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prove me wrong.... coronavirus is not airborne
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mac



Joined: 07 Mar 1999
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Location: Berkeley, California

PostPosted: Fri Dec 11, 2020 4:18 pm    Post subject: Reply with quote

Well, this seems pretty definitive.

https://www.washingtonpost.com/investigations/2020/12/11/coronavirus-airborne-video-infrared-spread/?arc404=true&utm_campaign=wp_post_most&utm_medium=email&utm_source=newsletter&wpisrc=nl_most&carta-url=https%3A%2F%2Fs2.washingtonpost.com%2Fcar-ln-tr%2F2d7a6cf%2F5fd3a6779d2fda0efb85416f%2F5976d6ccade4e26514ba9956%2F9%2F68%2F5fd3a6779d2fda0efb85416f
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real-human



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PostPosted: Sun Dec 13, 2020 9:57 am    Post subject: Reply with quote

mac wrote:
Well, this seems pretty definitive.

https://www.washingtonpost.com/investigations/2020/12/11/coronavirus-airborne-video-infrared-spread/?arc404=true&utm_campaign=wp_post_most&utm_medium=email&utm_source=newsletter&wpisrc=nl_most&carta-url=https%3A%2F%2Fs2.washingtonpost.com%2Fcar-ln-tr%2F2d7a6cf%2F5fd3a6779d2fda0efb85416f%2F5976d6ccade4e26514ba9956%2F9%2F68%2F5fd3a6779d2fda0efb85416f


but note they do not show that you are infected with it in the air. We know there are horrible things in all air samples, but it takes a certain amount before you can catch them. No study has ever shown covid 19 airborne can infect,

we know that TB a bacteria can infect airborne and is so contagious that it has a R(0) of 11-13. where at best Covid is 1-3.


Peer reviewed and posted on this thread, ya you can sit next to an infected unmasked person for a 2 hour average train ride in a bullet train and the direction you are breathing to the person sitting in front of you the risk is half that of sitting next to the person. And the person sitting next to you has a 3.6% chance of being infected and the one in front half of that.

again these are infected people who are breathing as shown. average 2 hour ride. person the direction of the breathing ie airflow projection is half of the person sitting next to them.

In that study the sample size was tracing about 400 or 600 infected riders and contact tracing 70,000 sitting near. That is a very valid real life showing it is not airborn as the WHO has said to date there is ZERO evidence presented that would make them change their statement that it is not airborne.

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PostPosted: Wed Dec 16, 2020 12:58 pm    Post subject: Reply with quote

you do not breath on a door handle.

not peer reviewed yet

https://www.medrxiv.org/content/10.1101/2020.12.10.20247171v1  

Environmental monitoring shows SARS-CoV-2 contamination of surfaces in food plants  


 
Quote:

• [Preprint, not peer-reviewed] In a study collecting 22,643 surface samples from 116 food processing facilities in the US from Mar 17 to Sep 3, 2020, 1.2% of the total samples tested positive for SARS-CoV-2 by PCR. 62 (53%) facilities had at least one sample positive for SARS-CoV-2. Among the positive samples, 33% were found on doorknobs/handles. The authors suggest that environmental surveillance for SARS-CoV-2 may aid in identifying workplaces with SARS-CoV-2 transmission.


Ming et al. (Dec 11, 2020). Environmental Monitoring Shows SARS-CoV-2 Contamination of Surfaces in Food Plants. Pre-print downloaded Dec 14 from https://doi.org/10.1101/2020.12.10.20247171


Quote:
Highlights

Environmental contamination by SARS-CoV-2 virus was detected in food plants

Out of 22,643 environmental swabs, 278 (1.23%) were positive for SARS-CoV-2

Frequently touched surfaces had the most contamination

Surface testing for SARS-CoV-2 may indicate presence of asymptomatic carriers
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mac



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PostPosted: Thu Dec 17, 2020 4:46 pm    Post subject: Reply with quote

Quote:

By Benjamin Wallace-Wells

December 17, 2020
A Biogen sign outside of a glass office building.
A Biogen conference in February seemed like a normal event in the modern world. Eight months later, it had led to a quarter-million coronavirus infections.Photograph by Cody O'Loughlin / NYT / Redux
Facts are hard-won in medical science. To establish that one drug is slightly more effective than another might require hundreds of millions of dollars and a years-long trial among thousands of patients. A year ago, when the coronavirus first appeared, scientists knew virtually nothing about it—whom it might affect, how it spread. In March, when the pandemic forced much of the United States into lockdown, there was no consensus about whether people should wear masks; more fundamentally, there was no consensus about whether the virus was spread by droplets or whether it was airborne. Such facts are so hard to establish because they need to be sturdy enough to support a person’s life.

