Coronavirus
Technology Solutions
Congressmen Urge Biden to Provide N95 Masks for
Everyone
Reinfection is Increasingly Documented
Face Masks and HVAC have to be Considered
as Part of a Total Solution
Vermont HVAC Contractors Did Well in 2020
Denver Schools
Adding Room Air Purifiers
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Congressmen Urge Biden to Provide N95 Masks for
Everyone
Vermont Sen. Bernie Sanders and a handful of his
Democratic colleagues are urging President Joe
Biden to explore options for making higher
quality masks available to the public through
the U.S. Postal Service to help stop the spread
of COVID-19.
Calls have been growing from public health experts for the federal government to provide
updated guidelines on the use of better quality
masks and rollout a national effort to get
high-filtration face coverings, like N95s, to
the public as the pandemic continues to rage.
In
a letter sent to Biden Sanders, Reps. Adam
Schiff and Ro Khanna, both of California, and
Sen. Brian Schatz of Hawaii asked that the new
administration prioritize educating Americans
about higher quality masks. They also encouraged
the president to examine options for using the
USPS to distribute medical masks and for making
them available for pick up at locations in local
communities.
“Wearing a cloth face mask is still the
official recommendation of the CDC, but there
has been little education or outreach about what
kind of masks are most effective,” the
politicians wrote. “While many Americans
understand that wearing a mask can help prevent
transmission of the disease, many don’t realize
that a high quality mask can make it far less
likely that the wearer will contract the
disease, even if exposed to an infectious
person. The White House has recognized this fact
by requiring staff to wear N95 masks on the
premises. Other nations, including Germany and
France, have provided their citizens higher
quality masks, or reimbursed them for the
purchase.”
The lawmakers also called on Biden to consider
invoking the Defense Production Act to increase
the available supply of higher quality masks.
“As more Americans are vaccinated each day,
there is a light at the end of the tunnel,” they
wrote to the president. “But with over 150,00
Americans still being infected each day,
thousands are dying, and there is rising concern
about variants of the virus that may be
significantly more infectious. We must do more
to reduce the spread of this virus. We have no
time to waste.”
Experts who have been pushing for such moves by
the federal government hailed the letter as a
big step forward for getting more people wearing
higher quality masks.
“The momentum is seriously shifting,” Dr.
Abraar Karan, a physician at Brigham and Women’s
Hospital, wrote of the letter.
Karan, with his Brigham and Women’s colleague
Dr. Ranu Dhillon, has been pushing for a
national high-filtration mask program in the
United States that would have medical masks,
like N95s, distributed to households across the
country.
Joseph Allen, an associate professor and the
director of the Healthy Buildings program at the
Harvard T.H. Chan School of Public Health, also
hailed the development. In an op-ed for The Washington Post last week, Allen presented the
case for why “everyone” should be wearing an N95
mask at this point in the COVID-19 pandemic.
Reinfection is Increasingly Documented
Evidence is mounting that having COVID-19 may
not protect against getting infected
again with some of
the new variants. People also can get second
infections with earlier versions of the
coronavirus if they mounted a weak defense the
first time, new research suggests.
How long immunity lasts from natural infection
is one of the big questions in the pandemic.
Scientists still think reinfections are fairly
rare and usually less serious than initial ones,
but recent developments around the world have
raised concerns.
In South Africa, a vaccine study found new
infections with a variant in 2 percent of people
who previously had an earlier version of the
virus.
In Brazil, several similar cases were documented
with a new variant there. Researchers are
exploring whether reinfections help explain a
recent surge in the city of Manaus, where
three-fourths of residents were thought to have
been previously infected.
In the United States, a study found that 10
percent of Marine recruits who had evidence of
prior infection and repeatedly tested negative
before starting basic training were later
infected again. That work was done before the
new variants began to spread, said one study
leader, Dr. Stuart Sealfon of the Icahn School
of Medicine at Mount Sinai in New York.
“Previous infection does not give you a free
pass,” he said. “A substantial risk of
reinfection remains.”
Reinfections pose a public health concern, not
just a personal one. Even in cases where
reinfection causes no symptoms or just mild
ones, people might still spread the virus.
That's why health officials are urging
vaccination as a longer-term solution and
encouraging people to wear masks, keeping
physical distant and wash their hands
frequently.
“It’s an incentive to do what we have been
saying all along: to vaccinate as many people as
we can and to do so as quickly as we can,” said
Dr. Anthony Fauci, the U.S. government’s top
infectious disease expert.
“My looking at the data suggests ... and I want
to underline suggests ... the protection induced
by a vaccine may even be a little better” than
natural infection, Fauci said.
Doctors in South Africa began to worry when they
saw a surge of cases late last year in areas
where blood tests suggested many people had
already had the virus.
