Can wearing N95 mask make you inhale the exhaled carbon dioxide?

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  • #1
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Main Question or Discussion Point

1. Can wearing N95 mask make you inhale the exhaled carbon dioxide?

2. Does it only protect against dusts or also bacteria or viruses? N95 can protect against 3 micron or larger. What are the sizes of bacteria or viruses?

n95.jpg
 
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Answers and Replies

  • #2
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(1) Yes, but it is not really significant: normally you can just ignore this.

(2) It protects against dust and aerosols, possibly originated from coughs/sneezes: it also prevents you touching your mouth with your possibly contaminated (contaminated by bacteria or viruses) hands.
It does not directly protects against small aerosols and bacteria/viruses, since those are smaller than the filtering limit: however, at that size pathogens usually does not survive long enough in the air to cause harm.
 
  • #3
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(1) Yes, but it is not really significant: normally you can just ignore this.

(2) It protects against dust and aerosols, possibly originated from coughs/sneezes: it also prevents you touching your mouth with your possibly contaminated (contaminated by bacteria or viruses) hands.
It does not directly protects against small aerosols and bacteria/viruses, since those are smaller than the filtering limit: however, at that size pathogens usually does not survive long enough in the air to cause harm.

What is your comment about n95 with exhalation valve? It is supposed to suck out carbon dioxide.

n95 with exhalation fan.JPG


How about one with fan built in? Do you think it has benefits?

mask with fan.JPG
 
  • #4
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What is your comment about n95 with exhalation valve? It is supposed to suck out carbon dioxide.
Those valves makes breathing easier, but ~ the same volume of used air remains within the mask anyway and that's the first you will inhale in the next cycle.

Useful if you have glasses: prevents them got moist with exhalation.

How about one with fan built in? Do you think it has benefits?
Looks cool (?), but that's all o0)
 
  • #5
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Those valves makes breathing easier, but ~ the same volume of used air remains within the mask anyway and that's the first you will inhale in the next cycle.

Useful if you have glasses: prevents them got moist with exhalation.
Why do eyeglasses get moist with exhalation if there is no exhalation valve? Is it not the exhaled air passes through the filter and it goes straight just like in normal breathing?

Looks cool (?), but that's all o0)
 
  • #6
russ_watters
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2. Does it only protect against dusts or also bacteria or viruses? N95 can protect against 3 micron or larger. What are the sizes of bacteria or viruses?
The statement isn't correct. See here:
https://www.ncbi.nlm.nih.gov/pubmed/9487666
https://www.ncbi.nlm.nih.gov/pubmed/16490606
https://www.ncbi.nlm.nih.gov/pubmed/24011377

Yes, these filters will stop bacteria and at least some viruses (up to about .4 micron).
Why do eyeglasses get moist with exhalation if there is no exhalation valve? Is it not the exhaled air passes through the filter and it goes straight just like in normal breathing?
When you exhale, the air pressure pushes the mask away from your face and the air escapes through the sides, bottom and top; including up behind your glasses.
 
  • #7
BillTre
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To really be sure, in biology labs, a 0.1 micron filter is used to exclude viruses in fluid filtering and (I think) in hepa filtered laminar flow hoods.

Most of these kinds of masks are to prevent small particles from being inhaled in to the lungs.
In a surgical setting (@Laroxe ?), the maskes should ideally prevent things (like bacteria) from going out on to the patient. The way the mask is held onto the head, in the pictured cases is not tight and as @russ_watters said air can easily leak out when exhaled, avoiding filtration.
 
  • #8
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  • #9
BillTre
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So the n95 with exhalation valve has advantage?
It will make exhalation easier as there will be less resistance to work against. Depending on the valve, it might direct your exhalation away from your glasses.
It will short circuit any filtration of the exhalation, but these things are mostly made to keep things out of your lungs (Personal Protection Equipment or PPE).
 
  • #10
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It will make exhalation easier as there will be less resistance to work against. Depending on the valve, it might direct your exhalation away from your glasses.
It will short circuit any filtration of the exhalation, but these things are mostly made to keep things out of your lungs (Personal Protection Equipment or PPE).
The one with built in electronic fan can facilitate it? Do you think it's useful, see earlier picture.
 