Last Friday morning, I received a phone alert from the Boston Globe: epidemiologists and genomicists had traced covid-19 infections at a Boston biotech conference in late February and estimated that, by October, the conference had led to between some two and three hundred thousand cases, across twenty-nine states and multiple countries. That was the headline, but the substance of the paper, which appeared in Science, was a careful tracking of a mutation of the coronavirus that had appeared among patients who were infected at the conference, which was held by the drug company Biogen, and then moved through Massachusetts and to other states and continents. These are the kind of empirical facts that have been in short supply, and they provide a glimpse of not just a cluster of infections isolated in place and time but a branch of the pandemic as it spread through the world and through the year.

Read The New Yorker’s complete news coverage and analysis of the coronavirus pandemic.
By 4 p.m. Friday, I was on a video call with the two lead authors of the paper, Jacob Lemieux, an infectious-disease physician and postdoctoral researcher at Harvard, and Bronwyn MacInnis, the director of pathogen genomic surveillance at the Broad Institute’s Infectious Disease and Microbiome Program. They looked a little worn out, having spent the day trying to explain a paper about the processes of superspreading to reporters who were primarily interested in how many infections could be traced to the conference. “In the initial version of the paper, we didn’t have a number—we didn’t want to go there,” Lemieux said. “People kept asking, ‘How many cases? How many cases?’ So we did our best, as scientists, to flesh this out.” Lemieux noted that, though the paper offered an estimate of the number of infections, it also included half a paragraph of caveats, most of which acknowledged the incompleteness of databases of coronavirus genomes and the imperfections of the calculations, including Lemieux and MacInnis’s, that rely on them. “What we’re trying to point out is it’s a big number,” Lemieux said. “It’s bigger than we would have expected.”

From one point of view, an end to the coronavirus seems near. This week, the first doses of the vaccine were administered at the hospital where Lemieux works and at many others around the country. From another point of view, we are just beginning to see clearly how high the stakes have been, both in every public gathering and in every effort to regulate them. Although researchers have suspected since early in the pandemic that the virus’s spread has been shaped by “superspreader events,” in which some branches of the disease spread much more explosively than others, no one knows whether the cause is the viral load in a host or the situations in which a host encounters other people—or some combination of the two. Nothing about the Biogen conference was unique, Lemieux emphasized: a hundred and seventy-five people from several countries gathered in a hotel at the end of February, before anyone wore masks. It was just a normal event in the course of the modern world. Eight months later, that meeting had led to the infections of a quarter of a million people, give or take. MacInnis tilted her head back and looked straight upward while she thought through what she wanted to say. She said, “It certainly captures my imagination.”
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real-human



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PostPosted: Thu Dec 17, 2020 11:07 pm    Post subject: Reply with quote

https://www.atsjournals.org/doi/pdf/10.1164/rccm.202006-2136LE


SARS-CoV-2 Detected on Environmental Fomites for both Asymptomatic and
Symptomatic COVID-19 Patients


Quote:
• SARS-CoV-2 RNA was detected on surfaces in the rooms of both symptomatic and asymptomatic SARS-CoV-2 infected patients in a hospital in Shenzen, China. Among asymptomatic patients, samples from squat toilets showed the highest positivity rate, followed by samples related to mouth or nose contact (e.g. water cup, straw), and then samples from inside masks worn by the patients. A significantly higher proportion of samples were positive from the rooms of patients with higher viral load among patients who were symptomatic, while a similar but nonsignificant relationship was observed among patients who were asymptomatic. All samples collected from surfaces following disinfection with alcohol or chlorine-containing solutions were negative in both symptomatic and asymptomatic groups.