Face Masks and HVAC have to be Considered as
Part of a Total Solution
The problem
with COVID-19 and ventilation is
counterintuitive. With most inactive airborne
contaminants like volatile organic compounds and
carbon dioxide, we achieve an acceptable level
of dilution to maintain an acceptable threshold
limit for these common contaminants through
prescribed quantity of outside air in the supply
air based on occupancy or over time.
Generally,
higher than code ventilation and overall airflow
rates flush out contaminants in the occupied
space more efficiently, though at greater energy
usage versus code ventilation rates. For
biological contaminants, specialized HVAC
systems and room arrangements, e.g., positive
and negative pressure isolation rooms, direct
airflow from clean to contaminated and exhausted
without recirculation in the space. The relative
location of the patient and health care workers
determine whether it’s an isolation or
protection room. Most HVAC engineers understand
this well.
The
challenges with COVID-19 are twofold. First,
aerosolized COVID-19 generally behaves like
other airborne contaminants and tends to diffuse
within a space and moves with air drafts. Unlike
inactive contaminants however, repeated doses of
exhalated virus being circulated throughout the
space on drafts can infect people far away from
the source. Although greater ventilation and
airflow will dilute the concentration, they also
increase recirculation of the virus in the
breathing zone through drafts.
Second,
unlike the negative or positive pressure
isolation room described above, large numbers of
unidentified, infected persons moving about
freely in an enclosed space poses an immensely
greater design challenge.
Before
COVID-19, the free movement of people with a
potentially deadly respiratory diseases were
relatively rare in public spaces. Sick people
were generally symptomatic before they were
highly contagious and easier to identify and
isolate through the public health system. Now,
we are seeing that a majority of people who are
COVID-19 infected and contagious are unknown,
even to themselves and asymptomatic carriers. As
such, the infection control isn’t occurring in
an engineered health care facility isolation
room.
Instead, we
now have public spaces like office buildings,
retail outlets, schools, restaurants and other
public buildings that were never designed to
control the person-to-person spread of
respiratory virus laden air in the same space.
Additionally,
the COVID-19 infected person is typically moving
about freely within the public space. That makes
the engineered removal of the airborne virus
contaminants virtually impossible. To make
matters even more complicated, the current
research indicates there is a significant risk
of spreading the disease through aerosolized
virus particles which remain suspended in the
occupied space.
Within all
enclosed spaces, the first line of defense
against the spread of the virus is wearing a
face mask according to public health agencies like the Centers for Disease Control
and Prevention and World Health Organization.
Whether layered cloth, surgical or
N95, masks specifically limit the spread of
exhaled respiratory virus particles in droplets
and even aerosol form. If a mask can
significantly limit the release of the virus
into the ambient conditioned air with negligible
viral load, then there is very little concern
the HVAC system will spread the airborne virus
particles past the masks to adjacent or nearby
people. Although this concept has been
communicated clearly by health experts, there
has been resistance due to external social
factors that are causing a significant portion
of the population from regularly wearing a mask
in public. This is unfortunately causing the
infection rate to explode across the country.
Thus, we are back to engineers trying to come up
with work arounds in public spaces.
Due to the
variability of space layout and relatively high
occupant density of conventional office spaces,
the risk of spreading the infection can be very
high. A problem with the majority of
conventional office HVAC design and construction
is that it assumes the only contaminants in
offices are benign gases and particulates that
can freely mix throughout the space and be
diluted safely through a thorough mixing of the
ambient air and fresh air in the breathing zone.
The more the ambient air is mixed and replaced,
the better the IAQ is assumed to be. Engineers
aspire to design and have installed HVAC systems
with no stagnant air pockets and a uniform
temperature distribution.
To achieve
that, engineers depend on traditional overhead
office HVAC to take advantage of the coanda
effect to have supply air hug the ceiling and
gradually diffuse and drop as the airflow
velocity drops to where the effect no longer
exceeds the gravity effect on the colder, denser
air and it drops to the occupied zone and
offsets the heat sources of the space.
In perimeter
zones, the distribution gets trickier due to the
need to push air down along the perimeter
fenestration and “curl” back up along the
interior. That circular pattern is the start of
problems in the post COVID-19 world. To identify
the problem, let’s discuss how we currently know
the virus to spread in enclosed spaces. The
virus spreads from infected people through
respiratory droplets and aerosol and the virus
from these vectors can linger in the air for
hours while larger droplets that precipitate can
survive on some types of surfaces for days.
Unlike in an engineered space like a health care
isolation room, it can be spread by multiple
people at the same time in an enclosed space
with no specific dispersal pattern from the
exhaled breath of mobile and static people.
https://www.csemag.com/articles/making-iaq-better-with-covid-19-in-the-air/
UK Schools Need New Ventilation Guidelines for
Schools
Schools urgently
need guidelines on how to improve ventilation in
classrooms to reduce the risk of coronavirus transmission,
scientists have said.
