SARS-CoV-2 concentrations and virus-laden aerosol distributions in outdoor air(sciencedirect.com)
sciencedirect.com
SARS-CoV-2 concentrations and virus-laden aerosol distributions in outdoor air
https://www.sciencedirect.com/science/article/pii/S0160412020322108?via%3Dihub
184 comments
I've been stopped and scolded by "concerned citizens" before (even recently) for going on runs/hikes without wearing a mask... I tried to explain how outdoors masks are only really necessary where social distancing isn't possible and crowd density is high but they seemed to think I was just an anti-masker. At least now I can point to an actual study, for whatever good it will do...
These people most likely did not arrive to their conclusions by reading studies themselves, and likely aren't going to be persuaded differently by one.
Most people gain their understandings of best public health practices from the statements of authorities they trust. Unfortunately, a lot of nuance is lost when people get their information second, third, or fourth-hand.
Most people gain their understandings of best public health practices from the statements of authorities they trust. Unfortunately, a lot of nuance is lost when people get their information second, third, or fourth-hand.
Judging by the replies a lot of people agree with those concerned citizens. I hope that the majority are terrified by this. It is one thing to recommend masks for legit health concerns, but it's a very slippery slope that we've already gone far down towards them becoming a religious/ political talisman that signified whether you are willing to shut up and agree with your leaders, or be an "anti-masker". We need to be more outspoken about all these baby steps toward complete submission to superstition.
The trouble is that there are actual "anti-masker" that don't wear masks in crowded areas and are actually responsible for the deaths of thousands of people.
>actually responsible for the deaths of thousands of people
No proof
No proof
Wow, so that’s where we are now: following sensible public health advice by wearing a little piece of cloth on your face = baby steps toward complete submission to superstition.
If anything, I hope this pandemic helps to normalize mask wearing. People’s mouths and noses are disgusting, and a common source of non-lethal aerosolized diseases. Prior to COVID people used to sneeze and cough all over everything in public without even thinking about it, and I used to get colds all the time. Haven’t even got the sniffles since masks became mandated. Sure, sample size of one, and all. I’ll probably continue to wear a mask in public after this all goes away. When I see an unmasked face now, I mentally think “disease carrier” and avoid. We really could use this small norm-change society-wide.
If anything, I hope this pandemic helps to normalize mask wearing. People’s mouths and noses are disgusting, and a common source of non-lethal aerosolized diseases. Prior to COVID people used to sneeze and cough all over everything in public without even thinking about it, and I used to get colds all the time. Haven’t even got the sniffles since masks became mandated. Sure, sample size of one, and all. I’ll probably continue to wear a mask in public after this all goes away. When I see an unmasked face now, I mentally think “disease carrier” and avoid. We really could use this small norm-change society-wide.
> masks are only really necessary where social distancing isn't possible
All well and good as long as everyone buys into social distancing. Unfortunately plenty of people believe in neither masks nor social distancing, so you can't trust that people (strangers in the same vicinity) will stay 6ft apart.
All well and good as long as everyone buys into social distancing. Unfortunately plenty of people believe in neither masks nor social distancing, so you can't trust that people (strangers in the same vicinity) will stay 6ft apart.
There is no magic "6ft apart". It's just the maximum that seemed reasonable to demand. It's about the width of a supermarket aisle or a typical business hallway. Metric countries surely don't use that distance. Nothing is said about length of exposure or ventilation quality either.
There is no such thing as a perfectly safe distance but there is a "you're really risking common spread in most situations if less than" and that's where the 6 feet/ 2 meter number somes from and why it's relevant not because the virus counts out 6 feet and drops dead. I don't think anyone here is claiming that by referencing it either and you always want more distance if it's reasonably possible.
I believe there are several qualifiers on that number, though. For example, the CDC "close contact" guidelines say that a close contact is "someone who was within 6 feet of an infected person for a cumulative total of 15 minutes or more over a 24-hour period".
Passing someone on a sidewalk means you're within 6 feet for maybe 5 seconds, which would constitude about 0.5% of such a "close contact" exposure.
They also say that several factors with insufficient data mean that it's unclear how things like ventilation, indoor vs outdoor, mask vs no mask, etc, affect the exposure assessment.
https://www.cdc.gov/coronavirus/2019-ncov/php/contact-tracin...
Passing someone on a sidewalk means you're within 6 feet for maybe 5 seconds, which would constitude about 0.5% of such a "close contact" exposure.
They also say that several factors with insufficient data mean that it's unclear how things like ventilation, indoor vs outdoor, mask vs no mask, etc, affect the exposure assessment.
https://www.cdc.gov/coronavirus/2019-ncov/php/contact-tracin...
The Netherlands and maybe other European countries use 1.5 meters (~ 5 feet) as their guideline.
Metric countries use 2 meters, and it's determined by how far droplets fly when you talk/cough/sneeze. If covid were only transmitted via droplets, 6 feet/2 meters of distance would be enough. Alas.
Indeed, I've seen anything between 1-2 meters and a small moose (SI unit of distance in the local zoo)..
I saw a video where a person, walking alone on an apparently empty sidewalk, is not scolded but harassed for not wearing a mask (there is a mask, just not worn). The harasser was the one proudly filming their heroic act.
(Addendum: there’s the obvious question, why not just wear a mask 100% of the time? There are no downsides, right? — There can be. Perhaps my mask had been in use for a while, I suspect it’s gotten dirty enough to be a potential health hazard, but I don’t have another mask to replace it? I’d still use it if people are around, but would try to reduce my exposure to it otherwise. Maybe I have asthma or some type of breathing difficulty, and wearing a mask makes it worse? I think those two are probably among the most common reasons.)
(Addendum: there’s the obvious question, why not just wear a mask 100% of the time? There are no downsides, right? — There can be. Perhaps my mask had been in use for a while, I suspect it’s gotten dirty enough to be a potential health hazard, but I don’t have another mask to replace it? I’d still use it if people are around, but would try to reduce my exposure to it otherwise. Maybe I have asthma or some type of breathing difficulty, and wearing a mask makes it worse? I think those two are probably among the most common reasons.)
WHO explicitly recommends against wearing masks while exercising: https://www.who.int/emergencies/diseases/novel-coronavirus-2...
>FACT: People should NOT wear masks while exercising
>People should NOT wear masks when exercising, as masks may reduce the ability to breathe comfortably.
>Sweat can make the mask become wet more quickly which makes it difficult to breathe and promotes the growth of microorganisms. The important preventive measure during exercise is to maintain physical distance of at least one meter from others.
>FACT: People should NOT wear masks while exercising
>People should NOT wear masks when exercising, as masks may reduce the ability to breathe comfortably.
>Sweat can make the mask become wet more quickly which makes it difficult to breathe and promotes the growth of microorganisms. The important preventive measure during exercise is to maintain physical distance of at least one meter from others.
> The harasser was the one proudly filming their heroic act.
This behavior seems to be part of Call Out Culture.
https://www.youtube.com/watch?v=2e9VYf9FKHo
This behavior seems to be part of Call Out Culture.
https://www.youtube.com/watch?v=2e9VYf9FKHo
For anyone interested in 'cancel culture' sans the reactionary right-wing propaganda: https://youtube.com/watch?v=OjMPJVmXxV8
What is "reactionary right-wing propaganda" about Jonathan Haidt [1]? That's a completely unfounded assertion.
[1]: https://en.wikipedia.org/wiki/Jonathan_Haidt
[1]: https://en.wikipedia.org/wiki/Jonathan_Haidt
That's why "sans" was there.
Perhaps English is your second language (given your German username?) — "sans" means without. Thus the comment was implying that the ContraPoints video was "without" the implied "right-wing propaganda" in the Jonathan Haidt / Joe Rogan video.
Indeed its my second language, but I did get the meaning of sans right. Unfortunately I got mixed up with the two youtube links instead :)
This seems like it risks having an opposite effect.
How about the downside of normalizing wearing a mask? These are not normal times and this is not the new normal; I want everyone to wear a mask because it must be done not because we should permanently condition ourselves that this is how we now live.
I think the downside of not wearing a mask is, in fact, normalising not wearing a mask in the eyes of people who do not take into account that it’s not worn for a reason and because there is no one near me. Thus I try to put mask on when I see someone on the street even if they are far away.
I think not wearing masks again will be easy to normalise. For example, Hong Kong got hit by the first SARS and everyone wore a mask for a time, and then when it was over all was back to normal and masks quickly became rare.
I think not wearing masks again will be easy to normalise. For example, Hong Kong got hit by the first SARS and everyone wore a mask for a time, and then when it was over all was back to normal and masks quickly became rare.
I hope you are right, but I'm not convinced. Covid isn't just going to go away like switching off a light switch. A good number of people have gone way off the deep end with regard to "being safe". I'm not sure they will be able to reason about when the risk is low enough to be able to stop wearing a mask.
I believe once vaccines and better treatment are generally available and proven effective, it will be a cue to very quickly abandon excess caution for most people, even those who have gone to the extreme.
Larger countries (including the US) that are more sparsely populated and tend to rely on central messaging from authorities less will probably have areas that are slower at adopting new measures (or lack thereof), which may be frustrating, but I imagine large cities will be able to react promptly.
Larger countries (including the US) that are more sparsely populated and tend to rely on central messaging from authorities less will probably have areas that are slower at adopting new measures (or lack thereof), which may be frustrating, but I imagine large cities will be able to react promptly.
Some countries are now at nearly zero cases.
