Jun 24, 2020, 6:06 am
Last edit by: NewbieRunner
Moderator announcement - June 23, 2020:
Flyertalk’s moderators generally take a hands-off approach when it comes to judging the accuracy of members’ statements. While that’s fine for travel debates, a pandemic is clearly a more serious issue.
A meta-analysis of 172 studies that looked at various interventions to prevent the transmission of COVID-19, SARS and MERS from an infected person to people close to them, published in The Lancet on June 1, found that mask wearing significantly reduces the risk of viral transmission.
Given the science, the forum moderators are disallowing any further posts that debate whether or not masks should be worn. Posts that do so will be deleted and members subject to discipline.
Please also note, we do not allow posting of conspiracy theories or racist terms used in place of Covid-19, coronavirus, etc.
- Coronavirus and Travel moderator team
Flyertalk’s moderators generally take a hands-off approach when it comes to judging the accuracy of members’ statements. While that’s fine for travel debates, a pandemic is clearly a more serious issue.
A meta-analysis of 172 studies that looked at various interventions to prevent the transmission of COVID-19, SARS and MERS from an infected person to people close to them, published in The Lancet on June 1, found that mask wearing significantly reduces the risk of viral transmission.
Given the science, the forum moderators are disallowing any further posts that debate whether or not masks should be worn. Posts that do so will be deleted and members subject to discipline.
Please also note, we do not allow posting of conspiracy theories or racist terms used in place of Covid-19, coronavirus, etc.
- Coronavirus and Travel moderator team
Coronavirus and masks/face coverings [Consolidated thread]
Jun 27, 2020, 6:36 pm
#1576
Suspended
Join Date: Feb 2009
Programs: DL, UA, AA, VS
Posts: 5,226
More mask data:
Jun 27, 2020, 7:02 pm
#1577
Join Date: Oct 2001
Location: Germany
Posts: 3,780
The chance that the mask caught enough virus particles to infect you is low (otherwise, everyone without a mask would have been infected a long time ago). The chance that enough of these particles come off the mask, end up on your fingers, migrate from your fingers inside your body and infect you is minuscule. They are (supposedly) tiny particles, so they do not come off from the slightest shake, but are captured inside the filter.
Jun 27, 2020, 7:44 pm
#1578
Join Date: Oct 2014
Location: SoCal
Programs: LH, DL
Posts: 133
In choosing to fly during the pandemic, I made the assumption that anyone around me could have COVID and all have poor health literacy/understanding (especially in regards to mask use).
It only took 10-15 minutes of my time during a whole day of travel.
It only took packing enough santizer.
The care taken is about risk mitigation.
The way I see it, better 95% than 50% (percentages are made up to make a point) risk reduction
Last edited by GMTmin8; Jun 27, 2020 at 8:26 pm Reason: make my point clearer
Jun 27, 2020, 8:55 pm
#1579
Join Date: Dec 2011
Location: DSM
Programs: UA 1K, AA EP, DL PL, HH Dia, Marriott Gld, National Exp
Posts: 720
Of note, I bought these masks for another reason figuring the valve would preclude them for COVID masking. Turns out there are two layers of fabric on the inner surface which create a pocket for the activated charcoal filter. So even tho has valve, there are 3 or 4 (with activated charcoal) layers before breath exhausts through the valve, which is different from the other couple of valve masks I've seen. So, thinking they would be okay as a COVID face covering? Haven't tried them yet as didn't buy for me.
Jun 28, 2020, 6:49 am
#1580
Suspended
Join Date: Jun 2019
Location: Paris & Scotland (Laird), "Suite on the World"
Programs: Hertz platinum, Bonvoy titanium , Delta flying colonel/platinum/MM, retired old men board member
Posts: 592
Put a loose ear loop mask or fabric covering on over the mask that covers the valve exhaust area.
Viral load goes downward onto your hands, keyboards, countertops to be picked up in greater density by others' hands rubbing eyes.
Viral load aerosols are stirred up by your own movements propelling them forward and upward into the air.
Plenty of N95's without valves. or just cover the valve. Very simple. Cannot let viral load free into environment in any direction.
How about running an exhaust tube from the valve down your back and into your pants? That would work.
Viral load in the environment that originates at all in air is to be avoided in tight public spaces. Period. Valves concentrate viral load and propel into air.
