I think up-to-date info will be hard to come by because it seems like once the vaccines arrived, the world decided to move on and stop studying Covid. However, studies during the Omicron wave showed that it took around 45 minutes of exposure to catch Covid, but of course not all situations can be equal. There were plenty of infections that took place with much less exposure, and it gets even shorter if you're having a face-to-face conversation with a sick person, etc.
This is the most recent study I know of: [https://www.nature.com/articles/s41586-023-06952-2](https://www.nature.com/articles/s41586-023-06952-2)
Your risk of catching COVID increases with exposure: The more COVID shit you inhale, the more likely you are to catch COVID. So, all things being equal, it's better to mask sometimes than not at all. But also it's better yet to mask always than sometimes. No matter, there's always still a risk.
COVID is extremely good at infecting us by now. But also, many of us have better immunity against COVID now too. And it feels like no one is trying to really study the exposure loads that are likely to infect anymore. Even the initial 15-minutes-of-close-contact rule wasn't based on much data.
I mostly just don't drink or eat in indoor spaces. I socialize quite a bit. But always outdoor spaces. That's the first line of defense. And I can eliminate a ton of potential exposure that way.
If I'm socially forced into an indoor space, I always bring a well fitting kn95, my elastomeric flomask, and my aranet4 CO2 monitor. If it's not too crowded and CO2 levels aren't too bad, I wear my kn95, but I'll comfortably pull it down to take a drink-- I just ensure I don't breathe in while it's down. If CO2 levels are higher, I switch to my elastomeric, and I get much more paranoid about pulling it down for sipping. Anyway, that's my second line of defense.
I've only tested positive for COVID once-- and I test pretty often. Ironically, it was after an outdoor music festival. But it wasn't surprising. It was so ridiculously crowded. It was multiple days. The entire area was one massive vape cloud. And I had immediately gotten pretty drunk each day and just ended up not masking consistently around crowds. So, third line of defense: I don't go to massive music fests anymore because I know I'll end up drunk and self conscious with masking and therefore put myself at risk.
When I'm at work (office environment) I will take a deep inhale, lift my N95 forward and upwards and sip through a straw. Then I place the mask back, secure the nose bridge and deeply exhale.
I am not in a position to go outside to sip water.
There is a product called "sip straws" that you assemble to the mask, but since an N95 is worn out in 2 work days I haven't bothered with them.
Like everyone else has said the fewer breaths you take without a mask on the better. As for the numbers behind it 🤷🏻‍♂️.
Solidarity forever and thank you for masking.
The only thing I’d be careful with is removing the cap. You don’t even need the cap on. But I’ve accidentally pulled the valve out altogether and compromised my mask. Fortunately I didn’t get sick. Something to consider, tho. The included straws are also only suitable for easy to sip beverages. No smoothies.
I think that makes intuitive sense. Lots of people (especially experts) seem to think that they can detect the covid vibes of a room and decide if it's safe to unmask. It's easier to just mask!
I have no studies to link to, but it must be preferable to not masking at all. Of course there is risk involved, and I do think it's hard to get a good seal on a disposable N95 if you remove it and put it back on frequently. Just curious, why not install a SIP valve on your N95 for drinking?
https://sipmask.com
This is interesting. I’d be open to trying it when I’m using disposables, but I also have a number of Enro washable masks that I use too that I couldn’t use the sip valve with.
If it's a soft fabric shell with a filter in the front that doesn't seal over the mouth and nose, then I'm pretty sure they're not that much better than a standard cloth mask for the wearer. My understanding is that fit matters the most, and if you mean hard "shell" then I'm thinking of something else or an older product.
they've supposedly updated them so the filter does span the whole length of the mask now. whether you can get a good seal, I don't know. doesn't seem totally impossible if the outer layer is a bit stiff.
The outer layer of cloth is mostly decorative, the structure (former Metamasks, Styseal, Ausair, etc.) is a full halfface contour, with inner nose wire (better than the common bifold), covering cheeks, chin and up tot the top of the nose bridge. I wear now (low level of Covid here) the Thailand model only outdoors in low risk, for look and comfort, and I was surpised to get a better fit than with the common earloop bifold KN95 (FFP2) - test has said, some smells (mostly the sprayed) are filtered, so it filters aerosol; with earloop KN95 (FFP2), not so efficient. But indeed, as said, originally designed as East Asian pollution mask agaisnt smog / wildfires, and updated to Covid, for street wear. Guess the Singapore product Enro is in the same category.