We should absolutely be normalizing wearing masks in public. In many parts of the civilized world (where, by miraculous chance, they've also handled Covid reasonably responsibly) people who were sick in public (or even just wanted to avoid putting on makeup) habitually wore masks pre-covid to avoid infecting others. I'd be willing to assert that it's exactly that habit (and a related set of hygiene conditions, in addition to an already-present infrastructure for home PPE) that helped them return to living much more normal lives through this pandemic.
I wrote in another comment up thread, one great result of this pandemic is that it could help to normalize mask wearing in general. People’s mouths and noses are disgusting, and a common source of non-lethal aerosolized diseases. There is really little downside to wearing a mask while around people and healthy upside.
The societal norm/expectation that we wear clothing in public is no big deal. Why can’t we have a similar mask-wearing norm? I don’t see many anti-clothers protesting city hall over their right to go naked.
The societal norm/expectation that we wear clothing in public is no big deal. Why can’t we have a similar mask-wearing norm? I don’t see many anti-clothers protesting city hall over their right to go naked.
One side-effect I am thinking of is that if our immune systems receive less challenge they could weaken over long term (maybe generations).
Hopefully that’s not how things work, or the effect has no practical significance.
Second best option, we’ll find a way to compensate for that.
Else, maybe we shouldn’t normalise masks to such a degree except for periods when it’s necessary.
Another side-effect is that masks should be replaced regularly, so everyone wearing masks at all times would mean a lot of waste (hopefully bio-degradable).
Hopefully that’s not how things work, or the effect has no practical significance.
Second best option, we’ll find a way to compensate for that.
Else, maybe we shouldn’t normalise masks to such a degree except for periods when it’s necessary.
Another side-effect is that masks should be replaced regularly, so everyone wearing masks at all times would mean a lot of waste (hopefully bio-degradable).
You know, I'd happily normalise "wear a mask if you want, especially if you're coughing". But without peer pressure in either direction once we're back to low stakes.
This was pretty much my experience in pre-COVID Hong Kong (which got hit by the first SARS earlier).
>I tried to explain how outdoors masks are only really necessary where social distancing isn't possible
How close did these people get to you when trying to express their concern?
How close did these people get to you when trying to express their concern?
Actually, maybe they've read studies like this one: https://medium.com/@jurgenthoelen/belgian-dutch-study-why-in...
This isn't a study, it's a PR piece, and it was debunked months ago. CFD is a poor tool for this kind of analysis:
https://www.bicycling.com/news/a32097735/coronavirus-viral-s...
https://www.bicycling.com/news/a32097735/coronavirus-viral-s...
Yeah, I should trust Byclicing.com as the source of science. Okay, maybe it's a whitepaper, but much of our defenses are based on realistic model. I'd rather trust a model than a sports magazine promoting bicycling.
Typically, the best practice is to wait for results from multiple studies, and have them confirm the same conclusion. Otherwise, there is a risk it being a fluke or having some other bias in the data (e.g. environmental humidity, etc.)
Personally these days, for outdoors, I use the following algorithm:
1. Over 6 feet away from people: Wear a mask below the nose (so I can have it ready for state #2 below, when needed).
2. Under 6 feet away from someone (even if just passing them by): Wear a mask properly (i.e. over the mouth AND nose).
Edit: Formatting.
Personally these days, for outdoors, I use the following algorithm:
1. Over 6 feet away from people: Wear a mask below the nose (so I can have it ready for state #2 below, when needed).
2. Under 6 feet away from someone (even if just passing them by): Wear a mask properly (i.e. over the mouth AND nose).
Edit: Formatting.
What is the point of wearing the mask below the nose? I find that the only reason to not wear a mask is discomfort from heat and sweat. Wearing a mask, but wrong, doesn't help that.
As for my personal set of rules: if I can distance 12 feet I don't wear one. If I am frequently passing people (on sidewalks or trails) I keep it on. If it is fairly empty and I pass someone every once in a while, I keep the mask in my hand and breath through it when I pass someone.
As for my personal set of rules: if I can distance 12 feet I don't wear one. If I am frequently passing people (on sidewalks or trails) I keep it on. If it is fairly empty and I pass someone every once in a while, I keep the mask in my hand and breath through it when I pass someone.
Why wear mask below nose when I am far away from everyone?
Why not just take it off? I want to have easy access to move it up when needed. I am typically just walking and the weather is cool these days, so I do not experience sweating. Also since the hot air is not exhaled directly into the mask, it prevents/slows down the heating of the mask.
Why not wear it fully? I find it easier sometimes to breathe without a mask. So, when it is safe to do so, I lower it.
Why not just take it off? I want to have easy access to move it up when needed. I am typically just walking and the weather is cool these days, so I do not experience sweating. Also since the hot air is not exhaled directly into the mask, it prevents/slows down the heating of the mask.
Why not wear it fully? I find it easier sometimes to breathe without a mask. So, when it is safe to do so, I lower it.
It doesn't matter what your understanding of the science is. By passing other people without having a mask you pull up, you're imposing your estimates of safety on others, who may wish to avoid having to pass people who aren't wearing masks, even outdoors.
That's extremely obnoxious behavior, even though you're likely right on the low risks of transmission in sparse outdoor settings.
That's extremely obnoxious behavior, even though you're likely right on the low risks of transmission in sparse outdoor settings.
> you're imposing your estimates of safety on others, who may wish to avoid having to pass people who aren't wearing masks, even outdoors
This is precisely the insufferable safety-ism that characterizes the 21st century.
If you feel particularly at risk in the case of infection, and you'd wish to avoid infection - stay inside and isolate.
Isn't completely fair to say that the frail among us are imposing on everyone else outdoors keeping healthy and not depressed by exercising, etc?
If you "may wish to avoid having to pass people who aren't wearing masks": stay home!
This is precisely the insufferable safety-ism that characterizes the 21st century.
If you feel particularly at risk in the case of infection, and you'd wish to avoid infection - stay inside and isolate.
Isn't completely fair to say that the frail among us are imposing on everyone else outdoors keeping healthy and not depressed by exercising, etc?
If you "may wish to avoid having to pass people who aren't wearing masks": stay home!
I agree up to a point. Though I'd observe that outdoor dining with tables separated by 6 feet with people sitting for an extended period of time without masks is happening widely in many places. So the idea that outdoor dining is safe but walking past other people on a trail is not is pretty inconsistent.
I didn't see the commenter arguing on behalf of outdoor dining, so that's a bit of a straw man argument. Additionally, there's a difference between people opting to participate in mutually risky behavior (eating maskless in a restaurant during a pandemic) vs. imposing their risky behavior on people not participating (maskless jogging in shared spaces where others are acting responsibly by wearing masks).
I see it all the time and I personally think it's incredibly irresponsible. But hey - we have to keep the restaurants in business...at the expense of prolonging the pandemic.
Here's an idea, you can already keep them in business, order delivery w/ no-contact delivery.
Yes, life is certainly inconvenienced, but what's the alternative? Is going out to dinner worth directly or indirectly killing another human being over?
Here's an idea, you can already keep them in business, order delivery w/ no-contact delivery.
Yes, life is certainly inconvenienced, but what's the alternative? Is going out to dinner worth directly or indirectly killing another human being over?
> But hey - we have to keep the restaurants in business...at the expense of prolonging the pandemic.
Could you elaborate on what "prolong" means? Say we shut down the entire country for 4 weeks and get the virus under control. Is the pandemic now "over" (i.e. no longer prolonged) and we can reopen restaurants again at full capacity and just treat individual outbreaks? Or is it going to be cyclical where cases start rising again and the governors start cracking down again ad infinitum? For island nations that can control who goes in and out it's one thing, but it's going to be very hard for USA or EU which has open borders between states to control spread of contagious disease.
Could you elaborate on what "prolong" means? Say we shut down the entire country for 4 weeks and get the virus under control. Is the pandemic now "over" (i.e. no longer prolonged) and we can reopen restaurants again at full capacity and just treat individual outbreaks? Or is it going to be cyclical where cases start rising again and the governors start cracking down again ad infinitum? For island nations that can control who goes in and out it's one thing, but it's going to be very hard for USA or EU which has open borders between states to control spread of contagious disease.
Or the people who don't want to eat at restaurants and walk past people on a trail should just stay home. I certainly haven't seen the evidence that these are risky activities. You can't eliminate any risk without literally putting everyone in quarantine by themselves.
> Or the people who don't want to eat at restaurants and walk past people on a trail should just stay home.
Spoken like a true narcisist. This is the exact behavior that produces the continued rise in cases across the country.
> I certainly haven't seen the evidence that these are risky activities.
Well, I'm glad you've appointed yourself epidemiologist-in-chief.
> You can't eliminate any risk without literally putting everyone in quarantine by themselves.
No, you can eliminate much of the risk by isolating with your household, occupation permitting.
A little compassion for people would go a long way.
Spoken like a true narcisist. This is the exact behavior that produces the continued rise in cases across the country.
> I certainly haven't seen the evidence that these are risky activities.
Well, I'm glad you've appointed yourself epidemiologist-in-chief.
> You can't eliminate any risk without literally putting everyone in quarantine by themselves.
No, you can eliminate much of the risk by isolating with your household, occupation permitting.
A little compassion for people would go a long way.
I am following the rules in my very blue state. ADDED: (And, in fact, going beyond them as I'll pull up a neck gaiter on a trail if I'm approaching although distanced from people wearing masks--to increase their comfort level.) I also mostly avoid busier recreation areas and have only done outdoor dining a couple of times. But, yes, I think that so long as people are following what seem to be fairly conservative government guidelines, those who don't agree with the government's assessment should stay home rather than expect people en masse to behave in ways that go beyond state mandates and recommendations.
