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Post by gridley on May 24, 2020 19:10:23 GMT
This is my mask. cambridgemask.com/ It cost 22 British pounds, is washable and has a life expectancy of 350 hours under light pollution scenarios. The filtration system incorporates particulate filtering layers and military grade carbon. Cambridge Masks meets the N99 standard of particulate filtration, providing nearly 100% protection from particulate pollution such as PM2.5 and PM0.3. They claim the finest layer filters out viruses. By the time I ordered mine (end Feb.), they had a backlog delivery date of 2 months. Got it the end of April. I ordered in wave 5. They are now selling Wave 15. Fits like a glove. If it made coffee and did dishes, I'd order more. And when you did a leak test what percentage did you get? Back when I did rescue training I learned why you almost never see a modern firefighter with a beard - they make it impossible to get a proper seal with standard SCBA. We learned to do a rapid leak check *every* time we donned our masks. A vault door doesn't do you much good if you leave the windows open.
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Post by duwayne on May 24, 2020 21:18:10 GMT
McKintire 2015. The study found cotton masks to be 3% effective against a virus. N95 were 44% effective. Sigurdur, I try my best to find the facts on issues so I can determine the best choices. There is a large discrepancy on the reported effectiveness of masks and I’m trying to find an answer. I am always worried that when I comment on things that people will take it personally and that is not my intent. I read the MacIntyre study in light of your comment that “The study found cotton masks to be 3% effective against a virus. N95 were 44% effective.” I’m guessing this conclusion comes from this statement in the report. “Penetration of cloth masks by particles was almost 97% and medical masks 44%. Without reading the details of the report one might come to your conclusion, but this refers to a test where finely ground salt is suspended in air and blown through the material being tested. The number is how much salt is removed. Why this was shown in the summary in a way which could be misinterpreted to mean it was comparing the effectiveness of the masks against a virus made me wonder. So I checked to see who might be behind the study and that is shown at the end. It appears to be 3M who sells medical masks. It is also interesting to see that the cotton masks used in the study were supplied to the users. Apparently 3M is supplying both the cotton masks and the medical masks. And they appear to be low quality cotton masks based on the particle penetration tests although it is possible that it is representative of some cotton masks used by hospital workers in Asia. And these are what are called medical masks which are different from N95 masks. And now to the findings. The study shows an “Attack Rate” comparison for laboratory-confirmed viruses. For the cotton mask group it was 5.4% vs 3.3% for the medical mask group. What is missing is the attack rate is for those without masks. The reason is over 99% of the people in the hospital wear masks and there are so few who don’t that a statistically significant comparison isn’t possible. It is reasonable to conclude that 3M’s medical masks are better than certain cotton masks. I didn’t see anything which justifies the claim that masks, in general, don’t work to some degree against C-19. Nothing seems to be perfect.
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Post by missouriboy on May 24, 2020 21:20:47 GMT
This is my mask. cambridgemask.com/ It cost 22 British pounds, is washable and has a life expectancy of 350 hours under light pollution scenarios. The filtration system incorporates particulate filtering layers and military grade carbon. Cambridge Masks meets the N99 standard of particulate filtration, providing nearly 100% protection from particulate pollution such as PM2.5 and PM0.3. They claim the finest layer filters out viruses. By the time I ordered mine (end Feb.), they had a backlog delivery date of 2 months. Got it the end of April. I ordered in wave 5. They are now selling Wave 15. Fits like a glove. If it made coffee and did dishes, I'd order more. And when you did a leak test what percentage did you get? Back when I did rescue training I learned why you almost never see a modern firefighter with a beard - they make it impossible to get a proper seal with standard SCBA. We learned to do a rapid leak check *every* time we donned our masks. A vault door doesn't do you much good if you leave the windows open. It (a large) seems to tighten up nicely when using the under chin adjustment straps. You can feel the difference when you inhale. That always worked when testing my mask for scuba diving. of course there you have a positive outside pressure and a lack of water in your mask is a sign of success ... other wise you just clear it. Other than that, don't know the proper way to perform a seal test. My wife just laughed and accused me of trying to look stylish for the ER crew.
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Post by duwayne on May 24, 2020 21:40:03 GMT
I’ll give you one reason I wear a mask when I am out near others.
