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HSSnail  
#1 Posted : 13 July 2020 08:52:47(UTC)
Rank: Super forum user
HSSnail

Can anyone explain to me why you should not wear a face covering with a valve? I have one of these – purchased it months ago just in case and it had finally arrived – behind the valve is a 3 layer filter – so I don’t see how they are more likely to let droplets through that a homemade face covering made out of an old tea shirt. If the valve came straight through I could understand the problem. I am yet to be convinced any face covering will prevent aerosol escape – just good for droplets.

Kate  
#2 Posted : 13 July 2020 10:23:29(UTC)
Rank: Super forum user
Kate

What does the valve appear to do?

HSSnail  
#3 Posted : 13 July 2020 10:32:59(UTC)
Rank: Super forum user
HSSnail

Originally Posted by: Kate Go to Quoted Post

What does the valve appear to do?

Not a lot to be honest LOL. If i blow hard into the mask - no rush of air  or anything through it. I think its designed more as a pollen filter on inhalation.

As i say orderd moths ago "just in case" but now peopel are saying no valves keen to undertsand if this is fact or just people assuming teh valve lets the air out easier.

Edited by user 13 July 2020 10:34:23(UTC)  | Reason: Spelling that even i could spot!

chris.packham  
#4 Posted : 13 July 2020 10:54:14(UTC)
Rank: Super forum user
chris.packham

Where valves are fitted in masks used as PPE the purpose is to allow exhaled air to escape quickly and with minimum resistance. So inhaled air is drawn through the mask itself filtering out dust, or in some cases through filters filtering out chemical vapour, e.g. of a solvent. Exhaled air passes straight out through the valve with no filtration. Thus the mask is of little use in preventing exhalation of infective droplets from being discharged at increase velocity due to the concentration of the exhaled air through the valve.

Hope this answers your question.

HSSnail  
#5 Posted : 13 July 2020 11:08:44(UTC)
Rank: Super forum user
HSSnail

Sorry Chris but we are not discussing PPE we are discussing face covering - 2 totaly different things. we are talking about cloath face coverings with 3 layer filter "pollen" filter behind it. No standared to these, not FFP protection factor - hence my question why are they so bad?

But also you appear to be suggesting that a FFP3 mask issued in a hospital setting with a valve while it may protect the wearer would not protect anyone round them?

A Kurdziel  
#6 Posted : 13 July 2020 11:28:37(UTC)
Rank: Super forum user
A Kurdziel

This is the problem with face coverings: there is no standard associated with them. The only English regs on the matter simply require something that covers you mouth and nose. There is no description of the type of cloth you should be using or how effective it’s meant to be. As said with PPE valves are included in some designs to enable you to exhale more easily but of that means you are (if infected) you are going to be releasing virus into the atmosphere. I can’t see the point a valve with a filter behind it as the point of the valve is to allow for unimpeded exhalation.  Is there any specification with the mask? That should explain what it’s for and basically how it works.

HSSnail  
#7 Posted : 13 July 2020 12:20:30(UTC)
Rank: Super forum user
HSSnail

Originally Posted by: A Kurdziel Go to Quoted Post

  Is there any specification with the mask? That should explain what it’s for and basically how it works.

Specifications? Are you having a laugh? As I say something, I ordered months ago, “just in case” the rules changed. I am under no miscomprehension that it may protect me, its nothing more than a face covering. It Will not supprise you it came from China.  The “filter” is described as a dust/pollen filter, and as I say, it sits behind the valve.

I admit I had not thought about FFP3 with a valve allowing the virus out from the wearer so that one good piece of information I have picked up.  But, these “face coverings” have the filter directly behind the valve – so expelled air does not pass through it any easier than anywhere else on the mask. So I am at a loss to understand how they could be any less effective than a three-layer cloth face covering. Yes, there will be some leakage around the filter, just as there is from the sides of the face covering. Is it yet again a case of people assuming they know how these things work without actually looking at the design?

biker1  
#8 Posted : 13 July 2020 12:54:16(UTC)
Rank: Super forum user
biker1

If it has a three layer pollen filter behind the valve, I'm not sure I understand the purpose of the valve, since it won't allow rapid exhalation, and what's to stop pollen coming in through the rest of the mask if they think a pollen filter is needed? Just sounds like a bit of a gimmick to me, with no obvious purpose.

HSSnail  
#9 Posted : 13 July 2020 13:02:46(UTC)
Rank: Super forum user
HSSnail

I think your right Biker i dont think it serves any purpose - just trying to make a bit of cheep cloth scientific! The problem is with news items, post on this forum  etc sayind "dont wear masks/facecoverings with valves - all we do is mudy the water. I cannot see how this face covering is any less affective that if it did not have the valve - Im also tempted to just stick a patch over it to stop people pointing in the street! (if ever they become mandtory)

Roundtuit  
#10 Posted : 13 July 2020 13:34:14(UTC)
Rank: Super forum user
Roundtuit

https://www.cencenelec.eu/research/CWA/Documents/CWA17553_2020.pdf

3 Description - Community face coverings cover the nose, mouth and chin (coverage area, see Figure 2) and shall not incorporate any inhalation and/or exhalation valve(s).