When someone drives a car, they impose their estimates of safety on pedestrians.
Is that obnoxious?
Is that obnoxious?
In many cases yes. E.g. drivers who use residential streets as through streets are certainly obnoxious.
I don't think you can accurately make simple analogies like this. What is discussed here is more like what speed you should be going if you driving path intersects a pedestrian's path (possibly in a crosswalk). Then there is a difference between someone stopping and seeing the pedestrian is very far away and turning right vs. someone doing a 45 mph and driving within a few feet of a pedestrian. Different drivers and pedestrians will have different expectations.
No, it's all degrees of risk.
The only accurate way is to quantify the risk, rather than blindly assert "extremely obnoxious behavior".
The only accurate way is to quantify the risk, rather than blindly assert "extremely obnoxious behavior".
If they don't want to pass people that aren't wearing masks, shouldn't they stay home?
[deleted]
No they should not, because to wear the mask all the time is much easier than to stay home all the time. Unless you are some entitled narcissist or something.
I support wearing masks, but have seen the science on outdoor transmission and don't wear one on the very empty trails I hike on. However, I saw a big flaw in your logic:
So it's "extremely obnoxious" when the OP "imposes their estimates of safety on others", and the correct response is for the OP to allow the misinformed estimates of safety of the others to require a mask be pulled up.
Why stop there? Some people think that a neck gaiter or cloth mask isn't enough. Why not wear an N95 outdoors since some people "wish to avoid having to pass people who aren't wearing [N95] masks, even outdoors".
Who gets to draw the line between obeying the science vs obeying the theatrical needs of the anxious ignoramuses? Surface transmission isn't a factor with this virus, and yet I know a few folks who still insist on disinfecting every box they come in contact with. They are welcome to do that, but it's certainly not following the science. Am I to cater to these people to?
So it's "extremely obnoxious" when the OP "imposes their estimates of safety on others", and the correct response is for the OP to allow the misinformed estimates of safety of the others to require a mask be pulled up.
Why stop there? Some people think that a neck gaiter or cloth mask isn't enough. Why not wear an N95 outdoors since some people "wish to avoid having to pass people who aren't wearing [N95] masks, even outdoors".
Who gets to draw the line between obeying the science vs obeying the theatrical needs of the anxious ignoramuses? Surface transmission isn't a factor with this virus, and yet I know a few folks who still insist on disinfecting every box they come in contact with. They are welcome to do that, but it's certainly not following the science. Am I to cater to these people to?
> Who gets to draw the line between obeying the science...
The science should! Here's what the CDC says for high intensity activities:
"Masks should be used in public settings, but if you are unable to wear a mask because of difficulty breathing during high intensity activities, choose a location with greater ventilation and air exchange (for instance, outdoors versus indoors) and where you can keep at least 6 feet from others during the activity."
The trails and parks around here (North Carolina) have enough traffic and people who believe "I do what I want" that I don't feel comfortable visiting these places period.
The science should! Here's what the CDC says for high intensity activities:
"Masks should be used in public settings, but if you are unable to wear a mask because of difficulty breathing during high intensity activities, choose a location with greater ventilation and air exchange (for instance, outdoors versus indoors) and where you can keep at least 6 feet from others during the activity."
The trails and parks around here (North Carolina) have enough traffic and people who believe "I do what I want" that I don't feel comfortable visiting these places period.
I don’t know, I also run outdoors without a mask. If I see someone I cross the road and make sure I stay at least 5 m/yards away from anyone.
Very hard to do in denser cities with narrow sidewalks and heavy foot traffic, or around park paths
Yeah that's very reasonable behavior.
I doubt the person upthread is doing this though, given that he seems to be going close enough to people that they can stop and scold him.
I doubt the person upthread is doing this though, given that he seems to be going close enough to people that they can stop and scold him.
Yeah, if someone tries to speak to me I run away for sure if I don't have a mask. Not going to have a discussion with strangers these days unless it is on the internet :-)
"By passing other people without having a mask you pull up, you're imposing your estimates of safety on others, who may wish to avoid having to pass people who aren't wearing masks, even outdoors. That's extremely obnoxious behavior, even though you're likely right on the low risks of transmission in sparse outdoor settings."
Wait wait wait...why should everyone be required to cater to the most paranoid people in the world, or be considered "obnoxious"? Where does this end? If I walk down the street, and someone twenty feet away from me scowls at me because I'm not wearing a mask, that's objectively their problem, not mine.
If you're so scared that you can't stand the idea of someone else being outside without obeying your rules, then perhaps you should reconsider being outside in the first place.
Wait wait wait...why should everyone be required to cater to the most paranoid people in the world, or be considered "obnoxious"? Where does this end? If I walk down the street, and someone twenty feet away from me scowls at me because I'm not wearing a mask, that's objectively their problem, not mine.
If you're so scared that you can't stand the idea of someone else being outside without obeying your rules, then perhaps you should reconsider being outside in the first place.
If you're annoyed by getting scolded for not wearing a mask, maybe you shouldn't be outside in the first place.
I'm not annoyed. I recognize that some people have personal problems that I cannot change.
I NEVER go within 10 feet of people on a trail without a mask. The rule is 6 feet, and I add the extra few feet to remove ambiguity. When I go to certain trails in the Boulder, CO area, there are many "mask nazis" who clearly are extremely paranoid, and on a power trip. They will absolutely not hesitate to scold and holler despite me walking off the trail and not going anywhere near them. Your assumption that everyone is rational and people getting scolded is a sign of their guilt is just wrong.
For anyone that lives in the area, the worst are the Nederland residents. Territorial assholes when there isn't a pandemic, and now they feel empowered to really let you have it. Going 10 miles south to trails in Jefferson County, and as long as you stay 6 feet or more, people smile and tell you to have a nice hike.
For anyone that lives in the area, the worst are the Nederland residents. Territorial assholes when there isn't a pandemic, and now they feel empowered to really let you have it. Going 10 miles south to trails in Jefferson County, and as long as you stay 6 feet or more, people smile and tell you to have a nice hike.
[deleted]
In my city many small streets have been closed to traffic. Haven't seen anyone complain about runners/bikers not using masks in the street. But we have more than a few runners on those same blocks not masking on the sidewalk.
> for whatever good it will do...
None at all. I’ve taken to getting my daily exercise in the early morning and late evening just to avoid talking to/arguing with my neighbors/the busybody brigade. The fact that I walk well out into the street when there aren’t any cars keeping roughly 15 to 30 feet from just about anyone and line of sight on everyone around me does not change this.
None at all. I’ve taken to getting my daily exercise in the early morning and late evening just to avoid talking to/arguing with my neighbors/the busybody brigade. The fact that I walk well out into the street when there aren’t any cars keeping roughly 15 to 30 feet from just about anyone and line of sight on everyone around me does not change this.
> just to avoid talking to/arguing with my neighbors/the busybody brigade
You're right that avoidance is the best bet here, for the time being.
These are people that have been manipulated and fixed with beliefs inserted into their reptile brain.
This is not the neocortex speaking - arguing on the basis of reason (pointing to a study) will not convince them that a mask is unnecessary away from people, in a field or outdoors.
They must be engaged in the same way they were manipulated - by appealing to emotion. It's a tough nut to crack.
You're right that avoidance is the best bet here, for the time being.
These are people that have been manipulated and fixed with beliefs inserted into their reptile brain.
This is not the neocortex speaking - arguing on the basis of reason (pointing to a study) will not convince them that a mask is unnecessary away from people, in a field or outdoors.
They must be engaged in the same way they were manipulated - by appealing to emotion. It's a tough nut to crack.
Unfortunately you’ve hit the mark. We just have to pick our battles.
Where on earth do you live that any one at all is wearing a mask hiking?
I wore one on my last hike -- and in fact, the hiking trail was the most crowded place I've been in months. Parks all over the US have seen record-breaking attendance figures this year.
In the SF Bay Area, where the hiking is amazing, the majority of people I see are wearing masks. We also have some of the lowest incidence of Covid in the US for the density and population.
Personally, I figure if I can smell someone smoking as I pass them on the street, even with a KN95 mask on, it's probably a good idea to wear a mask all the time.
Personally, I figure if I can smell someone smoking as I pass them on the street, even with a KN95 mask on, it's probably a good idea to wear a mask all the time.
In Massachusetts, it's very common although not universal. (And many, like myself, tend to pull up a gaiter when I get near, especially mask-wearing, other people.)
I see plenty of people wearing masks while hiking in Umstead State Park in Raleigh NC.
I cycle (hard!), I wear a mask. People I pass wear a mask. Jeez, people -wear a mask.
It can't be that difficult...to breathe heavily, or contain such, far from others?
> I cycle (hard!), I wear a mask. People I pass wear a mask. Jeez, people -wear a mask
I'm all for wearing masks and I do it.
But not when road biking where I very rarely (1 in 20 rides) come within 20 feet of a human being, other than people driving by me at 55 mph.
I also don't wear a mask when running, for the same reason.
Maybe if you're running / biking on the sidewalks of NYC, then sure, wear a mask! But on an empty country road outside of major cities?
I'm all for wearing masks and I do it.
But not when road biking where I very rarely (1 in 20 rides) come within 20 feet of a human being, other than people driving by me at 55 mph.
I also don't wear a mask when running, for the same reason.
Maybe if you're running / biking on the sidewalks of NYC, then sure, wear a mask! But on an empty country road outside of major cities?