  • #11
BillTre
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It would be best to have a link to that product to look at.
It may continuously draw air in through the filter, making inhalation easier and not having left over exhaled air to re breath in, but the product info should explain it.
Personally, it looks not very useful to me, but it may be for some special purpose.
 
  • #12
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It would be best to have a link to that product to look at.
It may continuously draw air in through the filter, making inhalation easier and not having left over exhaled air to re breath in, but the product info should explain it.
Personally, it looks not very useful to me, but it may be for some special purpose.
https://www.airplus-family.com/our-innovation-story-air-n95-masks/

what you think?
 
  • #13
BillTre
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what you think?
To quote the link:
AIR+ attachable fan are engineered to expel exhalation according to our respiratory cycle. Proven to reduce trapped heat, carbon dioxide and moisture within the mask, AIR+ attachable fan delivers enhanced comfort to your mask-wearing experience.
It seems to remove exhale air not forced out from behind the mask at the end of an exhalation.
 
  • #14
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To quote the link:

It seems to remove exhale air not forced out from behind the mask at the end of an exhalation.
So for normal or typical N95, the exhale air is forced out from behind the mask? (and in the product above, it doesn't?
 
  • #15
BillTre
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Without the fan, the volume behind the mask after exhaling would remain there until inhaled in the next breath.
In between breaths, the fan would (presumably) blow out air (while causing fresh air to come inthrough the mask filter, thus you would have resh air to breath in.
 
  • #16
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i
Without the fan, the volume behind the mask after exhaling would remain there until inhaled in the next breath.
In between breaths, the fan would (presumably) blow out air (while causing fresh air to come inthrough the mask filter, thus you would have resh air to breath in.
But can't exhale air easily pass through the mask fibers? It is supposed to filter 3 microns. What is the size of the exhaled air? Why can't it easily pass through the fibers?
 
  • #17
BillTre
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It won't go out the mask unless forced out. Unless the mask is completely up tight against your face, there will be a residual volume of air behind the mask. When your lungs were pushing air out, the air behind the mask is forced out, but with out that lung pressure driving the air movement at the end of exhalation, the air behind the mask will stay behind the mask. Over longer time periods it could diffuse through the mask and equilibrate with the outside the mask atmosphere, but that would take longer than a breathing cycle.

Re-breathing the amount of left over air behind the mask is probably not at all significant to your metabolism. You are also re-breathing air in your trachea and other breathing tubes (between your lungs and mouth/nose). When you go snokleing, you will breath in some air in the snorkle tube that you just exhaled. Same kind of thing.
 
  • #18
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It won't go out the mask unless forced out. Unless the mask is completely up tight against your face, there will be a residual volume of air behind the mask. When your lungs were pushing air out, the air behind the mask is forced out, but with out that lung pressure driving the air movement at the end of exhalation, the air behind the mask will stay behind the mask. Over longer time periods it could diffuse through the mask and equilibrate with the outside the mask atmosphere, but that would take longer than a breathing cycle.

Re-breathing the amount of left over air behind the mask is probably not at all significant to your metabolism. You are also re-breathing air in your trachea and other breathing tubes (between your lungs and mouth/nose). When you go snokleing, you will breath in some air in the snorkle tube that you just exhaled. Same kind of thing.
Ok. What air mask is suggested by CDC or WHO for used against coronovirus?

I'm talking of general daily use and not full fledged biohazard level 4 suit like:

biohazard suit.JPG
 
  • #19
BillTre
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The most important thing for good mask function is a good tight seal with your face. The one in the picture of the guy in yellow is great. I use them if I am sanding plaster, which makes lots of small particles. They work really well. The more loosely the mask is held on your face, the more poorly they will work. HAIR+ attachable fan are engineered to expel exhalation according to our respiratory cycle. Proven to reduce trapped heat, carbon dioxide and moisture within the mask, AIR+ attachable fan delivers enhanced comfort to your mask-wearing experience. However, these are cheaper and less intrusive. You have to make the choice appropriate to the unique sets of conditions and challenges you are dealing with.

As far a the kind of mask fliter material (N95 or some other kind), I would look at the links @russ_watters posted above.
The guy in yellow's mask can come in N95 as well as those that are essentially pieces of paper held in place by a rubber band. If they leak when you inhale, it doesn't matter how good the filter material is.
 