Trouble is this document was only published in June

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 14/07/2020(UTC), A Kurdziel on 14/07/2020(UTC)
Roundtuit  
#11 Posted : 13 July 2020 13:34:14(UTC)
Rank: Super forum user
Roundtuit

https://www.cencenelec.eu/research/CWA/Documents/CWA17553_2020.pdf

3 Description - Community face coverings cover the nose, mouth and chin (coverage area, see Figure 2) and shall not incorporate any inhalation and/or exhalation valve(s).

Trouble is this document was only published in June

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 14/07/2020(UTC), A Kurdziel on 14/07/2020(UTC)
biker1  
#12 Posted : 13 July 2020 13:37:25(UTC)
Rank: Super forum user
biker1

Given the design of the valve, I don't understand how it will be any less effective than any other mask for the purpose of COVID. I suppose the problem might be if you use it in a setting where face coverings are required (assuming this government ever gets around to enforcing this), where it might be questioned as to effectiveness, although I don't think the average security person is going to appreciate enough about masks to question it.

HSSnail  
#13 Posted : 13 July 2020 14:05:22(UTC)
Rank: Super forum user
HSSnail

Originally Posted by: Roundtuit Go to Quoted Post

https://www.cencenelec.eu/research/CWA/Documents/CWA17553_2020.pdf

3 Description - Community face coverings cover the nose, mouth and chin (coverage area, see Figure 2) and shall not incorporate any inhalation and/or exhalation valve(s).

Trouble is this document was only published in June

thanks Roundtuit had not seen that 1 - so if we were in EU there is guidance - had a quick read and cannot see an explantion as to why a none return inhalation valule would have any effect but never mind, the "guidance says no!"

I agree Biker no less effective than any other face covering - but would people undertstand - think if i end up wearing it i will just cover the valve.

thanks everyone that responded

John Murray  
#14 Posted : 13 July 2020 15:58:32(UTC)
Rank: Forum user
John Murray

"ATTEND YOUR APPOINTMENT WEARING A FACE COVERING"

Attended wearing an N95 (reputable international company)(made in China) facemask. No valve.

Asked to change it to "a recognised facemask"

Given a surgical face-covering (complete with gaps).

I don't think the health service is RPE aware.

thanks 1 user thanked John Murray for this useful post.
RVThompson on 14/07/2020(UTC)
Acorns  
#15 Posted : 14 July 2020 06:19:56(UTC)
Rank: Super forum user
Acorns

Like so many aspects of dealing with CV19 and the enforcement as of 24th July, it's pretty useless.  Face covering can be anything from a full,medical mask to a scar my Aunty knitted me for Christmas.    how a business implements the mask and to what specification is equally vague..  

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RVThompson on 14/07/2020(UTC)
Roundtuit  
#16 Posted : 14 July 2020 08:37:33(UTC)
Rank: Super forum user
Roundtuit

Can someone please explain how face coverings will be effective in shops at preventing the transmission of Covid if the shop workers themselves are exempt from wearing them?

Bear in mind advice is that the covering is there for the benefit of others NOT the wearer.

Given the way order pickers and shelf stackers behave in supermarkets you would would have to assume they have some magic immunity.

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 14/07/2020(UTC), A Kurdziel on 14/07/2020(UTC)
Roundtuit  
#17 Posted : 14 July 2020 08:37:33(UTC)
Rank: Super forum user
Roundtuit

Can someone please explain how face coverings will be effective in shops at preventing the transmission of Covid if the shop workers themselves are exempt from wearing them?

Bear in mind advice is that the covering is there for the benefit of others NOT the wearer.

Given the way order pickers and shelf stackers behave in supermarkets you would would have to assume they have some magic immunity.

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 14/07/2020(UTC), A Kurdziel on 14/07/2020(UTC)
stevedm  
#18 Posted : 16 July 2020 06:05:14(UTC)
Rank: Super forum user
stevedm

Rsmith19801  
#19 Posted : 20 July 2020 09:41:53(UTC)
Rank: New forum user
Rsmith19801

As we all know face coverings will not protect from anything. That is why they are not classed as PPE. It wouldn't be acceptable for a carpenter to cut a piece of wood with a scarf on and expect it to protect him from sawdust yet uk governments are telling people to wear them to protect from a virus. This will actually put the wearer at extra risk as from what I am seeing the general public have no idea how to wear these face coverings and are constantly cross contaminating. My question is where is IOSH in all of this and have they advised UK governments on how dangerous it actually is for people to wear these useless face coverings.

Edited by user 20 July 2020 09:43:46(UTC)  | Reason: Not specified

CptBeaky  
#20 Posted : 20 July 2020 10:01:08(UTC)
Rank: Super forum user
CptBeaky

Originally Posted by: Rsmith19801 Go to Quoted Post
As we all know face coverings will not protect from anything. That is why they are not classed as PPE. It wouldn't be acceptable for a carpenter to cut a piece of wood with a scarf on and expect it to protect him from sawdust yet uk governments are telling people to wear them to protect from a virus. This will actually put the wearer at extra risk as from what I am seeing the general public have no idea how to wear these face coverings and are constantly cross contaminating. My question is where is IOSH in all of this and have they advised UK governments on how dangerous it actually is for people to wear these useless face coverings.