Yang et al. (Dec 16, 2020). SARS-CoV-2 Detected on Environmental Fomites for Both Asymptomatic and Symptomatic COVID-19 Patients. American Journal of Respiratory and Critical Care Medicine. https://doi.org/10.1164/rccm.202006-2136LE

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real-human



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PostPosted: Thu Dec 17, 2020 11:13 pm    Post subject: Reply with quote

mac wrote:
Quote:

By Benjamin Wallace-Wells

December 17, 2020
A Biogen sign outside of a glass office building.
A Biogen conference in February seemed like a normal event in the modern world. Eight months later, it had led to a quarter-million coronavirus infections.Photograph by Cody O'Loughlin / NYT / Redux
Facts are hard-won in medical science. To establish that one drug is slightly more effective than another might require hundreds of millions of dollars and a years-long trial among thousands of patients. A year ago, when the coronavirus first appeared, scientists knew virtually nothing about it—whom it might affect, how it spread. In March, when the pandemic forced much of the United States into lockdown, there was no consensus about whether people should wear masks; more fundamentally, there was no consensus about whether the virus was spread by droplets or whether it was airborne. Such facts are so hard to establish because they need to be sturdy enough to support a person’s life.

Last Friday morning, I received a phone alert from the Boston Globe: epidemiologists and genomicists had traced covid-19 infections at a Boston biotech conference in late February and estimated that, by October, the conference had led to between some two and three hundred thousand cases, across twenty-nine states and multiple countries. That was the headline, but the substance of the paper, which appeared in Science, was a careful tracking of a mutation of the coronavirus that had appeared among patients who were infected at the conference, which was held by the drug company Biogen, and then moved through Massachusetts and to other states and continents. These are the kind of empirical facts that have been in short supply, and they provide a glimpse of not just a cluster of infections isolated in place and time but a branch of the pandemic as it spread through the world and through the year.

Read The New Yorker’s complete news coverage and analysis of the coronavirus pandemic.
By 4 p.m. Friday, I was on a video call with the two lead authors of the paper, Jacob Lemieux, an infectious-disease physician and postdoctoral researcher at Harvard, and Bronwyn MacInnis, the director of pathogen genomic surveillance at the Broad Institute’s Infectious Disease and Microbiome Program. They looked a little worn out, having spent the day trying to explain a paper about the processes of superspreading to reporters who were primarily interested in how many infections could be traced to the conference. “In the initial version of the paper, we didn’t have a number—we didn’t want to go there,” Lemieux said. “People kept asking, ‘How many cases? How many cases?’ So we did our best, as scientists, to flesh this out.” Lemieux noted that, though the paper offered an estimate of the number of infections, it also included half a paragraph of caveats, most of which acknowledged the incompleteness of databases of coronavirus genomes and the imperfections of the calculations, including Lemieux and MacInnis’s, that rely on them. “What we’re trying to point out is it’s a big number,” Lemieux said. “It’s bigger than we would have expected.”

From one point of view, an end to the coronavirus seems near. This week, the first doses of the vaccine were administered at the hospital where Lemieux works and at many others around the country. From another point of view, we are just beginning to see clearly how high the stakes have been, both in every public gathering and in every effort to regulate them. Although researchers have suspected since early in the pandemic that the virus’s spread has been shaped by “superspreader events,” in which some branches of the disease spread much more explosively than others, no one knows whether the cause is the viral load in a host or the situations in which a host encounters other people—or some combination of the two. Nothing about the Biogen conference was unique, Lemieux emphasized: a hundred and seventy-five people from several countries gathered in a hotel at the end of February, before anyone wore masks. It was just a normal event in the course of the modern world. Eight months later, that meeting had led to the infections of a quarter of a million people, give or take. MacInnis tilted her head back and looked straight upward while she thought through what she wanted to say. She said, “It certainly captures my imagination.”


Ya they admit they are clueless... they do not even talk about if they had shared a coffee pot, a buffet arrangement of any kind, if shared bathroom or open close the door to enter or go to the bathroom. Did they shake hands upon meeting as customary at that time, and in departing.