The entire idea of this suspended river of particulate over trails is just ridiculous. As contagious as this disease is, what do people think the odds are they will catch it from their 5 second, 10 foot interaction?
If you harass someone on a bike path who wears a mask in their regular social activities all you do is (1) not focus on the real challenge and (2) frustrate and discourage someone who's on the same team
Yeah it is definitely about context. I live in a suburban area. For most of my bike rides I can bike in the street and get 12+ ft if distance. But every once in a while I have to go in a bike lane or on the sidewalk and then I wear my mask.
I know the chances of transmission between me riding my bike and a pedestrian are low, but it feels easy to be cautious.
I know the chances of transmission between me riding my bike and a pedestrian are low, but it feels easy to be cautious.
One thing I've learned through all of this is that my allergies are a lot better when I wear a mask while exercising outside. So yeah, I wear one every time. FWIW.
I've noticed this as well, and will probably continue to wear a mask of some sort during hay-fever season once the pandemic is over.
dustinmoris(2)
The problem is when you pass other people on the trail and it's not possible to maintain a proper physical distance in passing.
Also, people seem to think the virus magically stops at an invisible 6 foot distance whereas in reality you need much more if you're breathing and running where you leave a much bigger trail of aerosolized particles as you run, and there's also wind carrying your breath much further than in a still situation.
I do take mask off for hikes when nobody is in sight but I always put it on when I see people are about to pass. What's annoying is people who don't put their mask on to pass you and don't stop and wait for both sides to have mask on before passing. I've been forced multiple times to abruptly stop and backtrack my steps to maintain distance while fiddling my mask on because the other person kept pressing forward impatiently.
Also, people seem to think the virus magically stops at an invisible 6 foot distance whereas in reality you need much more if you're breathing and running where you leave a much bigger trail of aerosolized particles as you run, and there's also wind carrying your breath much further than in a still situation.
I do take mask off for hikes when nobody is in sight but I always put it on when I see people are about to pass. What's annoying is people who don't put their mask on to pass you and don't stop and wait for both sides to have mask on before passing. I've been forced multiple times to abruptly stop and backtrack my steps to maintain distance while fiddling my mask on because the other person kept pressing forward impatiently.
>Also, people seem to think the virus magically stops at an invisible 6 foot distance whereas in reality you need much more if you're breathing and running where you leave a much bigger trail of aerosolized particles as you run, and there's also wind carrying your breath much further than in a still situation.
But people also think (without evidence) that momentary contact closer than 6 feet is enough to spread COVID. It's almost certainly not.
You are very very very very unlikely to get COVID passing by a person for 2 seconds without wearing a mask. The infected person would have to sneeze directly into your mouth or something.
But people also think (without evidence) that momentary contact closer than 6 feet is enough to spread COVID. It's almost certainly not.
You are very very very very unlikely to get COVID passing by a person for 2 seconds without wearing a mask. The infected person would have to sneeze directly into your mouth or something.
No offense, but it's not really feasible on a trail with any level of traffic to wait for each passerby to put their mask on.
Just wear it as a chin-strap and it takes 2s to pull up and adjust. Accept that sometimes, your mask will be your only defense, and then hiking is almost as easy as ever before.
Just wear it as a chin-strap and it takes 2s to pull up and adjust. Accept that sometimes, your mask will be your only defense, and then hiking is almost as easy as ever before.
I have started to just hold my breath while passing people on a trail. Problem solved?
To be honest, slipping a mask on (or pulling up a neck gaiter) when approaching people on the trail (especially if they're wearing masks), I just see it as a polite gesture even if I'm skeptical it makes the slightest bit of difference. Mostly I generally avoid going places where I'm likely to have to pass a lot of people.
Implying there was a problem to begin with. Where's the evidence of people catching this from 2 seconds spent next to someone else while walking nearby outdoors in opposite directions? You think that somehow that's not OK, but sitting 6 feet from someone indoors is?
(a) I don't sit 6 feet from someone indoors either.
(b) The problem is we don't know, and I'm in a risk group, so I don't want to take chances until something is proven to be safe.
(b) The problem is we don't know, and I'm in a risk group, so I don't want to take chances until something is proven to be safe.
Is this sarcasm or are you suffering from anxiety?
It's really hard for me to hold my breath going uphill, and also there's a huge wafting trail of aerosolized particles for 20+ feet behind other runners, so if I'm walking and they're running I'd have to hold my breath for longer than I can. Have you seen the simulations?
I tend to consider not wearing a mask like smoking near some non smoker (I'm a smoker BTW).
The risk of them getting a serious disease caused by the smoke of my cigarette is non existent, if I am far enough the smell also is not strong enough to be of real disturbance, but I see their faces and I don't blame them, since I am the one doing something that is notoriously annoying and it costs me nothing, I don't smoke if there are non smokers around and I can't avoid them or am the only one smoking.
On the other hand I can't stand loud people and when I meet one, I ask them to lower their voices.
Wearing a mask it's the same thing: it costs nothing and wearing one prevents misunderstandings, while also adding a [nobody knows exactly how effective] additional layer of protection that does not hurt.
The risk of them getting a serious disease caused by the smoke of my cigarette is non existent, if I am far enough the smell also is not strong enough to be of real disturbance, but I see their faces and I don't blame them, since I am the one doing something that is notoriously annoying and it costs me nothing, I don't smoke if there are non smokers around and I can't avoid them or am the only one smoking.
On the other hand I can't stand loud people and when I meet one, I ask them to lower their voices.
Wearing a mask it's the same thing: it costs nothing and wearing one prevents misunderstandings, while also adding a [nobody knows exactly how effective] additional layer of protection that does not hurt.
The other day I was driving down one of the major streets in Poughkeepsie, NY. There was an old woman sitting by herself on her front stoop, wearing a mask. The sidewalk was maybe 12 or 15 feet away, and there was no one out walking.
Best of luck pointing to the actual study. Are you going to print it out and carry it with you?
Please understand, I'm not criticizing you -- except to maybe point out that you place an awful lot of unfounded faith in your fellow human beings.
Best of luck pointing to the actual study. Are you going to print it out and carry it with you?
Please understand, I'm not criticizing you -- except to maybe point out that you place an awful lot of unfounded faith in your fellow human beings.
I do as that woman does for one reason: to socialize the normalcy of mask-wearing. It is as much a political statement as anything else, too. Wearing masks should be the norm, not the exception, and wearing one any time I'm in public reinforces that.
But if wearing a mask becomes a political statement there's bound to be a political statement to the contrary from the other side. I don't think that's a game we should play. Let's just follow the science where possible.
Risk probabilities also need to be taken into account. The science on mask wearing did change and it's possible it may change again if the virus evolves in the near future.
What won't change is the risk profile of wearing vs not wearing a mask. Wearing a mask despite necessity is an inconvenience, but unlikely to result in harm. Not wearing mask, even if current science says is safe to do so, is still exposure to potential harm that may have been unforeseen. For instance a transmission vector that is not yet a well characterized one. This is why I personally take a dim view to these sorts "following the science" arguments.
What won't change is the risk profile of wearing vs not wearing a mask. Wearing a mask despite necessity is an inconvenience, but unlikely to result in harm. Not wearing mask, even if current science says is safe to do so, is still exposure to potential harm that may have been unforeseen. For instance a transmission vector that is not yet a well characterized one. This is why I personally take a dim view to these sorts "following the science" arguments.
I'm not opposed to erring on the side of caution where things are evolving fast and we may not have enough good science. What I'm opposed to is making political statements like this because it can easily backfire, especially when society is already very polarised.
Agreed. Although sometimes its easier not to fiddle with the mask taking it off and on again, especially if one doesn't have easy access to hand hygiene
This is the epitome of cargo-cult thinking. Why on earth should mask-wearing when not necessary be normalized?
You're right that it's political - except that it has actual detrimental consequences to society to normalize doing unnecessary things, especially when your goal is expressly to divide people (as that's literally the main thrust of what what "political statements" in the form of virtue signalling accomplish).
Rational, well-informed people should wear masks indoors and in busy outdoor areas, and enjoy some fresh air when they can get away from that. Wearing a mask when you don't need to to "reinforce" unnecessary behaviour is irrational, and will continue to make anyone who is anti-mask think that you're not approaching the situation reasonably.
You're right that it's political - except that it has actual detrimental consequences to society to normalize doing unnecessary things, especially when your goal is expressly to divide people (as that's literally the main thrust of what what "political statements" in the form of virtue signalling accomplish).
Rational, well-informed people should wear masks indoors and in busy outdoor areas, and enjoy some fresh air when they can get away from that. Wearing a mask when you don't need to to "reinforce" unnecessary behaviour is irrational, and will continue to make anyone who is anti-mask think that you're not approaching the situation reasonably.
It isn't a big deal to wear a mask all the time. I wear one in my workshop when alone all day. I semi-regret donating all my N95 masks last spring - I still cannot get good replacements and I'm allergic to sawdust.
There is no harm in wearing a mask when you don't need to. there is harm in messing up some borderline cases. So just get used to it on your face and forget about it.
Yeah, no, every time I see specious reasoning like this it just makes me resent having to wear a muzzle more. I'll still do it when it makes sense, but I can't understand why anyone wouldn't hate doing it.
I hear this from a lot of people, so it must be real, but I honestly do not get it. If the masks fits well you forget it is even on.
Do you, like, not exercise or something? Do you walk really slowly, so you don't need a lot of air? Are your lungs just dryer than most people's? Do you never wear glasses, sun or optical?