Sorry, but I can't agree with this in the slightest. Face coverings are not meant to protect the wearer, they are there to reduce the risk of the wearer transmitting the virus to other people. The growing scientific evidence is overwhelming in its support of mask (read as face covering) wearing as part of the controls to reduce transmission. The forecasts if these measeures aren't taken are, frankly, terrifying.

One of the main reasons hypothesised as to why the virus hasn't impacted E/SE Asia nearly as much as the rest of the world is that they had exprience from the previous SARS outbreak. As such wearing masks in public has become the norm, and was adopted by people pretty much straight away, without government intevention.

I was skeptical it the start, but as the scientific evidence mounts up I have had to chnage my position. They are not classed as PPE, because they don't protect the wearer, not because they don't protect anybody else. It would be nice if there was an agreed standard, so that we can ensure those being worn are effective, but given the time scale, it is unlikely to happen.

https://covid19.healthdata.org/united-kingdom

The projected deaths graph will give you an indication of the difference they are expected to make.

thanks 4 users thanked CptBeaky for this useful post.
A Kurdziel on 20/07/2020(UTC), flysafe on 20/07/2020(UTC), Kate on 20/07/2020(UTC), nic168 on 21/07/2020(UTC)
chris42  
#21 Posted : 20 July 2020 10:40:11(UTC)
Rank: Super forum user
chris42

Originally Posted by: Brian Hagyard Go to Quoted Post

Can anyone explain to me why you should not wear a face covering with a valve? I have one of these – purchased it months ago just in case and it had finally arrived – behind the valve is a 3 layer filter – so I don’t see how they are more likely to let droplets through that a homemade face covering made out of an old tea shirt. If the valve came straight through I could understand the problem. I am yet to be convinced any face covering will prevent aerosol escape – just good for droplets.

An internet search shows these face coverings to be better quality and it appears the valve filter is designed for pollen/ dust. It appears you breathe both in and out via the valve not the rest of the covering. There was one reference on the web that suggested that these valves and filters was not able to protect anyone user or otherwise from a virus. It also appeared that these valve filters are replaceable, so I guess you could wash the rest of it and periodically replace the valve. The product seemed to be aimed at cyclists etc. So, I expect these valves have the same issue as masks in concentrating your breath, however you seem to indicate otherwise.

Chris

thanks 1 user thanked chris42 for this useful post.
HSSnail on 20/07/2020(UTC)
Roundtuit  
#22 Posted : 20 July 2020 12:49:09(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: CptBeaky Go to Quoted Post
It would be nice if there was an agreed standard, so that we can ensure those being worn are effective, but given the time scale, it is unlikely to happen.

CEN published CWA 17553 Community face coverings - Guide to minimum requirements, methods of testing and use in June.

BSI have also announced intention to start offering a Kite-Mark for products achieving a suitable standard

https://www.bsigroup.com/en-GB/kitemark/product-testing/face-coverings/

Roundtuit  
#23 Posted : 20 July 2020 12:49:09(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: CptBeaky Go to Quoted Post
It would be nice if there was an agreed standard, so that we can ensure those being worn are effective, but given the time scale, it is unlikely to happen.

CEN published CWA 17553 Community face coverings - Guide to minimum requirements, methods of testing and use in June.

BSI have also announced intention to start offering a Kite-Mark for products achieving a suitable standard

https://www.bsigroup.com/en-GB/kitemark/product-testing/face-coverings/

HSSnail  
#24 Posted : 20 July 2020 14:52:17(UTC)
Rank: Super forum user
HSSnail

Originally Posted by: chris42 Go to Quoted Post
Originally Posted by: Brian Hagyard Go to Quoted Post

Can anyone explain to me why you should not wear a face covering with a valve? I have one of these – purchased it months ago just in case and it had finally arrived – behind the valve is a 3 layer filter – so I don’t see how they are more likely to let droplets through that a homemade face covering made out of an old tea shirt. If the valve came straight through I could understand the problem. I am yet to be convinced any face covering will prevent aerosol escape – just good for droplets.

An internet search shows these face coverings to be better quality and it appears the valve filter is designed for pollen/ dust. It appears you breathe both in and out via the valve not the rest of the covering. There was one reference on the web that suggested that these valves and filters was not able to protect anyone user or otherwise from a virus. It also appeared that these valve filters are replaceable, so I guess you could wash the rest of it and periodically replace the valve. The product seemed to be aimed at cyclists etc. So, I expect these valves have the same issue as masks in concentrating your breath, however you seem to indicate otherwise.

Chris

Chris I think you are spot on with that analysis - so i soppose teh question is how good is the filter - probably no good for a virus because of its size. I have decide to take the valve out and stick a patch over it!

thanks 1 user thanked HSSnail for this useful post.
Kate on 20/07/2020(UTC)
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