ADDENDUM: The masks with valves being sold to US HCW's are all being covered with a secondary paper mask over the valve as part of the mask prolongation protocol.
Viral load goes downward onto your hands, keyboards, countertops to be picked up in greater density by others' hands rubbing eyes.
Viral load aerosols are stirred up by your own movements propelling them forward and upward into the air.
Plenty of N95's without valves. or just cover the valve. Very simple. Cannot let viral load free into environment in any direction.
How about running an exhaust tube from the valve down your back and into your pants? That would work.
Viral load in the environment that originates at all in air is to be avoided in tight public spaces. Period. Valves concentrate viral load and propel into air.
ADDENDUM: The masks with valves being sold to US HCW's are all being covered with a secondary paper mask over the valve as part of the mask prolongation protocol.
The paper mask worn over is used to throw away after usage and not the N95
The problem with this virus is people like above are spreading their beliefs and no data
Jun 28, 2020, 7:10 am
#1581
Join Date: Mar 2005
Programs: Continental Onepass, Hilton, Marriott, USAir and now UA
Posts: 6,423
Again no data. Wearing a surgical mask where do you think the exhaled air goes? Out the sides in all directions.
The paper mask worn over is used to throw away after usage and not the N95
The problem with this virus is people like above are spreading their beliefs and no data
The paper mask worn over is used to throw away after usage and not the N95
The problem with this virus is people like above are spreading their beliefs and no data
I highly recommend the following article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516468/
I copied just one diagram from the article, pasted below.
Even a good N95 mask has sideways and down dispersion. However, when compared to no mask, both do a significantly better job of reducing dispersion of particles. From the discussion portion of the above article
"Surgical masks appeared to be as effective as N95 respirators for respiratory protection of HCWs during the routine care of patients hospitalized with seasonal influenza, [32], [33] and were also as effective in reducing production of infectious aerosols during coughing when worn by influenza patients [34]. The incidence of nosocomial pandemic H1N1 infections appeared to remain low in staff members using surgical masks in a hospital despite admitting substantial numbers of pandemic H1N1 patients [35]. A systematic review has shown that the surgical masks perform similar to the N95 masks in reducing the transmission of respiratory viruses but the latter are more expensive, uncomfortable and irritating to the skin [36]. Recently, Noti et al have shown that about two-thirds of influenza virus particles from a coughing manikin (in a simulated patient room with a high-efficiency particulate air filter) were blocked from entering the mouth by surgical masks or N95 masks that were not properly fitted whereas over 99% of infectious virus particles were blocked by a well-fitted N95 mask on the breathing simulator [37]. Nevertheless it seems more practical for the HCWs to wear the surgical masks as a preventive measure against nosocomial infections in view of its reasonable filtering capacity, better comfort, and higher compliance."
I cannot say it any better
Jun 28, 2020, 7:12 am
#1582
Join Date: May 2010
Location: AVP & PEK
Programs: UA 1K 1.8MM
Posts: 6,337
RE: valves on N95 (and better) masks
Some seem to think that ALL expelled breath exits through the valve, which IS NOT THE CASE.
Only a portion of the expelled breath exits the valve; it is meant to aid in getting rid of heat and moisture.
It would be interesting to know exactly HOW MUCH of the expelled breath exits the valve vs. the filter media and under what conditions.
My best guess is that ~50% of expelled breath exits the valve under normal breathing conditions.
And although I have no scientific data to back me up, I wouldn't be surprised if an N95 (or higher) mask with
a valve is still much better overall than those thin bandanas I keep seeing (especially if they are worn with the wearers' nose exposed!
)
I now [almost] exclusively use P100 masks that have a valve (there is no restriction regarding valves where we are).
Some seem to think that ALL expelled breath exits through the valve, which IS NOT THE CASE.
Only a portion of the expelled breath exits the valve; it is meant to aid in getting rid of heat and moisture.
It would be interesting to know exactly HOW MUCH of the expelled breath exits the valve vs. the filter media and under what conditions.
My best guess is that ~50% of expelled breath exits the valve under normal breathing conditions.
And although I have no scientific data to back me up, I wouldn't be surprised if an N95 (or higher) mask with
a valve is still much better overall than those thin bandanas I keep seeing (especially if they are worn with the wearers' nose exposed!
)I now [almost] exclusively use P100 masks that have a valve (there is no restriction regarding valves where we are).