Industrial supply shops tend to have valved disposable respirators, and cartridge respirators in stock, especially in NIOSH ratings other than N95. The Honeywell cartridge respirators are awesome for dealing with sawdust.
Beware the risks of doing things just for appearances and encouraging others to do so, it gives weight to the people who deny mask wearing does anything.
It really bothers me when the CEO of that health company was being harrassed for not wearing a mask after he has recovered from an infection, the mask would do nothing for him or anybody else, but he wasn’t using it as a political statement so he was doing wrong?
It really bothers me when the CEO of that health company was being harrassed for not wearing a mask after he has recovered from an infection, the mask would do nothing for him or anybody else, but he wasn’t using it as a political statement so he was doing wrong?
But in a time of extreme public anxiety, and especially one where the topic of taking some action to try to avoid unknowingly infecting your community has become controversial on its own, is doing a simple thing which signals to the people around you that you're likely taking some level of precaution and are understanding of public health guidelines not worth its benefits to the community?
Some kinds of signaling are useless at best, problematic at worst. But wearing a mask even if you believe you technically don't require one to avoid being contagious seems like a common sense way to promote community during a stressful time to be around strangers - they don't know you, they don't know your medical history, they have no way of knowing when you wait near eachother in the grocery checkout line whether you're carrying antibodies and presumably not capable of being contagious or whether you're just flagrantly ignoring public health advice.
(Ignoring, of course, the subset of people who would inevitably falsely assume they were not capable of being contagious for whatever reasons even if they really could be... we probably all know that friend who swears they had COVID earlier in the year, but did not get tested at the time and have not had an antibody test since to verify. Do we really want those people getting the idea that their anecdotal illness is an opt-out from face coverings in public?)
The many interpretations of public health messaging around the world have shown us pretty well over the last 8 months that many people do really poorly with developing science and/or nuance. "Wear your mask in public, always" removes a lot of room for error, either malicious or just misinformed.
Some kinds of signaling are useless at best, problematic at worst. But wearing a mask even if you believe you technically don't require one to avoid being contagious seems like a common sense way to promote community during a stressful time to be around strangers - they don't know you, they don't know your medical history, they have no way of knowing when you wait near eachother in the grocery checkout line whether you're carrying antibodies and presumably not capable of being contagious or whether you're just flagrantly ignoring public health advice.
(Ignoring, of course, the subset of people who would inevitably falsely assume they were not capable of being contagious for whatever reasons even if they really could be... we probably all know that friend who swears they had COVID earlier in the year, but did not get tested at the time and have not had an antibody test since to verify. Do we really want those people getting the idea that their anecdotal illness is an opt-out from face coverings in public?)
The many interpretations of public health messaging around the world have shown us pretty well over the last 8 months that many people do really poorly with developing science and/or nuance. "Wear your mask in public, always" removes a lot of room for error, either malicious or just misinformed.
If you’re doing it for virtue signaling and the people who think it’s nothing but virtue signaling can tell because you’re open about your motivation, doing something for appearances harms the good you’re actually trying to accomplish.
Thanks for being the hero our society needs.
What's occurred to me in the last few weeks is that a good number of people who, no doubt, watch films or read books where the theme is conformity have no idea the works are about them.
Wearing a mask indoor: yes
Wearing a mask outdoor: no
Wearing a mask outdoor: no
Pulling the mask up and down is unsafe for several reasons. First of all, you touch your face. Chinese scientists insist on fomite transmission being real. Second, more importantly, you need your mask tightly fit, to protect others. If you keep fiddling with it, moving up and down, it wont be tight after second or third time you do this. And from the social point of view it is just a bad signal. Period.
While I believe this study will be proven over time, it is just one study. Since it's getting colder I am keep most of my exercising inside, but when over the summer I masked up when doing outdoor activities just to be safe for myself, and to make others feel better.
Here is an aggregation of studies that come to various conclusions regarding masks.
https://aapsonline.org/mask-facts/
Here is an article from July about mask usage in Europe.
https://www.economist.com/graphic-detail/2020/07/08/face-off...
https://aapsonline.org/mask-facts/
Here is an article from July about mask usage in Europe.
https://www.economist.com/graphic-detail/2020/07/08/face-off...
re: The Economist. "Mask wearing" attitudes in general don't mean much in the context of people who are looking for 100% wearing once you step out of your own door. There are a lot of places that are very compliant indoors, and relatively so outdoors in crowded areas, but not where they're mostly distanced outdoors. To many people, that looks fine. To others, it's horrible.
It's definitely not the first study, I've seen at least 2 or 3 other since March (no links though, sorry). Also the only study that suggested the opposite was a simulation that I think wasn't even peer-reviewed.
> I tried to explain
... which is why I simply wear a mask while hiking. :)
... which is why I simply wear a mask while hiking. :)
I'm very pro-mask as a reasonable measure for controlling transmission however masks have been politicized and turned into a symbol of in/out group dynamics on both the left and the right. Masks are now triggers to the extremists on both sides and it's impossible to act reasonably and please either group as I'm either seen as a fascist anti-masker or a recruit in the red army. It seems the loud minority on both sides can only think in a Hitler/Stalin dichotomy with zero nuance. I choose to ignore the unreasonable and do what I think is good and reasonable and above all charitable, despite the discomfort.
Good for you. Fortunately where I live mask wearing is not a political statement and therefore people use common sense and their brain to evaluate when and where to wear a mask and everything is very relaxed and fluid. When mask wearing becomes a political symbol then all logic is out of the window and you get crazy mental ideologists on both sides destroying it for everyone. We should make a list of all those people on both sides and maybe one day that list might become useful lol.
It's mind-boggling to me that people act so irrationally. Maybe one won't get very ill if they are infected with Covid-19. But it's also possible that they'll inadvertently pass it on to others who may become gravely ill (or worse.)
What does it cost you to wear a mask? It's uncomfortable and annoying - I agree! If we make mask-wearing complicated (over nose, under nose, under the chin!) people will just do the most comfortable thing and it'll wind up being completely ineffective.
The coronavirus doesn't care if you are republican or democrat.
Simple rule: wear a mask when there's other people around - your life may not depend on it, but your or someone else's grandmother's might. If a vaccine is truly around the corner, we can actually cause some people not to die by wearing masks. There's just no good reason to be this selfish, prolonging this nightmare in the process.
What does it cost you to wear a mask? It's uncomfortable and annoying - I agree! If we make mask-wearing complicated (over nose, under nose, under the chin!) people will just do the most comfortable thing and it'll wind up being completely ineffective.
The coronavirus doesn't care if you are republican or democrat.
Simple rule: wear a mask when there's other people around - your life may not depend on it, but your or someone else's grandmother's might. If a vaccine is truly around the corner, we can actually cause some people not to die by wearing masks. There's just no good reason to be this selfish, prolonging this nightmare in the process.
If you don't have Covid then the only way to get Covid is to be exposed to someone who is contagious. I know that's stating the obvious. The point is, if you're outside and with no one but yourself, and not close to anyone else, there's no risk. A passing squirrel or a bird is not going to infect anyone.
People walking solo in open spaces with masks on - which I see a couple times per week on my morning run - perpetuates a scientifically false narrative. I'm not going to object. If that makes them comfortable. But it's also a false sense of comfort. I'm not sure that's a good thing.
People walking solo in open spaces with masks on - which I see a couple times per week on my morning run - perpetuates a scientifically false narrative. I'm not going to object. If that makes them comfortable. But it's also a false sense of comfort. I'm not sure that's a good thing.
Mask is mandatory outdoors all the time in the big cities in France. Sometimes I think it’s just the government taking revenge for when we mocked them for not being able to procure masks — having destroyed their stock of 1 billion masks a year before the pandemic. “You want mask? Ok, wear them now. Who feels stupid now?”
France's is a different dynamic. After the yellow vests events certainly the gov wants to reestablish it's place.
That aside, I'm not in a big city. I'm in the suburbs. I'm talking about the local park and such. My morning run is through a local small university, currently closed. I see more deer than people some mornings. In that context, I've seen people from a distance walking alone with a mask on. It's 8 am. No one else around. There's no scientific reason for a mask.
I believe masks are important. They are essential. But that's no justification for unnecessary masks. In fact, we should be conserving masks. Not wearing them when they're not necessary.
That aside, I'm not in a big city. I'm in the suburbs. I'm talking about the local park and such. My morning run is through a local small university, currently closed. I see more deer than people some mornings. In that context, I've seen people from a distance walking alone with a mask on. It's 8 am. No one else around. There's no scientific reason for a mask.
I believe masks are important. They are essential. But that's no justification for unnecessary masks. In fact, we should be conserving masks. Not wearing them when they're not necessary.
> If you don't have Covid
That's a big "if". When's the last time you were tested?
Because that's the actual reason to wear a mask. Preventing yourself from getting infected is less relevant than preventing yourself from infecting others.
> A passing squirrel or a bird is not going to infect anyone.
I don't know about those two animals specifically, but it is very much possible for COVID to spread via animals (that is, indeed, in all likelihood how the COVID pandemic started in the first place).
> People walking solo in open spaces with masks on - which I see a couple times per week on my morning run - perpetuates a scientifically false narrative.
No, it perpetuates a narrative of "it's better to be safe than sorry", which is about as scientific of a narrative as it gets when it comes to infectious diseases. I wear my mask when out walking or hiking specifically because I don't trust others to keep their distance, and because I care more about the possibility that I might inadvertently spread COVID to someone who'd die from it than I do about messing up my beard with a mask.
That's a big "if". When's the last time you were tested?