I was at a banquet a couple of years ago and there was a stream of sunlight coming into the banquet-room which highlighted the floating particles of dust in the air. As I looked down the table the through the sunlight I could see the spittle flying from people’s mouths as they were talking. One person looked like a mechanical sprayer. I’m pretty sure a cloth mask would stop spittle.
I feel even better when other people are wearing masks.
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Post by acidohm on May 24, 2020 22:39:25 GMT
And when you did a leak test what percentage did you get? Back when I did rescue training I learned why you almost never see a modern firefighter with a beard - they make it impossible to get a proper seal with standard SCBA. We learned to do a rapid leak check *every* time we donned our masks. A vault door doesn't do you much good if you leave the windows open. It (a large) seems to tighten up nicely when using the under chin adjustment straps. You can feel the difference when you inhale. That always worked when testing my mask for scuba diving. of course there you have a positive outside pressure and a lack of water in your mask is a sign of success ... other wise you just clear it. Other than that, don't know the proper way to perform a seal test. My wife just laughed and accused me of trying to look stylish for the ER crew. I went on a short 'face fit course' couple of weeks ago on the basis it gives you a certificate which may be required to enter a building site at some point. The rubber mask has filters with a 'push close' feature. Push them close, if you cant breath....you have seal. Still had to breath inside an hood with bitter chemical pumped in however, for 5 mins performing different movements. Final test, break seal on mask (fingers pushed between it and chin), suddenly taste awful, mask worked. Regarding effectiveness, we all know the virus is small enough to get past filter. We're not generally encountering live virus particles in the air however, mostly its virus embedded in water droplets emitted from a hole in a face. Then you have to weigh how long those droplets take to evaporate then leaving virus on the filter which suction from your breathing may draw in. Thus, its best to remain away from circumstances that may have virus laden droplets in the air (distancing). If however you need to reduce your perimeter by say, shopping, you have a safety barrier where a mask may prevent a droplet entering your airway....but you need to as quickly as possible re-engage distance, remove/clean mask and swap filters. I wouldnt go to a cv ward and think the mask is preventing infection. Thats why the doctors/nurses should wear face screens too. I'm not sure you are likely to be infected by 1 virus particle either? Anecdotal evidence seems to indicate viral load changes things quite a bit....
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Post by missouriboy on May 24, 2020 22:50:43 GMT
I’ll give you one reason I wear a mask when I am out near others. I was at a banquet a couple of years ago and there was a stream of sunlight coming into the banquet-room which highlighted the floating particles of dust in the air. As I looked down the table in the though the sunlight I could see the spittle flying from people’s mouths as they were talking. One person looked like a mechanical sprayer. I’m pretty sure a cloth mask would stop spittle. I feel even better when other people are wearing masks. I'm a walking vitamin factory. I wear my mask mostly for others. Unless of course I'm wrong. It's becoming quite a cottage industry. All kinds of strange new fashion colors and patterns. I'm waiting for the MAGA20 mask.
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Post by missouriboy on May 24, 2020 22:58:17 GMT
It (a large) seems to tighten up nicely when using the under chin adjustment straps. You can feel the difference when you inhale. That always worked when testing my mask for scuba diving. of course there you have a positive outside pressure and a lack of water in your mask is a sign of success ... other wise you just clear it. Other than that, don't know the proper way to perform a seal test. My wife just laughed and accused me of trying to look stylish for the ER crew. I went on a short 'face fit course' couple of weeks ago on the basis it gives you a certificate which may be required to enter a building site at some point. The rubber mask has filters with a 'push close' feature. Push them close, if you cant breath....you have seal. Still had to breath inside an hood with bitter chemical pumped in however, for 5 mins performing different movements. Final test, break seal on mask (fingers pushed between it and chin), suddenly taste awful, mask worked. Regarding effectiveness, we all know the virus is small enough to get past filter. We're not generally encountering live virus particles in the air however, mostly its virus embedded in water droplets emitted from a hole in a face. Then you have to weigh how long those droplets take to evaporate then leaving virus on the filter which suction from your breathing may draw in. Thus, its best to remain away from circumstances that may have virus laden droplets in the air (distancing). If however you need to reduce your perimeter by say, shopping, you have a safety barrier where a mask may prevent a droplet entering your airway....but you need to as quickly as possible re-engage distance, remove/clean mask and swap filters. I wouldnt go to a cv ward and think the mask is preventing infection. Thats why the doctors/nurses should wear face screens too. I'm not sure you are likely to be infected by 1 virus particle either? Anecdotal evidence seems to indicate viral load changes things quite a bit.... Which would explain why young Chinese doctors in Wuhan were dropping like flies. The canyonlands of Utah and Arizona are looking ever more enticing. Since the Cambridge masks are supposedly designed to military specs, I'm composing a letter asking for info on the carbon filter neutralizing virus.