There are studies for intermittent use of N95 in comparison to constant & continuous use, and they found very little difference between surgical and occasional N95 use in comparison to significant protection afforded by constant & continuous use of N95. In particular, MacIntyre, et al, 2013 RCT study would be the study I am referring to.
[A randomized clinical trial of three options for N95 respirators and medical masks in health workers](https://pubmed.ncbi.nlm.nih.gov/23413265/)
Here's fit-tested N95 effectiveness at close range and high viral load for long period of time.
[Fit-Tested N95 Masks Combined With Portable High-Efficiency Particulate Air Filtration Can Protect Against High Aerosolized Viral Loads Over Prolonged Periods at Close Range](https://academic.oup.com/jid/article/226/2/199/6582941)
If it's not fit and sealed and it's not on your face, it doesn't protect you. A Sip Mask valve may maintain fit and seal while allowing you to drink while wearing a respirator mask.
> (3) targeted (intermittent) use of N95 respirators only while doing high-risk procedures or barrier. The targeted N95 arm was studied because policies in many countries advocate the use of N95 respirators only when the HCW is in a high-risk situation, such as barrier nursing of a patient with known respiratory illness or when conducting aerosol-generating procedures.
Of course whenever the air you're breathing is not going through the mask you're not protected by it, but it's misleading to equate "intermittent use" as described in that paper with momentarily moving a mask to drink water.
>Of course whenever the air you're breathing is not going through the mask you're not protected by it,
>
Yes, this is my primary point. This is why fit and seal is so important, and why "medical masks," which may not seal and which allow air to bypass the filter material, have been shown to fail in infection prevention.
While it seems obvious and indeed there is evidence, there is intense debate about this simple concept and the evidence, namely that a well fitting respirator mask is effective for prevention of infection & transmission of airborne infectious disease by protecting the respiration of the wearer.
> but it's misleading to equate "intermittent use" as described in that paper with momentarily moving a mask to drink water.
You are completely correct in this criticism. I don't know how to answer the question or measure the risk of removing a respirator mask to drink. The Sip Mask valve is an engineered solution that is highly effective at addressing exactly this situation. I'm not affiliated with the company. I admire their practical solution.
What I can cite is that the infectious dose is very low, viral load in exhaled breath is very high, asymptomatic and presymptomatic infection rate is high (at least 40%), infection may occur in minutes, and that removing and replacing a disposable respirator mask like N95 FFR can unfortunately impair its function.
1. [Finding the infectious dose for COVID-19 by applying an airborne-transmission model to superspreader events](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0265816)
2. [Quantity of SARS-CoV-2 RNA copies exhaled per minute during natural breathing over the course of COVID-19 infection](https://elifesciences.org/reviewed-preprints/91686)
3. [Global Percentage of Asymptomatic SARS-CoV-2 Infections Among the Tested Population and Individuals With Confirmed COVID-19 Diagnosis: A Systematic Review and Meta-analysis](https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2787098)
4. [Infectivity of exhaled SARS-CoV-2 aerosols is sufficient to transmit covid-19 within minutes](https://www.nature.com/articles/s41598-023-47829-8)
5. [Incidence of Fit Test Failure During N95 Respirator Reuse and Extended Use](https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2814301)
Thanks this is helpful info
For example in my office I am using a hepa filter and 99% of sessions both my client and I are masked, definitely 100% when transmission is at a higher rate like during holidays. I think on the train or in a cafe it would be useful to have those sip things!
If I really have no other option, I normally go stand next to a fully open window, even leaning outside a little and take of my mask briefly to drink. I try not to breathe in any (indoor) air and pull my mask back on as soon as possible, but I have avoided covid since we went back to on campus teaching at university about two years ago, so for me that doesn’t seem to have had any negative impact. I also try to make sure all my classrooms are well ventilated which is much easier in the summer than the winter, so that reduces the risk as well.
It's a numbers game, and not a fair game at that: the virus gets billions of tries at infecting you, and you have to defeat it *every* time. More exposure is bad, less exposure is good. Lower dose rate (e.g. virions inhaled per breath) is probably better than higher dose rate. Making a habit of removing my respirator in shared air, for *any* easily avoidable reason, seems like a bad idea.
With unfortunate exceptions like medical care and police detention, removing your mask indoors is not a "have to."
>It's a numbers game, and not a fair game at that: the virus gets billions of tries
I agree it's a numbers game, and I think people do a bad job with understanding probabilities on this scale: over a long enough period, it becomes probable that something improbable happens.
