infect you. So if you don't have it over your nose, you're not really helping anybody out."”
“"We spend 90% of our time indoors whether it's at the office, at the home, in a car or transport between the two. It's really important to have fresh air all the time."…
…He worries even though we now know the dangers of letting breath particles linger inside, not enough attention is given to improving ventilation.“
“Dr Julie Bennett is a Sr research fellow in the University of Otago's Dept of PH.
"I would like to see a gov department or org take responsibility for indoor air quality…
Bennett says an immediate fix is putting prominent carbon dioxide monitors in public spaces.“
"I would like to see a gov department or org take responsibility for indoor air quality…
Bennett says an immediate fix is putting prominent carbon dioxide monitors in public spaces.“
“She says New Zealand is behind countries such as France, which has been measuring indoor air quality for several years…”
“But our country is not alone in overlooking indoor air quality. Ontario Society of Professional Engineers indoor air quality group chairperson @joeyfox85 uses Twitter to share the importance of ventilation in fighting Covid-19.“
“…making buildings safe, improving ventilation & filtration everywhere, that's something that we can do," he says.”
“He adds that it shouldn't be up to individuals to suffer the burden of filtering every particle of air they breathe so they're less likely to get sick.
"It's an obligation on society [and] on the building to provide safe spaces for people."
"It's an obligation on society [and] on the building to provide safe spaces for people."
Consequences of #BreathBackwash
H/T @DavidSteadson
Re/infection prevention of #SARS2 is the job of Governments and PH on a population level
We have the tools
It’s time to use them
#FASSST
H/T @DavidSteadson
https://twitter.com/DavidSteadson/status/1546308765171224576?s=20&t=-UKnsAai8vhbKUP4-Emnmg
Re/infection prevention of #SARS2 is the job of Governments and PH on a population level
We have the tools
It’s time to use them
#FASSST
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