Jun 28, 2020, 7:19 am
#1583
Join Date: May 2010
Location: AVP & PEK
Programs: UA 1K 1.8MM
Posts: 6,337
..... but I do want to point out that there is plenty of data on air dispersion using both surgical and N95 masks.
I highly recommend the following article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516468/
I copied just one diagram from the article, pasted below.
I highly recommend the following article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516468/
I copied just one diagram from the article, pasted below.
I'd be also interested in the effects of normal breathing.
Question: Have there been studies that delve into transmission of SARS-CoV-2 in regards to coughing vs. normal breathing by an infected person?
Jun 28, 2020, 7:49 am
#1584
Join Date: Jun 2020
Posts: 122
My biggest pet peeve are those people who wear mask covering their mouth only. What is wrong with these people? Urrghh
Jun 28, 2020, 9:30 am
#1585
Join Date: Dec 2018
Location: PHX
Programs: Delta DM, Marriott Lifetime Titanium, HHonrs Diamond
Posts: 1,336
Interesting article, although I would like to point out that it seems to concentrate on COUGHING only, and not NORMAL BREATHING.
I'd be also interested in the effects of normal breathing.
Question: Have there been studies that delve into transmission of SARS-CoV-2 in regards to coughing vs. normal breathing by an infected person?
I'd be also interested in the effects of normal breathing.
Question: Have there been studies that delve into transmission of SARS-CoV-2 in regards to coughing vs. normal breathing by an infected person?
Normal breathing is not a high risk behavior unless you are in very close contact with an infected individual for a significant time.
Talking sheds a lot more viral load.
Talking loudly, shouting, singing sheds way more. (sporting events, loud bars)
Coughing sheds the most with the most velocity.
Here is a summary: https://www.govtech.com/em/emergency...explained.html
(note, the viral load numbers are oversimplified, and I think it takes more to get a true symptomatic infection than stated below based on more recent work, but you can't count your exposure, so....)
Remember the formula: Successful Infection = Exposure to Virus x Time
If a person coughs or sneezes, those 200,000,000 viral particles go everywhere. Some virus hangs in the air, some falls into surfaces, most falls to the ground. So if you are face-to-face with a person, having a conversation, and that person sneezes or coughs straight at you, it's pretty easy to see how it is possible to inhale 1,000 virus particles and become infected.
But even if that cough or sneeze was not directed at you, some infected droplets--the smallest of small--can hang in the air for a few minutes, filling every corner of a modest sized room with infectious viral particles. All you have to do is enter that room within a few minutes of the cough/sneeze and take a few breaths and you have potentially received enough virus to establish an infection.
But with general breathing, 20 copies per minute into the environment, even if every virus ended up in your lungs, you would need 1000 copies divided by 20 copies per minute = 50 minutes.
Speaking increases the release of respiratory droplets about 10 fold; ~200 copies of virus per minute. Again, assuming every virus is inhaled, it would take ~5 minutes of speaking face-to-face to receive the required dose.
The exposure to virus x time formula is the basis of contact tracing. Anyone you spend greater than 10 minutes with in a face-to-face situation is potentially infected. Anyone who shares a space with you (say an office) for an extended period is potentially infected. This is also why it is critical for people who are symptomatic to stay home. Your sneezes and your coughs expel so much virus that you can infect a whole room of people.
If a person coughs or sneezes, those 200,000,000 viral particles go everywhere. Some virus hangs in the air, some falls into surfaces, most falls to the ground. So if you are face-to-face with a person, having a conversation, and that person sneezes or coughs straight at you, it's pretty easy to see how it is possible to inhale 1,000 virus particles and become infected.
But even if that cough or sneeze was not directed at you, some infected droplets--the smallest of small--can hang in the air for a few minutes, filling every corner of a modest sized room with infectious viral particles. All you have to do is enter that room within a few minutes of the cough/sneeze and take a few breaths and you have potentially received enough virus to establish an infection.
But with general breathing, 20 copies per minute into the environment, even if every virus ended up in your lungs, you would need 1000 copies divided by 20 copies per minute = 50 minutes.
Speaking increases the release of respiratory droplets about 10 fold; ~200 copies of virus per minute. Again, assuming every virus is inhaled, it would take ~5 minutes of speaking face-to-face to receive the required dose.