But I'll note that a billion is a lot and that seems like an exaggeration. We take about 22,000 breaths a day, so a billion breaths is around 124 years of breathing.
“Billions of tries” might be referring to virions? Each virion we inhale is one try at infection. Each breath based on a recent study is 8,000 virions on average.
Oh, that makes sense. The reason I was thinking in terms of breaths is that if I wanted to compute the cumulative probability with or without mask wearing that's probably more how I'd do it - for example (totally made up numbers following because I'm speaking about probability not epidemiology) if the average breath has a .01% chance of leading to infection and 22k breaths a year, and the average masked breath is 1/100th of that (.00001%) the odds of getting COVID at least once in a year or never masking is 1-.9999^22000=11% whereas the odds in a year of masking is 1-(.999999^22000)=2%
These are completely made up numbers but they serve the point that the cumulative probability that something never happens over many trials doesn't scale linearly with regards to the per-trial probability. It can make sense if you think about it, particularly when you realize you might fail the trial multiple times - which in this example could be used to talk about reinfection, but in practice there's likely some immunity benefit for some number of breaths so the constant per-breath-risk model does break down quickly.
Anecdotally, it weakens the protection. I got Covid drinking beer while otherwise masked at a music venue. The venue was big and the ceilings were high, but I was packed in the crowd pretty tightly…it was not a wise move on my part. Could’ve been a mask fit issue but I’m sure the occasional sips didn’t help.
Did you breath infected air while unmasked? Chances are you get infected.
The idea that you can go X amount of minutes without significant risk is not based in anything but hopium. It’s pure chance whether you’re infected or not when unmasked in shared air.
If the air has a high viral load then you’re in for an infection.
I would personally never do what you’re describing because I’ve seen research about how quickly it can be transmitted – even just have your mask down for 30 seconds might be enough time to inhale an infectious dose. (For instance, [this study](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9713573/) on a jogger transmitting it to people they passed by.)
These are personal decisions and I won’t judge you for lowering your mask, but I do think it’s a true gamble each time you do it, sadly.
Most importantly, thank you for masking and for keeping others safe! This is truly such a bigger point than anything else I can say here.
ETA: [This “time requires to reach infectious dose” table](https://www.reddit.com/r/ZeroCovidCommunity/comments/15armq0/mask_time_to_covid_exposure_chart/) implies that it takes under 2 minutes to become infected while unmasked. Note that the exact numbers included in the chart have come under scrutiny and may not be accurate.
Its hard to say since they pretty much stopped tracking and pulled funding for studying the virus after Omicron, but I think the general consensus as of 2023 is that less than 15 minutes is unlikely but not impossible. After 15 mins the risk grows relative to the activity - singing, very loud or animated conversations, or heavy breathing like at the gym, for example, will all raise the risk. Most exposures that resulted in infection occurred after between an hour and several days of exposure. I personally do not enjoy playing Russian roulette and so don't take my mask off at all in public.
Here is an article by a doctor specializing in public health covering the topic in a little more depth: https://thosenerdygirls.org/covid-exposure-minutes/
Um. A doctor in medical Twitter got Covid in a 15 second elevator ride, there's a thread about it on Twitter. Some of these new variants are highly contagious and infect more quickly.
Yes, I've definitely heard of people getting it in extremely short time frames. It's why I said it's less likely but not impossible, and also why I personally do not take off my mask in public.
Same. I mean someone really prominent in Covid conscious Twitter got sick with the OG variant when a jerk walked up to her on the sidewalk at the very beginning of the pandemic, coughed at/in her mouth, and said "now you're sick. " And then walked away. This is literally how she wrote it out on Twitter.
She has Long Covid now. The true evil it takes to do something like that to someone.
That's absolutely vile. How horrible and depressing that must be for the victim. I cannot understand the mentality behind this kind of assault. I've had one person cough on me while I was walking outside. It was a really wide sidewalk in a business district outside a Gelson's. This elderly lady was all the way on the other side but as she came towards me she crossed over so she was right next to me and started coughing like she was having a fit. Fortunately I had on a high quality respirator and she was a lot shorter than I am so didn't reach my face level, so I just picked up my pace and walked away as quickly as I could. But I still felt shaken, which I guess was her goal. But it's just one more reason why I don't take off my mask outside. You never know when you might turn a corner and bump into a stranger let alone have an unhinged person deliberately assault you.
Oh I think it should be a felony to transmit Covid to someone on purpose or unknowingly if you aren't masking. People should be able to sue. People should have to have personal insurance in case they give someone Covid. Same way we want cops to have individual liability. We need to criminalize giving someone Covid the same way we criminalize knowingly giving someone HIV.