Improving air
quality in
classrooms should be as important as social
distancing, wearing masks and washing hands,
according to a new paper, written by doctors
from Imperial College London and a secondary
school headteacher in Middlesex.
The authors said schools could look towards the
airline industry, saying the risk of catching
coronavirus on a flight was currently lower than
in a classroom.
Dr Kaveh Asanati, the lead author, said a
“multi-layer risk reduction strategy” appears to
be “working efficiently” in this industry.
While few school buildings have HEPA filtration,
school could look at using portable HEPA
filtration units, the new paper
in the Journal
of the Royal Society of Medicine suggested
To keep schools open, there is an urgent need to
implement more effective on-site mitigation
strategies, with particular attention to
ventilation and testing,” Dr Asanati from the
National Heart & Lung Institute, Imperial
College London, said.
Vermont HVAC Contractors Did Well in 2020
Vermont HVAC installers say 2020 was one of
their biggest years ever — with homes and
businesses across the state scrambling to
upgrade heating, ventilation and air
conditioning systems to meet the unique demands
of the pandemic. “I
don’t remember a time we’ve ever been that busy
before,” said Max Balderas, office manager at
Red Rock Mechanical in Burlington. “Our
installation guys were booked three or four
months out at one point.”
Even service technicians were booked three or
four weeks out over the summer, which he said is
practically unheard of in this line of work.
Commercial building owners sought to upgrade
ventilation systems to improve indoor air
quality and reduce the spread of Covid. The
boom didn’t start immediately after Covid-19 hit
in March. Initially, contractors said work
slowed way down — much as it did for everyone
else. “At
the beginning of Covid, all our calls stopped,”
said Jay Ferguson, operations manager at Jay
Mechanical Inc. in Burlington. “People were more
afraid of the virus I think, than dealing with
no heat or a leak in a faucet or something.” All
of that changed in the span of a few weeks when
warm weather arrived. People who weren’t used to
being trapped inside at home in the summer
wanted air conditioning.
Mark Stephenson, a manager at Vermont Energy in
Williston, said companies had to adapt to how
people were using space during the pandemic.
“Offices closed, homes became offices, retail
spaces did everything they could to bring people
back, as did schools and other meeting places,
everything was different,” he said.
Many commercial spaces in Vermont already have
rooftop HVAC units that bring in air from
outside, which he said is what is needed for
appropriate airflow indoors to reduce the risk
of coronavirus transmission. Most new buildings
have energy efficient HVAC systems installed,
which are also great for air flow. But many
older buildings don’t have adequate
ventilation.
“We did a project recently at a housing facility in
Burlington where their common areas where they
cook and have meetings, didn’t have that type of
equipment,” Stephenson said. “They had a 10 or
15 year old building, and they wanted to ensure
the health of their residents, who are older, so
they spent the money and got a high-efficiency
ventilation system.”
He said he’s seen a lot of businesses make those
kinds of investments this past year. Vermont
companies had been slowly adapting to higher air
quality standards, he said but once the pandemic
hit, clean air became a top priority in a way
he’d never seen before.
“Air is not something you can see, and if you can’t
see the problem, it’s hard to muster up
enthusiasm about,” he said. “But now, people
really feel the problem.”
For the past few months though, business has begun
returning to normal.
“Gradually as summer ended and winter started to
come around, we started to slow down,” Balderas
said. “We’re obviously still doing boilers and
furnaces, but we’re not even close to how busy
we were over summer.”
Denver Schools Adding Room Air Purifiers
As school districts begin their
second semester trying once again to bring
students into classrooms, more are adding new
layers of protection — this time looking to
address airborne transmission of the coronavirus.
They’re adding filters to catch
smaller particles and retrofitting heating and
air conditioning systems. And some are trying
newer methods to treat indoor air — although
experts caution against unproven technologies.
The Denver school district, the
largest in Colorado, is working with university
researchers to place and track the effectiveness
of air purifiers in classrooms across 17
schools.
The Adams 14 district, a smaller
district serving students from more low-income
families, has spent $1.1 million on new devices
for every classroom. The money came from a grant
to help schools reopen buildings. The device
pulls oxygen and moisture out of the air and
pushes out dry hydrogen peroxide that can kill
viruses in the air.
In Mapleton, classrooms and buildings
have had portable air purifiers since August.
Officials are evaluating which rooftop units
might need replacing if more money becomes
available.
Officials in other school districts
including Jeffco and Aurora have said they are
reconfiguring heating, ventilation, and air
conditioning systems to pull in more outside air
to dilute particles indoors. A spokesperson for
Jeffco also said the district has one school
piloting ultraviolet lights but did not provide
more information. Some districts have also
replaced HVAC filters with higher-rated ones
that may trap smaller particles. Others, like
Westminster, haven’t made any upgrades.