The exposure to virus x time formula is the basis of contact tracing. Anyone you spend greater than 10 minutes with in a face-to-face situation is potentially infected. Anyone who shares a space with you (say an office) for an extended period is potentially infected. This is also why it is critical for people who are symptomatic to stay home. Your sneezes and your coughs expel so much virus that you can infect a whole room of people.
Planes become more problematic when there is more talking, eating, drinking, and alcohol.
Jun 28, 2020, 10:43 am
#1586
Join Date: Apr 2010
Location: VIE
Programs: SAS EBS / *A Silver, Hilton Diamond, Radisson VIP, IHG Platinum
Posts: 3,744
Well, it's usually people who are forced to wear a mask against their will, so they do something that will be accepted by their employer or by authorities, while also allowing them to breathe properly. Cultural norms vary. I've been to places where it's a huge no-no and I've also been to places where it's a standard and most people wear it that way, because they see masks merely as a formality and this is considered an acceptable way to tick the box.
Jun 28, 2020, 10:54 am
#1587
Suspended
Join Date: Jul 2001
Location: Watchlisted by the prejudiced, en route to purgatory
Programs: Just Say No to Fleecing and Blacklisting
Posts: 102,095
For passengers to use the Copenhagen airport, masks are mandatory in the terminal buildings.
Jun 28, 2020, 10:57 am
#1588
A FlyerTalk Posting Legend
Join Date: Aug 2002
Location: NY Metro Area
Programs: AA 2MM Yay!, UA MM, Costco General Member
Posts: 49,025
Now even if 50% of the exhale leaves through the valve, then how much will velocity increase when sending 50% of the volume through only 3% of the mask surface? A12x increase in velocity approximately. Cover the valves until we prove otherwise.
Normal breathing is not a high risk behavior unless you are in very close contact with an infected individual for a significant time.
Talking sheds a lot more viral load.
Talking loudly, shouting, singing sheds way more. (sporting events, loud bars)
Coughing sheds the most with the most velocity.
Here is a summary: https://www.govtech.com/em/emergency...explained.html
(note, the viral load numbers are oversimplified, and I think it takes more to get a true symptomatic infection than stated below based on more recent work, but you can't count your exposure, so....)
And this is why airplanes now are not as risky as one might think. No packed cabins so people are not talking. No alcohol so they are not talking loud. Mandatory masks even if compliance is not perfect, and good, filtered airflow with fresh air exchanges.
Planes become more problematic when there is more talking, eating, drinking, and alcohol.
Normal breathing is not a high risk behavior unless you are in very close contact with an infected individual for a significant time.
Talking sheds a lot more viral load.
Talking loudly, shouting, singing sheds way more. (sporting events, loud bars)
Coughing sheds the most with the most velocity.
Here is a summary: https://www.govtech.com/em/emergency...explained.html
(note, the viral load numbers are oversimplified, and I think it takes more to get a true symptomatic infection than stated below based on more recent work, but you can't count your exposure, so....)
And this is why airplanes now are not as risky as one might think. No packed cabins so people are not talking. No alcohol so they are not talking loud. Mandatory masks even if compliance is not perfect, and good, filtered airflow with fresh air exchanges.
Planes become more problematic when there is more talking, eating, drinking, and alcohol.
Are these numbers without a mask covering the nose and mouth (no valve)?
Jun 28, 2020, 11:29 am
#1589
Join Date: May 2016
Posts: 393
The flip side of this is at least they are wearing a mask over their mouths, where presumably you are going to be dispersing more respiratory droplets further.
Jun 28, 2020, 11:34 am
#1590
Join Date: Dec 2018
Location: PHX
Programs: Delta DM, Marriott Lifetime Titanium, HHonrs Diamond
Posts: 1,336
Well, it's usually people who are forced to wear a mask against their will, so they do something that will be accepted by their employer or by authorities, while also allowing them to breathe properly. Cultural norms vary. I've been to places where it's a huge no-no and I've also been to places where it's a standard and most people wear it that way, because they see masks merely as a formality and this is considered an acceptable way to tick the box.
Also, if masks were "a formality" as you so ignorantly assume, then one would think the in the last 20 years Asians would be at the forefront of designer masks that match wardrobes or otherwise have a dual function as a fashion accessory since they all must comply, so why not make the best of it. Nope, they wear the ugly paper ones by choice because they understand the benefits and the threat at hand, not because it is part of the culture at all. If there was no threat, they would drop them in a heartbeat.