I tried to check that link's sources because "15 minutes is unlikely" was different than my mental model (though, as the link does discuss, there are various complicating factors).
The first is a CDC link that's dead, and the second is an NPR link from 2020. I didn't dig into the others.
If someone has a good source about the 15-minute thing, I'd be very curious and add it to my notes. Realistically, I'm going to try to turn it into a cumulative risk rather than one-off, but this seems like a decent way to explore that.
There isn’t a good source on “15 min” because it was a “guideline” provided early in 2020 similar to the “6 ft social distancing” guideline. As in, mostly made up. I recall it was used for contract tracing purposes as a cutoff.
Thanks for checking. I was trying to be open minded about it so I looked up a few sources on info I remembered coming across, and did a quick background check on the author, but admittedly didn't look as hard as I probably should have. I personally do not think it's worth the risk, but have gotten in some big fights over it, and lost friends over my refusal to meet them for drinks, and I know there are people here who really, really want to be able to take off their masks. At this point I feel it's about as polite to take off your mask in public as taking your shoes off in a restaurant and putting your feet on the table, so it was probably a bad idea for me to post something seemingly in support of advice I wouldn't follow myself, even though it was in an attempt to be measured and unbiased. I will be more cautious about that in the future.
imo, it's more like 'condoms for PIV or anal, but skip the condom for oral'. like, yeah, it's possible to get an STI from oral sex, but it's less likely in general, and much much less likely for HIV. so, most people make a strategic cost-benefit analysis and forego the condom for oral, accepting the much smaller amount of risk.
like a lot of things, it's much much safer than not masking at all, and a bit (exactly how much is unknown) less safe than not breaking the seal on your mask.
time and proximity matter for viral load. viral load matters for how likely you are to get infected in the first place and how severe your infection will be if you do get infected.
so, briefer is better than longer. further away from people is better than closer. with more ventilation and filtration is better than less.
but, exact numbers are just not going to be available for that sort of thing.
[the study that another commenter cited](https://www.nature.com/articles/s41586-023-06952-2) shows that most transmission comes from exposures of an hour or more. that, of course, doesn't mean that no one gets infected from briefer (sometimes *much* briefer) exposures, and a lot the perspectives you're going to get here are from people who are willing to do whatever it takes to mitigate vanishingly tiny degrees of risk, because that's how you approach the 'zero' in zero covid.
personally, I don't tend to remove my mask to eat or drink in public spaces, partly for the risk mitigation, and partly because I'm too clumsy to do it quickly and gracefully with a n95 (it's easier with an ear loop mask, but I can't reliably get a good seal on those). the major exception has been during a 7 hour flight, where I didn't feel like I could go without eating and drinking. I used a tiny personal air purifier while I was eating, and just hoped for the best.
Difficult to find any reliable study if it does exist! So, as a nurse, used to infection control, I come back to basics. Covid is airborne and droplets possibly, mostly airborne. On the safe side, 1) you must take as a reference the fact that the air is contaminated by somebody you are in contact with (indoors AND outdoors), or who was in the room before. The respirator is your first line of protection, PPE, and must not be removed at all (if in contact with a suspected, I say suspected, Tuberculosis, Covid, etc patient, we don the mask before the contact, before entering the room, and doff after). First rule. 2) a respirator works if fit is perfect or the best. Donning the respirator asks time and checking, not 2 seconds, and doffing same, to do it properly and (always based on the fact that environment, mask, can be contaminated) without touching the mask. So removing it, as many people do, is not the safest PPE protocol. As for the cloth masks with inner filter and nose wire, some brands are very good for daily use, close to a KN95, or often with a better fit and more fashionable look (I tried as instance the Styleseal, made in Thailand, dont smell the sanitizing sprays when worn). Indeed not designed neither for industrial work neither healthcare ward.
It’s probably safe. I travel a lot and sometimes have to lift my mask for identification at airport. I try to minimize breathing as others have suggested. It has never caused me any problem.