Because that's the actual reason to wear a mask. Preventing yourself from getting infected is less relevant than preventing yourself from infecting others.
> A passing squirrel or a bird is not going to infect anyone.
I don't know about those two animals specifically, but it is very much possible for COVID to spread via animals (that is, indeed, in all likelihood how the COVID pandemic started in the first place).
> People walking solo in open spaces with masks on - which I see a couple times per week on my morning run - perpetuates a scientifically false narrative.
No, it perpetuates a narrative of "it's better to be safe than sorry", which is about as scientific of a narrative as it gets when it comes to infectious diseases. I wear my mask when out walking or hiking specifically because I don't trust others to keep their distance, and because I care more about the possibility that I might inadvertently spread COVID to someone who'd die from it than I do about messing up my beard with a mask.
If you're alone and no one is within 10+ yards of you, who is going to be infected? I agree with your concerns. I simply don't see the need for the unnecessary. We need a steady state of vigilance. Fear inflation only leads to fatigue. That's not helpful.
> If you're alone and no one is within 10+ yards of you, who is going to be infected?
If someone unexpectedly approaches and gets within 10 yards of me, how long will it take me to put on my mask? Can I do so before that person's within 2 yards?
Better to just leave it on and leave it be rather than spend all day fumbling with it. That is:
> We need a steady state of vigilance.
Wearing a mask when out in public is that steady state. Taking it off because you think you're alone is a deviation from that steady state.
If someone unexpectedly approaches and gets within 10 yards of me, how long will it take me to put on my mask? Can I do so before that person's within 2 yards?
Better to just leave it on and leave it be rather than spend all day fumbling with it. That is:
> We need a steady state of vigilance.
Wearing a mask when out in public is that steady state. Taking it off because you think you're alone is a deviation from that steady state.
I think it's patronizing to assume that someone is doing something out of a "false sense of comfort" instead of simply that it's easier for them to wear a mask 100% of the time than to take it on/off whenever they come near someone.
The open spaces by me are very narrow. When overtaking someone or passing by someone going the opposite direction, you can't avoid being close to them. Sure, it's brief, but you should probably have a mask on for that. For some people mask on/mask off is a lot more hassle than just leaving it on.
Yes, this. I can feel a nice cloud of moisture coming off runners that pass too close on the trails.
I think the key difference with the outdoors is that aerosols don’t accumulate easily, not that you couldn’t infect someone by blasting them with your breath.
I think the key difference with the outdoors is that aerosols don’t accumulate easily, not that you couldn’t infect someone by blasting them with your breath.
Reading your comment, it's unclear how far you're keeping from others. The only information is that other people don't feel safe given your distance and lack of mask.
It's analogous to you feeling like you're a safe driver but having passengers asking you to slow down. If you're not judging the danger to others commensurately to them, it seems like the onus should be on you to adjust your behavior.
Also, as others pointed out, this study's idea of "crowded spaces" might not align with your idea of it. If someone with COVID-19 passed me on an average-sized trail path or sidewalk breathing heavily while running, I wouldn't feel safe and I doubt many other reasonable people would either. It's not an issue of outside air vs. inside air as it is whether you end up breathing the same air as others, and you might not be a great judge of when that is or how it applies to this study.
Also, if you're interested in backing up your actions with studies, you should note that "social distancing" meaning 6ft distance which I'm assuming you're referring to has been debunked by MIT and Oxford studies.
Figuring out exactly what's safe and not is not clear cut, which is why simple rules like "wear a mask outside" is so important, because we clearly can't all be trusted to make good judgment calls.
It's analogous to you feeling like you're a safe driver but having passengers asking you to slow down. If you're not judging the danger to others commensurately to them, it seems like the onus should be on you to adjust your behavior.
Also, as others pointed out, this study's idea of "crowded spaces" might not align with your idea of it. If someone with COVID-19 passed me on an average-sized trail path or sidewalk breathing heavily while running, I wouldn't feel safe and I doubt many other reasonable people would either. It's not an issue of outside air vs. inside air as it is whether you end up breathing the same air as others, and you might not be a great judge of when that is or how it applies to this study.
Also, if you're interested in backing up your actions with studies, you should note that "social distancing" meaning 6ft distance which I'm assuming you're referring to has been debunked by MIT and Oxford studies.
Figuring out exactly what's safe and not is not clear cut, which is why simple rules like "wear a mask outside" is so important, because we clearly can't all be trusted to make good judgment calls.
The study makes several references to "crowded" areas, and concludes that outdoor air is "safe" apart from these spaces. However, I was unable to find any clarification for what constitutes a "crowded" space (or not). I am not sure what the benefit of this study is supposed to be absent such a definition - am I missing something?
My reading is that the authors were unable to find any air with appreciable COVID levels, but they’ve just added the caveat that maybe they didn’t find a sufficiently crowded area to take a sample.
I would assume "crowded areas" are areas where there are more than 1 person per [pi * <social distance recommendation>^2]
So as a rough example, let's say social distancing recommendation is 6ft (this changes by jurisdiction). Then for a football field to be "crowded" you would need more than 57,600 / (pi * 36) = ~510 people evenly distributed on it. If the social distancing recommendation is 20ft, then you can only have 57,600 / (pi * 400) = 45 people on the football field before it starts getting crowded.
So as a rough example, let's say social distancing recommendation is 6ft (this changes by jurisdiction). Then for a football field to be "crowded" you would need more than 57,600 / (pi * 36) = ~510 people evenly distributed on it. If the social distancing recommendation is 20ft, then you can only have 57,600 / (pi * 400) = 45 people on the football field before it starts getting crowded.
One day after LA county shuts down all outdoor restaurant dining, with no relief/bailout for service industry businesses or workers in sight.
https://la.eater.com/platform/amp/2020/11/22/21590433/corona...
https://la.eater.com/platform/amp/2020/11/22/21590433/corona...
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The Federal Government is completely failing here. States can't run deficits, usually by force of law. They'd rather confirm judges than pass legislation to help, all of this damage is completely self-inflicted.
That's not a Federal issue. States might not be able to run deficits in quite the same way that the Federal government can but if States need additional revenue to support favored businesses then they can certainly raise taxes.
Some state governments such as Florida allow restaurants to remain open. We can debate whether that is a good policy from a pandemic control standpoint, but why should Floridians pay Federal taxes to support restaurants that were forcibly shut down by a California county?
Some state governments such as Florida allow restaurants to remain open. We can debate whether that is a good policy from a pandemic control standpoint, but why should Floridians pay Federal taxes to support restaurants that were forcibly shut down by a California county?
Raising taxes in a downturn is a ridiculous idea and we should pay everyone to stay shut until the virus is under control.
You could also ask why Californians should pay the Medicare taxes associated with Florida's much higher rate of COVID infection due to their opening of restaurants and the state's higher elderly population.. We're all in this together, the economy won't be back to normal until Covid is gone and all of these ridiculous states flaunting obvious public health rules are costing everyone much more than it would take to just pay restaurant employees and everyone else to stay home for a few more months.
You could also ask why Californians should pay the Medicare taxes associated with Florida's much higher rate of COVID infection due to their opening of restaurants and the state's higher elderly population.. We're all in this together, the economy won't be back to normal until Covid is gone and all of these ridiculous states flaunting obvious public health rules are costing everyone much more than it would take to just pay restaurant employees and everyone else to stay home for a few more months.
The money to pay for bailouts has to come from taxes, otherwise we just create inflation which causes other problems.
It's still a valid concern. The government has mandated these businesses shut their doors it should also mandate that they get the assistance needed (which I'm hoping will come next year).
Small businesses can't afford a lot of the overhead of shuttering their doors and still paying mortgages etc. The employees there can't afford it either. I'm not saying it's a bad/good call by leaders. I'm just saying if you are mandated to shut your business, you should be able to "turn off" the economic issues associated with that. Mortgage gets extended, taxes get deferred, etc.
This is definitely a weakness of pure capitalism in a regulation environment like today. We cant shut down a businesses income and expect their expenses to remain the same.
Small businesses can't afford a lot of the overhead of shuttering their doors and still paying mortgages etc. The employees there can't afford it either. I'm not saying it's a bad/good call by leaders. I'm just saying if you are mandated to shut your business, you should be able to "turn off" the economic issues associated with that. Mortgage gets extended, taxes get deferred, etc.
This is definitely a weakness of pure capitalism in a regulation environment like today. We cant shut down a businesses income and expect their expenses to remain the same.
In a free market, the government doesn't have the right to take the decision away from the individual about how much risk they can tolerate. Some politicians infringing on the rights of others doesn't justify further intrusions on the natural rights of others.
We don't have a free market, or we wouldn't have fire departments, police departments, schools, military, funding for crops, or any government budgets.
The idea that we are a pure free market is as absurd as saying that china is pure communism. There is no pure government out there that meets the academic definition of the market they espouse. It's just not possible, never has been, never will be (I usually don't speak in absolutes but feel pretty 99.999% comfortable with this statement). There will always be gray outside the academic setting.
The idea that we are a pure free market is as absurd as saying that china is pure communism. There is no pure government out there that meets the academic definition of the market they espouse. It's just not possible, never has been, never will be (I usually don't speak in absolutes but feel pretty 99.999% comfortable with this statement). There will always be gray outside the academic setting.
It also fails at a more practical sense too - "The freedom to swing your arm stops at my face." People "choosing" to not wear a mask and to go to restaurants where the staff can't similarly "choose" to not be there is just subjecting everyone else to infection. For its other merits, libertarianism absolutely fails in a pandemic when the only possible response is collective action. Americans have such a limited definition of freedom it's almost comical.