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Post by sigurdur on May 24, 2020 23:28:42 GMT
McKintire 2015. The study found cotton masks to be 3% effective against a virus. N95 were 44% effective. Sigurdur, I try my best to find the facts on issues so I can determine the best choices. There is a large discrepancy on the reported effectiveness of masks and I’m trying to find an answer. I am always worried that when I comment on things that people will take it personally and that is not my intent. I read the MacIntyre study in light of your comment that “The study found cotton masks to be 3% effective against a virus. N95 were 44% effective.” I’m guessing this conclusion comes from this statement in the report. “Penetration of cloth masks by particles was almost 97% and medical masks 44%. Without reading the details of the report one might come to your conclusion, but this refers to a test where finely ground salt is suspended in air and blown through the material being tested. The number is how much salt is removed. Why this was shown in the summary in a way which could be misinterpreted to mean it was comparing the effectiveness of the masks against a virus made me wonder. So I checked to see who might be behind the study and that is shown at the end. It appears to be 3M who sells medical masks. It is also interesting to see that the cotton masks used in the study were supplied to the users. Apparently 3M is supplying both the cotton masks and the medical masks. And they appear to be low quality cotton masks based on the particle penetration tests although it is possible that it is representative of some cotton masks used by hospital workers in Asia. And these are what are called medical masks which are different from N95 masks. And now to the findings. The study shows an “Attack Rate” comparison for laboratory-confirmed viruses. For the cotton mask group it was 5.4% vs 3.3% for the medical mask group. What is missing is the attack rate is for those without masks. The reason is over 99% of the people in the hospital wear masks and there are so few who don’t that a statistically significant comparison isn’t possible. It is reasonable to conclude that 3M’s medical masks are better than certain cotton masks. I didn’t see anything which justifies the claim that masks, in general, don’t work to some degree against C-19. Nothing seems to be perfect. I never take thoughtful discussion as a personal attack. I don't wear a mask because of my environment. I won't criticize anyone who wants to wear a mask. My wife was a nurse for 42 years. She observes people doing stupid things with their masks. In doing so, any protection is lost for the mask wearer. Someone talked about the seal. When I am in a dusty bin, the lack of seal from common masks is observable. If the bin has any mold, I wear my respirator. The seal is much better. The false sense of security with normal mask users is not justified. They feel like they are doing something, when in reality they are doing very little. A virus is Biohazard level 3 because of the very small size.
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Post by sigurdur on May 25, 2020 2:51:56 GMT
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Post by nautonnier on May 25, 2020 12:42:38 GMT
It all comes down to a person's innate immunity and the viral load taken in. There will be a level of viral load below which the innate immunity will be able to clear the infection; and that may vary dependent on where that viral load initially infects the body. In most cases that is the nose (loss of sense of smell) but it can be the gut - diarrhea, the eyes (conjunctivitis/pink eye), or the lungs. The normally the nose is the infection point up at the top near the sinuses where the virus can multiply and the body start fighting it off - the standard way is for the nose to run as mucus tries to wash the virus particles away and sneezing to blast the virus particles away.
So our mask wearer is sniffling and the occasional muffled sneeze into the mask then takes a deep breath for the next sneeze sucking the virus particles and droplets from the mask deep into the lungs increasing the viral load potentially above the innate immunity level. The sniffles and sneezing turn into aches and lung pain, fever and hospitalization as a fully symptomatic case.
The non mask wearer is sniffling and using tissues and when they sneeze it is into a tissue which is discarded; the breath before the sneeze was ambient non-viral load air. Their sniffles and sneezing abate after 2 or 3 days and they become an 'asymptomatic' case.
The case for masks is not solid - perhaps hanging garlic around your neck to improve social distancing would be as good.