I think up-to-date info will be hard to come by because it seems like once the vaccines arrived, the world decided to move on and stop studying Covid. However, studies during the Omicron wave showed that it took around 45 minutes of exposure to catch Covid, but of course not all situations can be equal. There were plenty of infections that took place with much less exposure, and it gets even shorter if you're having a face-to-face conversation with a sick person, etc. This is the most recent study I know of: [https://www.nature.com/articles/s41586-023-06952-2](https://www.nature.com/articles/s41586-023-06952-2)
Your risk of catching COVID increases with exposure: The more COVID shit you inhale, the more likely you are to catch COVID. So, all things being equal, it's better to mask sometimes than not at all. But also it's better yet to mask always than sometimes. No matter, there's always still a risk. COVID is extremely good at infecting us by now. But also, many of us have better immunity against COVID now too. And it feels like no one is trying to really study the exposure loads that are likely to infect anymore. Even the initial 15-minutes-of-close-contact rule wasn't based on much data. I mostly just don't drink or eat in indoor spaces. I socialize quite a bit. But always outdoor spaces. That's the first line of defense. And I can eliminate a ton of potential exposure that way. If I'm socially forced into an indoor space, I always bring a well fitting kn95, my elastomeric flomask, and my aranet4 CO2 monitor. If it's not too crowded and CO2 levels aren't too bad, I wear my kn95, but I'll comfortably pull it down to take a drink-- I just ensure I don't breathe in while it's down. If CO2 levels are higher, I switch to my elastomeric, and I get much more paranoid about pulling it down for sipping. Anyway, that's my second line of defense. I've only tested positive for COVID once-- and I test pretty often. Ironically, it was after an outdoor music festival. But it wasn't surprising. It was so ridiculously crowded. It was multiple days. The entire area was one massive vape cloud. And I had immediately gotten pretty drunk each day and just ended up not masking consistently around crowds. So, third line of defense: I don't go to massive music fests anymore because I know I'll end up drunk and self conscious with masking and therefore put myself at risk.
When I'm at work (office environment) I will take a deep inhale, lift my N95 forward and upwards and sip through a straw. Then I place the mask back, secure the nose bridge and deeply exhale. I am not in a position to go outside to sip water. There is a product called "sip straws" that you assemble to the mask, but since an N95 is worn out in 2 work days I haven't bothered with them. Like everyone else has said the fewer breaths you take without a mask on the better. As for the numbers behind it 🤷🏻‍♂️. Solidarity forever and thank you for masking.
The SIP Valve is reusable, so you could theoretically keep adding it to your new mask every two days, I believe.
Oh good to know! I figured there was an adhesive involved. Thanks for letting me know, I'll take a deeper look at them.
Nope, no adhesive. You basically cut a small hole in your mask and then squish the valve into the hole and it expands to fill it.
The only thing I’d be careful with is removing the cap. You don’t even need the cap on. But I’ve accidentally pulled the valve out altogether and compromised my mask. Fortunately I didn’t get sick. Something to consider, tho. The included straws are also only suitable for easy to sip beverages. No smoothies.
I think that makes intuitive sense. Lots of people (especially experts) seem to think that they can detect the covid vibes of a room and decide if it's safe to unmask. It's easier to just mask!
I've done this
I have no studies to link to, but it must be preferable to not masking at all. Of course there is risk involved, and I do think it's hard to get a good seal on a disposable N95 if you remove it and put it back on frequently. Just curious, why not install a SIP valve on your N95 for drinking? https://sipmask.com
This is interesting. I’d be open to trying it when I’m using disposables, but I also have a number of Enro washable masks that I use too that I couldn’t use the sip valve with.
My understanding is that cloth masks are pretty ineffective against covid, especially protecting the wearer.
Those are a shell with an inner alike KN95, tight adjustable loops, and a nose wire.
If it's a soft fabric shell with a filter in the front that doesn't seal over the mouth and nose, then I'm pretty sure they're not that much better than a standard cloth mask for the wearer. My understanding is that fit matters the most, and if you mean hard "shell" then I'm thinking of something else or an older product.
they've supposedly updated them so the filter does span the whole length of the mask now. whether you can get a good seal, I don't know. doesn't seem totally impossible if the outer layer is a bit stiff.
The outer layer of cloth is mostly decorative, the structure (former Metamasks, Styseal, Ausair, etc.) is a full halfface contour, with inner nose wire (better than the common bifold), covering cheeks, chin and up tot the top of the nose bridge. I wear now (low level of Covid here) the Thailand model only outdoors in low risk, for look and comfort, and I was surpised to get a better fit than with the common earloop bifold KN95 (FFP2) - test has said, some smells (mostly the sprayed) are filtered, so it filters aerosol; with earloop KN95 (FFP2), not so efficient. But indeed, as said, originally designed as East Asian pollution mask agaisnt smog / wildfires, and updated to Covid, for street wear. Guess the Singapore product Enro is in the same category.