> "The freedom to swing your arm stops at my face."
Err not really, if you go full swing on someone and you "intended" to stop but they block your arm and punch you in the face, arguably it's your fault. If they kill you with that punch then they would be at fault. The law around freedom is really complex. Freedom in the US isn't limited, it's complicated.
When American's use the word freedom most of them are being dumb. You do have freedoms that are protected, but that doesn't mean what you think is a freedom actually is a freedom.
I'm also going to pick on your example of the restaurant. The staff at a restaurant does get to choose to be there or not, that's a free economy. If the government shuts down restaurants, like they have in some states, then the staff can no longer choose to take on that risk. Everyone gets to choose, but there is also an obligation/responsibility with freedom that people in the USA don't seem to "get".
You are FREE to get a gun, you are then responsible for using it wisely. Lock it up, get trained with it, be safe, and learn when to pull it out. The jerks on CNN who had the rifle and were pointing it at the crowd are a great example of irresponsibility with freedom. They should have never, EVER pointed a gun at someone who did not pose an imminent threat to their person. Back to the punching example, everyone who sees a fake punch can judge HOW fake it was. Did they stop at the nose, did they just jerk their arm, did they go Suuuppppeeerrrrr slow. Those judgements matter in court to show that the person who fought back was being reasonable. The burden of reasonable action is even higher with a knife/gun.
Take free speech for example, you can actually sign away your right to free speech in a contract. There is a commedian who talks about things that are illegal to say. Free speech applies to the press, not to individuals being ass hats.
Anyway, all of that is me saying, freedom in the USA is a slogan, which is dumb. Meme's do not present great arguments, but the freedoms we do have are as well defined under the law as most place. People just don't know them.
Err not really, if you go full swing on someone and you "intended" to stop but they block your arm and punch you in the face, arguably it's your fault. If they kill you with that punch then they would be at fault. The law around freedom is really complex. Freedom in the US isn't limited, it's complicated.
When American's use the word freedom most of them are being dumb. You do have freedoms that are protected, but that doesn't mean what you think is a freedom actually is a freedom.
I'm also going to pick on your example of the restaurant. The staff at a restaurant does get to choose to be there or not, that's a free economy. If the government shuts down restaurants, like they have in some states, then the staff can no longer choose to take on that risk. Everyone gets to choose, but there is also an obligation/responsibility with freedom that people in the USA don't seem to "get".
You are FREE to get a gun, you are then responsible for using it wisely. Lock it up, get trained with it, be safe, and learn when to pull it out. The jerks on CNN who had the rifle and were pointing it at the crowd are a great example of irresponsibility with freedom. They should have never, EVER pointed a gun at someone who did not pose an imminent threat to their person. Back to the punching example, everyone who sees a fake punch can judge HOW fake it was. Did they stop at the nose, did they just jerk their arm, did they go Suuuppppeeerrrrr slow. Those judgements matter in court to show that the person who fought back was being reasonable. The burden of reasonable action is even higher with a knife/gun.
Take free speech for example, you can actually sign away your right to free speech in a contract. There is a commedian who talks about things that are illegal to say. Free speech applies to the press, not to individuals being ass hats.
Anyway, all of that is me saying, freedom in the USA is a slogan, which is dumb. Meme's do not present great arguments, but the freedoms we do have are as well defined under the law as most place. People just don't know them.
Good to see some research on this. Where I live, mask rules have been relaxed outdoors as long as one can maintain social distancing. It is still mandatory to carry a mask with you everywhere should you run into a crowd and can’t maintain distance.
I am still going to be wearing mine everywhere until I can get vaccinated.
I am still going to be wearing mine everywhere until I can get vaccinated.
Wow. Where is this, if I may ask?
Here in Finland, there is no mandatory mask usage, largely because the government hasn't been able to find a constitutionally acceptable way of mandating it. Instead, we have increasingly stern "recommendations". OTOH, the situation is relatively well in hand here still, so I suppose the political pressure to act is not as heavy as it is elsewhere.
Here in Finland, there is no mandatory mask usage, largely because the government hasn't been able to find a constitutionally acceptable way of mandating it. Instead, we have increasingly stern "recommendations". OTOH, the situation is relatively well in hand here still, so I suppose the political pressure to act is not as heavy as it is elsewhere.
The Netherlands has a mask rule that doesn't even require you to wear them inside with other people around. If I am not mistaken the requirement is that you are required to wear them when you cannot maintain the 1.5M distance, but that of course is just shifting the enforcement to the business owners instead of the government. In any other situation you are strictly recommended to wear them.
I don't get why the Dutch government and the 'average' dutch person isn't wearing it all the time. People still consider it 'weird' to wear it and even in the capital city (Amsterdam) people look at me weirdly when I wear it outside. About 10% isn't wearing it in stores or even the airport is a place where people still skip out on the face mask. They should just enforce this rule instead of closing other places where it is actually possible to maintain the distance.
I don't get why the Dutch government and the 'average' dutch person isn't wearing it all the time. People still consider it 'weird' to wear it and even in the capital city (Amsterdam) people look at me weirdly when I wear it outside. About 10% isn't wearing it in stores or even the airport is a place where people still skip out on the face mask. They should just enforce this rule instead of closing other places where it is actually possible to maintain the distance.
Victoria, Australia. It was relaxed just this Sunday after three weeks of no new cases and no community transmission. However given the progressive relaxation of rules over the past month, some of us are rightly concerned and choose to wear masks and avoid indoor venues whenever possible.
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Similar results to a paper (April, China), where of 1245 confirmed cases only 1 outbreak (involving 2 people) was found to have happened outdoors:
https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v...
Is virus exposure a threshold mechanism (some form of initial defense exists that gets saturated at some point) or is exposure to more virions simply the equivalent of a higher number of lottery tickets from the virus perspective?
I seem to remember having read wording in one of the many papers that we surely all skimmed in 2020 that looked suspiciously like a statement declaring side in a scientific community that still considered both possible. (something like "We are working with the Independent Probability per Virion Assumption here" or something like that.
I seem to remember having read wording in one of the many papers that we surely all skimmed in 2020 that looked suspiciously like a statement declaring side in a scientific community that still considered both possible. (something like "We are working with the Independent Probability per Virion Assumption here" or something like that.
It's not a threshold.
For getting infected, it's like lottery tickets.
For severity of infection, a bunch of "winning" lottery tickets make it difficult for your immune system to catch up. Getting a large exposure is like giving the virus multiple viral generations of a head start without being noticed by the immune system.
For getting infected, it's like lottery tickets.
For severity of infection, a bunch of "winning" lottery tickets make it difficult for your immune system to catch up. Getting a large exposure is like giving the virus multiple viral generations of a head start without being noticed by the immune system.
It's a combo of both, actually!
I believe the other salient factor is the coefficient of my-immune-system-tends-to-implode per unit of viral load, which may or may not vary a lot between different people. Although at this point maybe it's hard to tell if the different outcomes are more to do with differences in processing the virus or differences in magnitude of viral load at time of acquisition.
Is there really much of a difference between one and the other?
The "lottery ticket" model is additive: 100 minor exposures adds up. The "threshold" model isn't: 100 minor exposures is no risk.
I get the sense that it's reasonable, and perhaps understood, that the magnitude of exposure is correlated with severity.
These comments have vastly reduced my opinion of HN.
In that case your opinion of HN may have needed some adjusting. Any large-enough population sample reflects the divisions in society at large—or societies, rather, since HN is a highly international site. There's no avoiding this.
Sometimes when people get shocked by what they read here, the shock experience has more to do with encountering voices that (often loudly and/or at length, and sometimes even eloquently) express opinions we don't run into in our circles. We're all pretty good at siloing ourselves among the like-minded. Even when we're aware that a topic is divisive, we don't relate much with people on the other side of the divide. Mostly we label them as idiots or worse, and don't encounter them in their complexity.
HN is a non-siloed site [1], meaning we're all in one big room here, so it doesn't work that way. The reality is that on any divisive topic, there are millions if not billions of people on the other side of the divide, a bunch of them are here, and they tend to be otherwise normal people whose different beliefs derive from their different backgrounds rather than them being idiots or worse. One might think that makes for an easier experience, but in fact it makes things much harder.
I wrote a longer description of this a while ago if anyone is interested: https://news.ycombinator.com/item?id=23308098. Also https://news.ycombinator.com/item?id=23716395.
[1] https://hn.algolia.com/?query=silo%20by%3Adang&dateRange=all...
Sometimes when people get shocked by what they read here, the shock experience has more to do with encountering voices that (often loudly and/or at length, and sometimes even eloquently) express opinions we don't run into in our circles. We're all pretty good at siloing ourselves among the like-minded. Even when we're aware that a topic is divisive, we don't relate much with people on the other side of the divide. Mostly we label them as idiots or worse, and don't encounter them in their complexity.
HN is a non-siloed site [1], meaning we're all in one big room here, so it doesn't work that way. The reality is that on any divisive topic, there are millions if not billions of people on the other side of the divide, a bunch of them are here, and they tend to be otherwise normal people whose different beliefs derive from their different backgrounds rather than them being idiots or worse. One might think that makes for an easier experience, but in fact it makes things much harder.
I wrote a longer description of this a while ago if anyone is interested: https://news.ycombinator.com/item?id=23308098. Also https://news.ycombinator.com/item?id=23716395.
[1] https://hn.algolia.com/?query=silo%20by%3Adang&dateRange=all...