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PostPosted: Tue Dec 22, 2020 6:45 pm    Post subject: Reply with quote

here is a write up, they found basically no proof at all being airborne. They even used the stupid one like the choir which no one discussed the chairs they moved or the breakroom where thy ate and could have passed around drinks or food. Or touching the doorknob to enter ar use the bathroom or sink.

go to the link as the readbaility is much better.

https://depts.washington.edu/pandemicalliance/wordpress/wp-content/uploads/2020/12/Summary-Ventilation_2020_12_21-003.pdf?mkt_tok=eyJpIjoiTURObE9EVmxNR00wTjJNMCIsInQiOiJxNFFKbjhXWXl6Q0pDZUJSclBWNVl0dndManBWVThVV0J2Y2FQT2c5WXk1WU1oWmNTSDdzQVFkZUNYYVwvZzJHY3dEUmJxY0NDRmp4MjZFOUR3SkRpRmVuTWFCNVluNFgwMUpLczNNU0RJcjhrdGxSMVZkNUpQbHNFblRTVWhWcXQifQ%3D%3D
Summary of Evidence Related to Indoor Ventilation to Reduce SARS-CoV-2 Transmission
December 21, 2020
COVID-19 Literature Report Team:
Lorenzo Tolentino MPH , Jennifer M. Ross MD MPH, Jessie Seiler MPH,
Wenwen Jiang MPH, Sherrilynne Fuller PhD FACMI, Dylan Green MPH, Diana M. Tordoff MPH, Diana
Louden MLib, Alison Drake PhD MPH, Will Hahn MD, and Brandon L. Guthrie PhD
Mitigation of SARS-CoV-2 transmission in indoor spaces is crucial, especially during the winter season
when activities are mostly held in enclosed indoor environments. Understanding SARS-CoV-2 transmission
mechanisms relating to ventilation of indoor air and what evidence-based environmental measures are
available will be key to infection control. This document is a brief summary of published evidence on
SARS-CoV-2 transmission mechanisms that relate to ventilation of indoor spaces and ventilation
standards/best practices for minimizing spread. References are mainly drawn from the COVID-19
Literature Report (Lit Rep) team database and guidelines published by the CDC. References that appeared
in the daily Lit Rep are marked with an asterisk*, and the summary is shown in the annotated
bibliography below.
Executive Summary of Ventilation and SARS-CoV-2
• Most evidence suggests SARS-CoV-2 is largely transmitted through close contact and larger
respiratory droplets. A small number of studies have isolated viable virus from air samples in
lab and clinical settings and SARS-CoV-2 airborne transmission beyond 6 feet has only been
observed in poorly ventilated and crowded indoor spaces.
• While SARS-CoV-2 RNA has been detected in heating, ventilation, and air conditioning (HVAC)
systems, viable virus was not isolated. There has been no documented evidence of SARS-CoV2 transmission occurring through HVAC systems.
• Ventilation standards/best practices to reduce risk of SARS-CoV-2 transmission primarily
include methods to decrease concentrations of aerosols that may carry infectious virus either
through filtration of indoor air or circulation of cleaner air from outside.
• Ventilation standards/best practices alone are not enough to mitigate SARS-CoV-2
transmission. They should only be implemented in conjunction with infection control
measures that more directly address SARS-CoV-2 primary modes of transmission, such as
reducing building occupancy to facilitate physical distancing, mask wearing, surface
disinfection, and handwashing.
SARS-CoV-2 Transmission related to Ventilation
Note: Some of the evidence covered here can also be found in the CDC brief on SARS-CoV-2 and Potential
Airborne Transmission.
Aerosol Transmission
• Particles ejected when an infectious person sneezes, coughs, sings, or breathes form a spectrum
of respiratory droplets and aerosols.
Updated 12/21/2020
o Respiratory droplets are large droplets (>5 μm in diameter) that settle more quickly on
surrounding surfaces. They are responsible for droplet transmission, which occurs when
a person in close contact (within about 6 feet) inhales these droplets.
o Aerosols (<5 μm in diameter) are smaller, lighter particles which can remain airborne for
much longer and can be carried farther by airflow and wind currents. They are responsible
for airborne transmission, which occurs when a person inhales these particles.
• The SARS-CoV-2 virus, which is around 0.1 μm, generally does not travel through the air by itself.
Potentially infectious virus (based on replication in cell culture) has been isolated from air samples
as well as from surfaces on which respiratory droplets have deposited,
1,2* indicating that particles
of varying size can be laden with infectious virus.
• While other coronaviruses are more likely to be present in aerosols than in larger respiratory
droplets,
3 the exact distribution of the SARS-CoV-2 across the range of different-sized particles is
unknown.
No substantial evidence on classic long-range airborne transmission
• Currently, there is no substantial evidence that SARS-CoV-2 can be transmitted efficiently over
long distances through airborne transmission like other pathogens such as TB, measles, or
varicella (chickenpox).
4
• Though aerosolized SARS-CoV-2 virus has been shown to be stable in aerosols for 3-16 hours in
laboratory settings,1,5 real-world factors such as temperature and relative humidity affect the
stability of the virus, while ventilation and exhaled viral load affect the concentration necessary
to infect others.
• Given the significant proportion of infections caused by persons with asymptomatic SARS-CoV-2
infection, it is estimated that global spread would have occurred much more rapidly if SARS-CoV2 spread primarily through airborne transmission.
6