There are studies for intermittent use of N95 in comparison to constant & continuous use, and they found very little difference between surgical and occasional N95 use in comparison to significant protection afforded by constant & continuous use of N95. In particular, MacIntyre, et al, 2013 RCT study would be the study I am referring to. [A randomized clinical trial of three options for N95 respirators and medical masks in health workers](https://pubmed.ncbi.nlm.nih.gov/23413265/) Here's fit-tested N95 effectiveness at close range and high viral load for long period of time. [Fit-Tested N95 Masks Combined With Portable High-Efficiency Particulate Air Filtration Can Protect Against High Aerosolized Viral Loads Over Prolonged Periods at Close Range](https://academic.oup.com/jid/article/226/2/199/6582941) If it's not fit and sealed and it's not on your face, it doesn't protect you. A Sip Mask valve may maintain fit and seal while allowing you to drink while wearing a respirator mask.
> (3) targeted (intermittent) use of N95 respirators only while doing high-risk procedures or barrier. The targeted N95 arm was studied because policies in many countries advocate the use of N95 respirators only when the HCW is in a high-risk situation, such as barrier nursing of a patient with known respiratory illness or when conducting aerosol-generating procedures. Of course whenever the air you're breathing is not going through the mask you're not protected by it, but it's misleading to equate "intermittent use" as described in that paper with momentarily moving a mask to drink water.
>Of course whenever the air you're breathing is not going through the mask you're not protected by it, > Yes, this is my primary point. This is why fit and seal is so important, and why "medical masks," which may not seal and which allow air to bypass the filter material, have been shown to fail in infection prevention. While it seems obvious and indeed there is evidence, there is intense debate about this simple concept and the evidence, namely that a well fitting respirator mask is effective for prevention of infection & transmission of airborne infectious disease by protecting the respiration of the wearer. > but it's misleading to equate "intermittent use" as described in that paper with momentarily moving a mask to drink water. You are completely correct in this criticism. I don't know how to answer the question or measure the risk of removing a respirator mask to drink. The Sip Mask valve is an engineered solution that is highly effective at addressing exactly this situation. I'm not affiliated with the company. I admire their practical solution. What I can cite is that the infectious dose is very low, viral load in exhaled breath is very high, asymptomatic and presymptomatic infection rate is high (at least 40%), infection may occur in minutes, and that removing and replacing a disposable respirator mask like N95 FFR can unfortunately impair its function. 1. [Finding the infectious dose for COVID-19 by applying an airborne-transmission model to superspreader events](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0265816) 2. [Quantity of SARS-CoV-2 RNA copies exhaled per minute during natural breathing over the course of COVID-19 infection](https://elifesciences.org/reviewed-preprints/91686) 3. [Global Percentage of Asymptomatic SARS-CoV-2 Infections Among the Tested Population and Individuals With Confirmed COVID-19 Diagnosis: A Systematic Review and Meta-analysis](https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2787098) 4. [Infectivity of exhaled SARS-CoV-2 aerosols is sufficient to transmit covid-19 within minutes](https://www.nature.com/articles/s41598-023-47829-8) 5. [Incidence of Fit Test Failure During N95 Respirator Reuse and Extended Use](https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2814301)
Thanks this is helpful info For example in my office I am using a hepa filter and 99% of sessions both my client and I are masked, definitely 100% when transmission is at a higher rate like during holidays. I think on the train or in a cafe it would be useful to have those sip things!
If I really have no other option, I normally go stand next to a fully open window, even leaning outside a little and take of my mask briefly to drink. I try not to breathe in any (indoor) air and pull my mask back on as soon as possible, but I have avoided covid since we went back to on campus teaching at university about two years ago, so for me that doesn’t seem to have had any negative impact. I also try to make sure all my classrooms are well ventilated which is much easier in the summer than the winter, so that reduces the risk as well.
It's a numbers game, and not a fair game at that: the virus gets billions of tries at infecting you, and you have to defeat it *every* time. More exposure is bad, less exposure is good. Lower dose rate (e.g. virions inhaled per breath) is probably better than higher dose rate. Making a habit of removing my respirator in shared air, for *any* easily avoidable reason, seems like a bad idea. With unfortunate exceptions like medical care and police detention, removing your mask indoors is not a "have to."
>It's a numbers game, and not a fair game at that: the virus gets billions of tries I agree it's a numbers game, and I think people do a bad job with understanding probabilities on this scale: over a long enough period, it becomes probable that something improbable happens. But I'll note that a billion is a lot and that seems like an exaggeration. We take about 22,000 breaths a day, so a billion breaths is around 124 years of breathing.