And my opinion of hacker news, already high, just got higher. Where else can you get to the very bottom of the comment thread for a random post, find one not particularly insightful or helpful comment, and then see it carefully replied to with intelligent and empathetic detail by the main curator of the service?
Thank you dang. I hope you are going to give yourself a holiday.
Thank you dang. I hope you are going to give yourself a holiday.
Me too.
There’s the obvious question, why not just wear a mask 100% of the time? There are no downsides, right?
There can be. Perhaps my mask had been in use for a while, I suspect it’s gotten dirty enough to be a potential health hazard, but I don’t have another mask to replace it? I’d still use it if people are around, but would try to reduce my exposure to it otherwise. Maybe I have asthma or some type of breathing difficulty, and wearing a mask makes it worse? I think those two are probably among the most common reasons.
There can be. Perhaps my mask had been in use for a while, I suspect it’s gotten dirty enough to be a potential health hazard, but I don’t have another mask to replace it? I’d still use it if people are around, but would try to reduce my exposure to it otherwise. Maybe I have asthma or some type of breathing difficulty, and wearing a mask makes it worse? I think those two are probably among the most common reasons.
I don't understand how the conclusion in the title can be drawn based on the data presented in the paper.
Basically, the researchers sampled 2 outdoor locations, and found low viral loads. Why is it reasonable to conclude that all outdoor non-crowded areas are safe?
I assume that not all outdoor environments are created equal. Variables like weather, wind, humidity, and population density probably all play a large factor in transmissibility. Certainly, more than 2 samples are required before making such a generalized conclusion?
Basically, the researchers sampled 2 outdoor locations, and found low viral loads. Why is it reasonable to conclude that all outdoor non-crowded areas are safe?
I assume that not all outdoor environments are created equal. Variables like weather, wind, humidity, and population density probably all play a large factor in transmissibility. Certainly, more than 2 samples are required before making such a generalized conclusion?
That's the last statement of the conclusion sections of the paper:
> Considering a typical inhalation rate of about 1 m3/h, as average between rest and light exercise (Adams, 1993), the concentrations would be low to spread the contagion via airborne transmission even assuming the mentioned increase of a factor 2.
> Considering a typical inhalation rate of about 1 m3/h, as average between rest and light exercise (Adams, 1993), the concentrations would be low to spread the contagion via airborne transmission even assuming the mentioned increase of a factor 2.
Yes, but the viral load measurements they're using were taken at only 2 different locations. I don't see why you would, then, feel confident in making a generalized statement about all locations.
The paper was about aerosolized virus. The title here misleadingly implies any kind of outdoor transmission (including droplet not just aerosol transmission) is unlikely.
We should all carry a weathervane with us and make sure that we're not in the received end of the airflow. Isn't it simpler to just freakin' wear lower-grade masks outside? I'm tired of self-entitled people who don't know why a saying like: "Better safe than sorry!" exists or "Hope for the best, plan for the worst!" Use common wisdom, and let's stop this redundant polemic about face masks as it only pours fuel into the fire and accomplishes nothing positive for the humanity!
Masks are one part of risk management, but they're not 100% effective. An effective strategy might involve wearing masks and social distancing and limiting how far you can travel and limiting the size of gatherings and banning indoor gatherings.
Wearing a mask is in many ways a lot like using a keep-cup: effective, but highly visible and a distraction from other useful measures.
Wearing a mask is in many ways a lot like using a keep-cup: effective, but highly visible and a distraction from other useful measures.
You confuse "one part" with "the essential part"!
No, I did not. Masks are around 67%[0] effective at protecting the wearer, but that's not enough to actually stop SARS-CoV-2 quickly, assuming it has an R0 somewhere around 3[1]. You cannot go about your day to day life like normal, wear a mask, and think you are doing your part, because 33% of 3 is still around 1, which means the number of infected will not be shrinking very quickly if at all.
You MUST stop going to large events, visiting friends and family indoors, going to restaurants, and work from home if you are able. This cannot be stated enough. Masks are necessary but not sufficient. They are neither 100% effective, nor effective enough to rapidly control SARS-CoV-2, unless used in conjunction with other measures.
[0] https://www.nature.com/articles/d41586-020-02801-8 [1] https://www.sciencedirect.com/science/article/pii/S259005362...
You MUST stop going to large events, visiting friends and family indoors, going to restaurants, and work from home if you are able. This cannot be stated enough. Masks are necessary but not sufficient. They are neither 100% effective, nor effective enough to rapidly control SARS-CoV-2, unless used in conjunction with other measures.
[0] https://www.nature.com/articles/d41586-020-02801-8 [1] https://www.sciencedirect.com/science/article/pii/S259005362...
Yeah, in a country where we require "face covering" not certified "face masks". Are people that cheap in the world's richest economy to not be able to afford buying a Level 3 surgical facemask for less than a dollar a piece?! Also, a big percentage of people do not wear masks properly - they are to fitted well, their nose is not covered, their chin is not covered, or a surgical face masks is used for more than 2 hours without being disinfected and dried up if it's gonna be reused!
I'm not in your country, whichever it is, and I think we're arguing past each other at the moment.
I am in favour of masks and agree with most things you've said about them.
I am also in favour of holding all your social and business activities outside, because masks are not enough by themselves.
In your original comment, you said that it would be simpler to wear masks than to take into account airflow differences between the open air vs indoors. I disagree with that: masks are not a simpler alternative to socialising outdoors, they are a necessary prerequisite. You must do both, not pick one or the other. Additionally, you should consider socialising less often, with a smaller group of people, and any other steps you can take without putting your mental health in jeopardy.
I am in favour of masks and agree with most things you've said about them.
I am also in favour of holding all your social and business activities outside, because masks are not enough by themselves.
In your original comment, you said that it would be simpler to wear masks than to take into account airflow differences between the open air vs indoors. I disagree with that: masks are not a simpler alternative to socialising outdoors, they are a necessary prerequisite. You must do both, not pick one or the other. Additionally, you should consider socialising less often, with a smaller group of people, and any other steps you can take without putting your mental health in jeopardy.
I agree. Even outside and wearing a N95/KN95/KF94/FFP2/FFP3 mask, I still keep a distance - the bigger, the better. Sometimes people get closer, I step backwards to keep the distance - I don't care what they think about it, all PPE does is to reduce the threat, it does not eliminate it completely. Also, when I'm being selfish, I make sure the wind blows into my back or sideways, ideally when there are no people around, not into my face. Very rarely for very brief moments and possibly when there's a possibility of people passing by, I could wear a ASTM Level 3 surgical mask, but I am not gonna wear a mask with no certification!
Also, it's surprised how people don't understand the fluid/air dynamics and actually want happens during basic activities. There are so many ways to breathe in concentrated contaminated air without even realizing it.
For example, getting a concentrated exposure when you open doors, when the the person at the drive-thru opens there small window and all the inside air flows right into your car, etc.
Well, of course, these are not highly contaminated spaces, but, still, we oversimplify things all the time.
Another vector is dog walking. In Spain, a study showed that dog owners have 78% change of getting COVID. How? Well, we know dogs and cats can carry the virus, so, you play with your dog with a mask, you give them the virus, they give it to the dogs they encounter during the walk, and that dog gives it to their owner.
Also, it's surprised how people don't understand the fluid/air dynamics and actually want happens during basic activities. There are so many ways to breathe in concentrated contaminated air without even realizing it.
For example, getting a concentrated exposure when you open doors, when the the person at the drive-thru opens there small window and all the inside air flows right into your car, etc.
Well, of course, these are not highly contaminated spaces, but, still, we oversimplify things all the time.
Another vector is dog walking. In Spain, a study showed that dog owners have 78% change of getting COVID. How? Well, we know dogs and cats can carry the virus, so, you play with your dog with a mask, you give them the virus, they give it to the dogs they encounter during the walk, and that dog gives it to their owner.
The title is highly editorialized misinformation. The study is saying that aerosolized virus is pretty much nonexistent outdoors (as everyone expected - fresh air works), but does not deny droplet transmission outdoors, which is what social distancing and mask wearing is designed to prevent.
From the abstract: "Transmission by contact or at close range due to large respiratory droplets is widely accepted, however, the role of airborne transmission due to small respiratory droplets emitted by infected individuals (also asymptomatic) is controversial"
From the abstract: "Transmission by contact or at close range due to large respiratory droplets is widely accepted, however, the role of airborne transmission due to small respiratory droplets emitted by infected individuals (also asymptomatic) is controversial"
I’ve paid very little attention but haven’t we known this for at least 4 months? Both the effectiveness of “indoor only” measures and the lack of spikes after BLM protests told us this.
We also know it’s airborne, worse if you’re old, obese or diabetic (which effects the immune system so no surprise there).
There seems to be a huge amount of effort and attention being put into covid research to reprove things we already knew. Is science always like this?
We also know it’s airborne, worse if you’re old, obese or diabetic (which effects the immune system so no surprise there).
There seems to be a huge amount of effort and attention being put into covid research to reprove things we already knew. Is science always like this?
So what happens if we put air purifiers with HEPA filter (1) indoors then? Has anyone measured this?
(1) HEPA filters have good filtration efficiency even at particle sizes smaller than MPPS https://www.sciencedirect.com/topics/engineering/high-effici... and an adequately powered one can recirculate room air in 10-15 minuters
(1) HEPA filters have good filtration efficiency even at particle sizes smaller than MPPS https://www.sciencedirect.com/topics/engineering/high-effici... and an adequately powered one can recirculate room air in 10-15 minuters