Evidence of short-range airborne transmission in certain conditions
While uncommon, several instances of “short-range” airborne transmission beyond what could be
attributed to droplet transmission alone have been documented. These events are associated with
enclosed, indoor settings with poor or improper ventilation, prolonged exposure to infectious persons,
and activities that increase the rate of droplet and aerosol generation:
• An outbreak occurred in a restaurant in which directional airflow from an air conditioner is
suspected to have transmitted infected aerosols from the table of the index patient to adjacent
tables.
7
*
• An outbreak during a 2.5-hour choir practice with an attack rate of 53-87% occurred, with indoor
transmission likely augmented by singing.
8
• An outbreak involving two 50-minute rides inside a bus with recirculating air occurred, with
secondary individuals sitting closer to the index case being no more likely to get infected than
those sitting farther, indicating an extended range of transmission.9
*
• In an outbreak in 1 out of 7 wards of a nursing home during a period of low community incidence
occurred, the ward experiencing the outbreak had recently installed demand-controlled
ventilation that only circulated outside air based on indoor CO2 levels.
10*
• A cluster of cases were associated with a shopping mall, where possible virus aerosolization
occurring in confined spaces such as elevators and restrooms and contributed to indirect
transmission.
11
Updated 12/21/2020
• A cluster of cases associated with a squash court occurred, with individuals who played in the
same squash hall as the index case at least 45 minutes later were infected, possibly from
aerosols.
12
• An outbreak at a nightclub occurred in which infected staff likely caused multiple infections across
three different events.
13
• An outbreak of 112 cases occurred in 12 sports facilities over 24 days, where asymptomatic and
pre-symptomatic instructors taught fitness dance classes to 5–22 students in a room
approximately 60 m2 for 50 minutes of intense exercise.
14
Indoor Transmission through HVAC systems
We found no reported evidence of SARS-CoV-2 transmission occurring through heating, ventilation, and
air conditioning (HVAC) systems. SARS-CoV-2 RNA has been detected in multiple parts of HVAC systems,
though viable virus was not isolated. However, a potential limitation of available evidence is that the
sampling timeframe may not have captured the virus when it was infectious.
• Positive samples (swab and cell media) for SARS-CoV-2 RNA were found in the HVAC system of
COVID-19 wards and in the central HVAC system, which was located 5 floors above. Viral culture
was unable to detect viable virus in samples.
15*
• Tests for SARS-CoV-2 RNA were negative for swabs and air samples collected from the Diamond
Princess cruise ship in cabins with no COVID-19 cases, but that shared air circulation with COVID19 cabins via the HVAC system.16*
• Presence of SAR-CoV-2 RNA was detected in 25% of samples collected in 9 locations of the HVAC
system of a university hospital in Oregon. These samples were not evaluated for viral
infectiousness.
17
Ventilation Standards/Best Practices
Note: Some of the guidelines covered here can also be found in the Washington Department of Health
ventilation guidance and CDC ventilation guidance.
Given that SARS-CoV-2 is largely transmitted through close contact and larger respiratory droplets,
precautions are recommended and the addition of ventilation measures should be considered a
component in a layered approach. Ventilation measures should not be designed to completely substitute
other measures such as PPE, mask use, surface disinfection, and personal hygiene. Implementation of
some ventilation measures outlined here require technical expertise, and consultation with an HVAC
specialist or professional engineer is recommended.
Ventilation measures reduce the risk of SARS-CoV-2 transmission by diluting the concentration of
infectious aerosols in the environment. This is primarily achieved by filtration of indoor air or circulation
of cleaner air from the outside, either through 1) a central HVAC system, or 2) non-HVAC measures.
Ventilation measures affect the air exchange rate per hour (ACH), which is defined as the number of times
the air occupying the volume of a given space is exchanged with cleaner air.
HVAC Measures
• The CDC recommends installing filters in the HVAC system with the highest performance that
the system can handle. The American Society of Heating, Refrigerating and Air-Conditioning
Engineers (ASHRAE) recommends installing filters with at least Minimum Efficiency Reporting
Updated 12/21/2020
Value (MERV) of 13, provided there is no substantial impact on HVAC performance or occupant
comfort.
o MERV values range from 1 to 16, with higher values corresponding to better efficiency.
MERV 13 filters are at least 50% efficient at capturing particles in the 0.3 µm to 1.0 µm
size range and 85% efficient at capturing particles in the 1 µm to 3 µm size range (more
information on MERV standards can be found here.
o Higher MERV values can cause a drop in air pressure as more air is filtered, but provide
cleaner air with which to exchange the existing air in an enclosed space.
• Turn off demand-controlled ventilation, which automatically circulates outside air based on
temperature, humidity, or CO2 concentrations, to avoid build-up of indoor air
• Allow for HVAC systems to circulate outside air. Run HVAC systems on maximum to flush indoor