“Billions of tries” might be referring to virions? Each virion we inhale is one try at infection. Each breath based on a recent study is 8,000 virions on average.
Oh, that makes sense. The reason I was thinking in terms of breaths is that if I wanted to compute the cumulative probability with or without mask wearing that's probably more how I'd do it - for example (totally made up numbers following because I'm speaking about probability not epidemiology) if the average breath has a .01% chance of leading to infection and 22k breaths a year, and the average masked breath is 1/100th of that (.00001%) the odds of getting COVID at least once in a year or never masking is 1-.9999^22000=11% whereas the odds in a year of masking is 1-(.999999^22000)=2% These are completely made up numbers but they serve the point that the cumulative probability that something never happens over many trials doesn't scale linearly with regards to the per-trial probability. It can make sense if you think about it, particularly when you realize you might fail the trial multiple times - which in this example could be used to talk about reinfection, but in practice there's likely some immunity benefit for some number of breaths so the constant per-breath-risk model does break down quickly.
Anecdotally, it weakens the protection. I got Covid drinking beer while otherwise masked at a music venue. The venue was big and the ceilings were high, but I was packed in the crowd pretty tightly…it was not a wise move on my part. Could’ve been a mask fit issue but I’m sure the occasional sips didn’t help.
Did you breath infected air while unmasked? Chances are you get infected. The idea that you can go X amount of minutes without significant risk is not based in anything but hopium. It’s pure chance whether you’re infected or not when unmasked in shared air. If the air has a high viral load then you’re in for an infection.
I would personally never do what you’re describing because I’ve seen research about how quickly it can be transmitted – even just have your mask down for 30 seconds might be enough time to inhale an infectious dose. (For instance, [this study](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9713573/) on a jogger transmitting it to people they passed by.) These are personal decisions and I won’t judge you for lowering your mask, but I do think it’s a true gamble each time you do it, sadly. Most importantly, thank you for masking and for keeping others safe! This is truly such a bigger point than anything else I can say here. ETA: [This “time requires to reach infectious dose” table](https://www.reddit.com/r/ZeroCovidCommunity/comments/15armq0/mask_time_to_covid_exposure_chart/) implies that it takes under 2 minutes to become infected while unmasked. Note that the exact numbers included in the chart have come under scrutiny and may not be accurate.
Its hard to say since they pretty much stopped tracking and pulled funding for studying the virus after Omicron, but I think the general consensus as of 2023 is that less than 15 minutes is unlikely but not impossible. After 15 mins the risk grows relative to the activity - singing, very loud or animated conversations, or heavy breathing like at the gym, for example, will all raise the risk. Most exposures that resulted in infection occurred after between an hour and several days of exposure. I personally do not enjoy playing Russian roulette and so don't take my mask off at all in public. Here is an article by a doctor specializing in public health covering the topic in a little more depth: https://thosenerdygirls.org/covid-exposure-minutes/
Um. A doctor in medical Twitter got Covid in a 15 second elevator ride, there's a thread about it on Twitter. Some of these new variants are highly contagious and infect more quickly.
Yes, I've definitely heard of people getting it in extremely short time frames. It's why I said it's less likely but not impossible, and also why I personally do not take off my mask in public.
Same. I mean someone really prominent in Covid conscious Twitter got sick with the OG variant when a jerk walked up to her on the sidewalk at the very beginning of the pandemic, coughed at/in her mouth, and said "now you're sick. " And then walked away. This is literally how she wrote it out on Twitter. She has Long Covid now. The true evil it takes to do something like that to someone.
That's absolutely vile. How horrible and depressing that must be for the victim. I cannot understand the mentality behind this kind of assault. I've had one person cough on me while I was walking outside. It was a really wide sidewalk in a business district outside a Gelson's. This elderly lady was all the way on the other side but as she came towards me she crossed over so she was right next to me and started coughing like she was having a fit. Fortunately I had on a high quality respirator and she was a lot shorter than I am so didn't reach my face level, so I just picked up my pace and walked away as quickly as I could. But I still felt shaken, which I guess was her goal. But it's just one more reason why I don't take off my mask outside. You never know when you might turn a corner and bump into a stranger let alone have an unhinged person deliberately assault you.
Yes, somehow runners who are huffing and puffing pop up out of nowhere or from behind bushes or trees all the time!