  • #20
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The most important thing for good mask function is a good tight seal with your face. The one in the picture of the guy in yellow is great. I use them if I am sanding plaster, which makes lots of small particles. They work really well. The more loosely the mask is held on your face, the more poorly they will work. HAIR+ attachable fan are engineered to expel exhalation according to our respiratory cycle. Proven to reduce trapped heat, carbon dioxide and moisture within the mask, AIR+ attachable fan delivers enhanced comfort to your mask-wearing experience. However, these are cheaper and less intrusive. You have to make the choice appropriate to the unique sets of conditions and challenges you are dealing with.

As far a the kind of mask fliter material (N95 or some other kind), I would look at the links @russ_watters posted above.
The guy in yellow's mask can come in N95 as well as those that are essentially pieces of paper held in place by a rubber band. If they leak when you inhale, it doesn't matter how good the filter material is.
N95 are meant to protect against dusts and pm2.5 particles of 2.5 microns or larger. What is the list or kind of mask by CDC for use against the coronavirus which might reach epidemic proportion in coming weeks or months?
 
  • #21
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What is the list or kind of mask by CDC for use against the coronavirus which might reach epidemic proportion in coming weeks or months?
N95 from here:
The Centers for Disease Control and Prevention (CDC) does not generally recommend facemasks and respirators for use in home or community settings. However, they may be appropriate for persons at increased risk of severe illness from influenza or other respiratory diseases. Please consult with your health care provider for more information about when to use N95 Respirators at home or in the community.
FDA has cleared the following N95 respirators for use by the general public in public health medical emergencies:

  • 3M™ Particulate Respirator 8670F
  • 3M™ Particulate Respirator 8612F
  • Pasture Tm F550G Respirator
  • Pasture Tm A520G Respirator
These devices are labeled "NOT for occupational use.”
Surgical masks (not the cosmetic but medical type) provides less protection but they are also less inconvenient.

Also, you have to be clear about the difference of 'no recommendation exists' and 'not recommended', which is a kind of negative recommendation. This case is the former, I think.

Also, as far as I know usage of surgical/face masks is a recommendation for patients (after the first cough/sneeze, at least) and healthcare personnel (at least after the first sneeze of the patient) during flu (or other respiratory illness) season.

One more: visiting healthcare settings during flu (or other respiratory illness) season is the very case of 'persons at increased risk of severe illness from influenza or other respiratory diseases' from above. It is fine to go with a mask without waiting for the first sneeze.
 
  • #22
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N95 from here:

Surgical masks (not the cosmetic but medical type) provides less protection but they are also less inconvenient.

Also, you have to be clear about the difference of 'no recommendation exists' and 'not recommended', which is a kind of negative recommendation. This case is the former, I think.

Also, as far as I know usage of surgical/face masks is a recommendation for patients (after the first cough/sneeze, at least) and healthcare personnel (at least after the first sneeze of the patient) during flu (or other respiratory illness) season.

One more: visiting healthcare settings during flu (or other respiratory illness) season is the very case of 'persons at increased risk of severe illness from influenza or other respiratory diseases' from above. It is fine to go with a mask without waiting for the first sneeze.
Are these that use n95 cartridges more effective?

respirators.JPG
 
  • #23
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Are these that use n95 cartridges more effective?

View attachment 256027
Ain't you a teeeny bit overdoin' this ? o_O
It's still not the zombie apocalypse, you know...
 
  • #24
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Ain't you a teeeny bit overdoin' this ? o_O
It's still not the zombie apocalypse, you know...
Haven't you read the headlines lately? Tune into CNN now or check its website.

Right now, all n95 masks are out of stock in the city. I'm just wondering how the above bigger glass masks perform (what do you think?), in case those are the only stocks left. Also remember BillTre used one of those in his home.
 
  • #25
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Haven't you read the headlines lately?
As far as I know yesterday the suspected cases in the USA was three, and some others (a dozen, maybe?) are monitored.
However, the reaction there seems to be more hysteric than in China where it is already pandemic (?) or close.

Just pipe down a bit. At this point what you should be more worried about is flu and cold.
Also, you can be very sure that business will not skip such a wonderful opportunity and stocks will be replenished in days.
 

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