air 2 hours before and after occupancy.
o The CDC has guidelines for how long a system performing at certain ACH must be run in
order to remove the recommended 99% of airborne contaminants.
• Open outdoor air dampers to reduce or eliminate HVAC indoor air recirculation (this may be
difficult in hot or humid weather)
• Maintain relative humidity at 40-60% and temperature within 68-78F (ASHRAE guidance for
residential)
o Ecological studies have found higher transmission rates in geographical regions with
colder and dryer air; however, there is considerable potential for confounding in these
comparisons, and the role of temperature and humidity in SARS-CoV-2 infectiousness is
not clearly established.
18
o Surface stability of SARS-CoV-2 has been found to decrease with increasing temperature
and humidity.
19*
• Ensure that minimum rates for outdoor air circulation are met or exceeded.
o These minimum rates not only depend upon the room size, but also the number of
occupants, typical activities conducted within the room, and other environmental
factors. In general, doubling the occupancy will double the minimum required rate. For
more comprehensive standards and calculations for a wide variety of settings, see
Equation 6-1 and Table 6-1 of ASHRAE 62.1 (2019)
Non-HVAC Measures
These measures are best used to augment HVAC measures and are best implemented in settings with
limited or nonexistent HVAC systems.
• Place portable High Efficiency Particulate (HEPA) filter-equipped systems in critical areas.
o High Efficiency Particulate (HEPA) filters are at least 99.97% efficient in capturing
particles 0.3 μm in size and are even more efficient in capturing particles that are both
smaller and larger.
o As particles increase in size from 0.3 μm, they are more likely to be strained or blocked
since they cannot pass through the tightly woven fiber mesh of the filter. As particles
decrease in size from 0.3μm, their movement is increasingly dictated by random
diffusional collisions with other molecules rather than the airflow, and thus have
increasing probability to collide with the large combined surface area of every fiber in
the filter (see page 3 and page 7 of this NASA report for a more detailed explanation).
Updated 12/21/2020
o Portable HEPA-equipped systems have a Clean Air Delivery Rate (CADR) measured in
cubic feet per minute (cfm), which dictates how quickly they can remove particles in the
air of a room of a given size. Bigger rooms require systems with higher CADR.
Table: Portable Air Cleaner Size for Particle Removal (EPA)
Room area (ft2) 100 200 300 400 500 600
Minimum CADR (cfm) 65 130 195 260 325 390
For estimation purposes in a home setting. CADRs are calculated based on an 8 ft.
ceiling and an ACH of 4.875.
o A study (pre-print, not peer reviewed) found that HEPA filters installed in a poorlyventilated classroom setting with a combined ACH of 5.7 could reduce the inhaled viral
dose from a super-spreader in a room by a factor of 6.20*
• Open windows and doors to outside air. Use caution if outdoor air quality is poorer or not ideal
for occupant comfort (e.g. high pollution, colder outdoor weather).
• Use indoor fans to facilitate airflow following a clean-to-less-clean air pattern and blowing away
from people
o Place fans near windows or doors to blow out indoor air
o Reverse direction of ceiling fans to pull air up
• Reduce occupancy as much as possible to allow for physical distancing, and avoid occupant
activities that cause higher rates of emitting respiratory droplets and aerosols (e.g., singing,
shouting, cheering)
• Use faces coverings
o Face masks or other face coverings function as filters that are closest to the source of
infectious aerosols and can drastically reduce the concentration of viral particles in
indoor environments.
o Hospital rooms with unmasked COVID-19 patients, despite extensive ventilation
measures, were found to contain RNA-positive surface samples21 and air samples with
viable virus.2
*
o Air samples collected in indoor spaces (hotel room, car) where an individual who had
either confirmed influenza or suspected COVID-19 wore a cotton/surgical mask showed
a substantial decrease in aerosol concentration.
22*
o A modeling study exploring risk of transmission from super-spreaders in various indoor
settings (e.g. schools, offices) found that active ventilation combined with mask use
outperformed portable HEPA filtration with up to 9 ACH in all scenarios.
23
Ventilation Considerations for Special Settings: Schools
• HVAC and non-HVAC measures summarized here can be applied to a wide variety of contexts.
For example, in schools, the CDC ventilation guidance recommends increasing outdoor
ventilation by opening windows and using fans, improving central air filtration, and using
portable HEPA filtration systems in high-risk areas such as nurses offices.
• Maintain temperature and relative humidity at 72°F and 40-50% (ASHRAE winter classroom
guidelines).
Updated 12/21/2020
Other Measures
• Germicidal Ultraviolet Irradiation (GUVI)
o GUVI, which employs UV-C to inactivate fungal, bacterial, and viral pathogens, can be
installed in ducts or as ceiling fixtures to disinfect indoor air (see ASHRAE guidelines)
o GUVI can be costly (can be upwards of $1,500) and potentially harmful to occupants,
thus they are typically only used in high-risk settings such as TB wards.
o A modeling study estimates that installation of safer far-UVC in populated rooms could
increase SARS-CoV-2 disinfection rates by 50-85%.