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Post by nautonnier on May 25, 2020 18:25:21 GMT
As yet there has never been a successful vaccine for an RNA virus. Those saying wait for a vaccine may have a long time to wait. " Criticism of the Oxford Coronavirus Vaccine
By Derek Lowe 18 May, 2020
This piece at Forbes by Bill Haseltine has set off a lot of comment – it’s a look at the Oxford group’s vaccine candidate as compared to the SinoVac candidate, and you may recall (background here) that these are the two teams that have separately reported that their vaccines appear to protect rhesus monkeys from infection after exposure to the coronavirus. Haseltine has some criticisms of the Oxford data, and as you will see from that link to his name, his opinions deserve to be taken seriously. So what’s going on? Update: here’s the take on this at BioCentury."blogs.sciencemag.org/pipeline/archives/2020/05/18/criticism-of-the-oxford-coronavirus-vaccine
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Post by nonentropic on May 25, 2020 20:46:00 GMT
My issue with this is which Xmas is this coming.
again it talks about a reduction in symptoms so is it any different from vitamin D of Zn and HQC or some other treatment.
In NZ we live in the binary world of no disease and vaccinated inside the country or pox filled world. looking tricky!!
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Post by nautonnier on May 25, 2020 21:15:53 GMT
My issue with this is which Xmas is this coming. again it talks about a reduction in symptoms so is it any different from vitamin D of Zn and HQC or some other treatment. In NZ we live in the binary world of no disease and vaccinated inside the country or pox filled world. looking tricky!! True And of course the point that all the talking heads never mention how come so few people are infected? We are repeatedly told how badly London or New York City is doing but the number of cases is still a lot less than 3%
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Post by nautonnier on May 26, 2020 0:16:41 GMT
The case fatality rate overall for COVID-19 is less than 1%. If I choose a small area that perhaps has a large long term care facility I could talk the CFR up to 90%. I tend not to believe the medical metrology as the hospitals are trying for more funding which they get from more cases and higher CFR. The 'click bait' media want to talk up the scary problems; the medical statisticians have no filters to catch garbage data and don't care anyway as the worse they can make things the better as they get published by the click bait media. In some areas figures are actually being audited and the COVID-19 fatalities are being significantly reduced.
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Post by nautonnier on May 26, 2020 3:33:11 GMT
The case fatality rate overall for COVID-19 is less than 1%. If I choose a small area that perhaps has a large long term care facility I could talk the CFR up to 90%. I tend not to believe the medical metrology as the hospitals are trying for more funding which they get from more cases and higher CFR. The 'click bait' media want to talk up the scary problems; the medical statisticians have no filters to catch garbage data and don't care anyway as the worse they can make things the better as they get published by the click bait media. In some areas figures are actually being audited and the COVID-19 fatalities are being significantly reduced. The case fatality rate overall for COVID-19 is less than 1%. Source? Several - although everyone is mealy mouthed about it the main problem being nobody really knows the number of infected cases that will only be available when serology tests are correctly carried out. It seems that there are a lot of asymptomatic cases and also many that were sick at home; infected people in these groups make up several times the number that have tested positive and been reported as 'cases' mainly because testing was limited to only those that were definitely symptomatic for COVID-19. From Wikipedia (so it must be right): "As of May 2020, scientific studies indicate an infection fatality rate (IFR) between 0.6% and 0.9% (in countries where the average age and/or obesity rates are relatively quite high).[12][13]" en.wikipedia.org/wiki/Mortality_due_to_COVID-19Honest response: "We look into this question in more detail here and explain that this requires us to know – or estimate – the number of total cases and the final number of deaths for a given infected population. Because these are not known, we discuss what the current data can and can not tell us about the risk of death (here)."ourworldindata.org/coronavirus-usa?country=USA#case-fatality-rateRemember reported cases is really number of positive tests for infection. Serology tests in LA County showed that actual cases were a lot higher than was estimated: " Preliminary results from antibody tests in Los Angeles County indicate that the true number of COVID-19 infections is much higher than the number of confirmed cases there, which implies that the fatality rate is much lower than the official tallies suggest. "The mortality rate now has dropped a lot," Barbara Ferrer, director of the Los Angeles County Department of Public Health, said at a press briefing today. In contrast with the current crude case fatality rate of about 4.5 percent, she said, the study suggests that 0.1 percent to 0.2 percent of people infected by the virus will die, which would make COVID-19 only somewhat more deadly than the seasonal flu." reason.com/2020/04/20/l-a-county-antibody-tests-suggest-the-fatality-rate-for-covid-19-is-much-lower-than-people-feared/
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