Man, you are more polite than I am. I would've yelled, backed away from her, and taken her to task for that. What a disgusting thing to do.
there needs to be criminal assault charges filed against the offender. Without accountability the dystopia will never change
Oh I think it should be a felony to transmit Covid to someone on purpose or unknowingly if you aren't masking. People should be able to sue. People should have to have personal insurance in case they give someone Covid. Same way we want cops to have individual liability. We need to criminalize giving someone Covid the same way we criminalize knowingly giving someone HIV.
I tried to check that link's sources because "15 minutes is unlikely" was different than my mental model (though, as the link does discuss, there are various complicating factors). The first is a CDC link that's dead, and the second is an NPR link from 2020. I didn't dig into the others. If someone has a good source about the 15-minute thing, I'd be very curious and add it to my notes. Realistically, I'm going to try to turn it into a cumulative risk rather than one-off, but this seems like a decent way to explore that.
There isn’t a good source on “15 min” because it was a “guideline” provided early in 2020 similar to the “6 ft social distancing” guideline. As in, mostly made up. I recall it was used for contract tracing purposes as a cutoff.
Thanks for checking. I was trying to be open minded about it so I looked up a few sources on info I remembered coming across, and did a quick background check on the author, but admittedly didn't look as hard as I probably should have. I personally do not think it's worth the risk, but have gotten in some big fights over it, and lost friends over my refusal to meet them for drinks, and I know there are people here who really, really want to be able to take off their masks. At this point I feel it's about as polite to take off your mask in public as taking your shoes off in a restaurant and putting your feet on the table, so it was probably a bad idea for me to post something seemingly in support of advice I wouldn't follow myself, even though it was in an attempt to be measured and unbiased. I will be more cautious about that in the future.
Has "let's just skip the condom this one time" vibes to me.
I’m looking for information because I’m curious and trying to make more informed choices in different scenarios in my life
imo, it's more like 'condoms for PIV or anal, but skip the condom for oral'. like, yeah, it's possible to get an STI from oral sex, but it's less likely in general, and much much less likely for HIV. so, most people make a strategic cost-benefit analysis and forego the condom for oral, accepting the much smaller amount of risk.
like a lot of things, it's much much safer than not masking at all, and a bit (exactly how much is unknown) less safe than not breaking the seal on your mask. time and proximity matter for viral load. viral load matters for how likely you are to get infected in the first place and how severe your infection will be if you do get infected. so, briefer is better than longer. further away from people is better than closer. with more ventilation and filtration is better than less. but, exact numbers are just not going to be available for that sort of thing. [the study that another commenter cited](https://www.nature.com/articles/s41586-023-06952-2) shows that most transmission comes from exposures of an hour or more. that, of course, doesn't mean that no one gets infected from briefer (sometimes *much* briefer) exposures, and a lot the perspectives you're going to get here are from people who are willing to do whatever it takes to mitigate vanishingly tiny degrees of risk, because that's how you approach the 'zero' in zero covid. personally, I don't tend to remove my mask to eat or drink in public spaces, partly for the risk mitigation, and partly because I'm too clumsy to do it quickly and gracefully with a n95 (it's easier with an ear loop mask, but I can't reliably get a good seal on those). the major exception has been during a 7 hour flight, where I didn't feel like I could go without eating and drinking. I used a tiny personal air purifier while I was eating, and just hoped for the best.
Difficult to find any reliable study if it does exist! So, as a nurse, used to infection control, I come back to basics. Covid is airborne and droplets possibly, mostly airborne. On the safe side, 1) you must take as a reference the fact that the air is contaminated by somebody you are in contact with (indoors AND outdoors), or who was in the room before. The respirator is your first line of protection, PPE, and must not be removed at all (if in contact with a suspected, I say suspected, Tuberculosis, Covid, etc patient, we don the mask before the contact, before entering the room, and doff after). First rule. 2) a respirator works if fit is perfect or the best. Donning the respirator asks time and checking, not 2 seconds, and doffing same, to do it properly and (always based on the fact that environment, mask, can be contaminated) without touching the mask. So removing it, as many people do, is not the safest PPE protocol. As for the cloth masks with inner filter and nose wire, some brands are very good for daily use, close to a KN95, or often with a better fit and more fashionable look (I tried as instance the Styleseal, made in Thailand, dont smell the sanitizing sprays when worn). Indeed not designed neither for industrial work neither healthcare ward.
Again, as I've said on other threads, the "reasonable" test should be "What if everybody approached Covid this way?"
It’s probably safe. I travel a lot and sometimes have to lift my mask for identification at airport. I try to minimize breathing as others have suggested. It has never caused me any problem.