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PostPosted: Mon Dec 28, 2020 9:22 pm    Post subject: Reply with quote

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2774463


December 23, 2020
Assessment of Air Contamination by SARS-CoV-2 in Hospital


Quote:
SettingsQuestion What is the level of air contamination from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in different hospital areas, and what factors are associated with contamination?

Findings In this systematic review of 24 studies, 17% of air sampled from close patient environments was positive for SARS-CoV-2 RNA, with viability of the virus found in 9% of cultures.

Meaning In this study, air both close to and distant from patients with coronavirus disease 2019 was frequently contaminated with SARS-CoV-2 RNA; however, few of these samples contained viable viruses.

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PostPosted: Thu Feb 04, 2021 9:50 pm    Post subject: Reply with quote

i have been adding H2O2 to my mouthwash for a long time.

https://www.youtube.com/watch?v=ldFRt-i3QzY


[b] Mouth wash,
Colchicine and Vitamin D
[/b]

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PostPosted: Sun Feb 07, 2021 10:49 pm    Post subject: Reply with quote

this one found there was no correlation to being safer wearing a mask. ya with caveats.

https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30985-3/fulltext?fbclid=IwAR1cuMiAbdbZyrUQ1CIfqhECI_GZy4QcG1gTFuW68bmcAydgONT3MBd4O3k


Transmission of COVID-19 in 282 clusters in Catalonia, Spain: a cohort study


Quote:
Introduction
According to current evidence, COVID-19 is primarily transmitted from person to person through respiratory droplets, as well as indirect contact through transfer of the virus from contaminated fomites to the mouth, nose, or eyes.1, 2 As with most respiratory viral infections, some transmission through smaller aerosols is likely to occur, but their relative contribution compared with droplets remains unclear. Several outbreak investigation reports have shown that COVID-19 transmission can be particularly effective in confined indoor spaces such as workplaces, including factories, churches, restaurants, shopping centres, and health-care settings.3, 4, 5, 6 In Spain and many other countries, health-care workers have had a high rate of COVID-19 infection.7

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