Several researchers said that
improving ventilation and air quality are
important factors in making school buildings
safer, and that administrators are better off
sticking with tried and true methods like
bringing in more outside air and using
higher-quality air filters.
“The way to get the virus out of our
indoor air and to make it safer, is to dilute
the air and clean the air,” said Shelly Miller,
professor of mechanical engineering at the
University of Colorado Boulder. “For schools,
the easiest thing to do is to buy HEPA air
cleaners.”
That’s the idea behind a pilot
project in Denver schools. Mark Hernandez, a
professor of civil engineering at the University
of Colorado Boulder, has spent decades studying
how to create public spaces with clean and safe
air to breathe.
Because of his previous work, months
ago philanthropists contacted him to see how to
apply his research to help schools reopen
safely. With their donations, Hernandez
purchased portable air filters and reached out
to Denver schools.
“This was: get it to you there, now,”
Hernandez said, “with a high probability of
success. It’s about protecting public health now
— with the tools we have now.”
Around November, when most school
buildings were closing for the second time as
cases of COVID spiked, Hernandez and about a
dozen students and graduates went into schools
that DPS identified as having the oldest air
quality systems.
Then, when buildings were empty, the
team filled schools with carbon dioxide and
placed sensors in all classrooms to track how
fast the existing systems were able to clear the
air.
The team identified the classrooms
with the least effective air systems. They also
mapped out the optimal locations to place air
filters and placed about 120 filter units in 17
city schools.
The district estimates it would take
about $2.5 million to provide all of its
classrooms with such filters.
But Hernandez believes that many
classrooms wouldn’t need any filters. Some rooms
he encountered, he said, “had air exchange as
good as CDC recommends for medical exam rooms.”
The classrooms that Hernandez
targeted also got new sensors to monitor
particles. He created a dashboard that tracks
that data live. That will enable district
officials to monitor and make adjustments when
they see that a unit is not effectively
filtering. In such a case, they could increase
the motor speed of the unit, change the filters,
or move the unit to a more central location in
the room.
“High efficiency filtration has been
around,” Hernandez said. “It just hasn’t been
used in high-density classrooms as much as it
could be.”
Mapleton district officials looked
into air purifiers in their classrooms following
guidance from a Harvard report this summer that
described it as one layer of protection in
addition to mask wearing and social distancing.
“We looked at what is it going to
take to get us back,” said Mapleton
Superintendent Charlotte Ciancio. “We used all
of the research. And when we researched air
quality, really, they talked about air filtering
systems.”
Several school buildings in Mapleton
are newer and have HVAC systems that were able
to be upgraded with the highest-rated filters,
but a few of the older buildings, like where
Ciancio’s office is, just got extra portable air
purifiers.
Ciancio points to the low rates of
COVID in Mapleton schools even as rates in the
surrounding community soared as her assurance
that everything is working.
Last fall, the approximately
9,000-student district had just two outbreaks,
as defined by the state, at schools. The
district’s dashboard last week identified 200
total positive cases among students and staff
since the start of the school year.
In many school districts, the desire
to create safer indoor spaces runs into the
reality of older buildings that have been
remodeled in less-than-ideal ways over the
years.
Adams 14 buildings, for instance, can
only accommodate HVAC filters up to a rating of
10, which is less effective than the 13 rating
that experts suggest. Even the district’s newest
building, Adams City High School, built in 2009,
lacks an HVAC system that can accommodate a
higher-rated filter, district officials said.
“Older buildings are much harder to
deal with,” said Jim Malley, a professor of
civil and environmental engineering at the
University of New Hampshire. “Irregular-shaped
classrooms are harder to deal with.
“When you have no way of getting
outside airflow, that’s a real problem. I think
it’s reasonable to think COVID transmission
would be higher in those rooms. When possible,
those need to be not used, but in some places
that won’t be feasible.”
The Adams 14 school district
initially focused on increasing the outside air
coming into schools. But according to the
district’s application for the grant that paid
for the new hydrogen peroxide systems,
filtering, heating, cooling or otherwise
controlling that outdoor air resulted in
“unsustainable” utility cost increases.
One company that was already working
with the district on career opportunities for
high school students recommended the Synexis
hydrogen peroxide systems, which it sells. Adams
14 is one of the first school districts to roll
out the devices districtwide. The Upper Rio
Grande School District and a private school in
Vail have already installed systems.
Experts say that the technology
doesn’t have a long track record, despite the
research that the company touts, and some
experts worry that doing chemistry in the air
could result in unintended consequences.
The company touts clients like
professional sports teams, the Kansas State
University, and St. Judes Hospital, though not
the one in Colorado. Company officials say they
have lots of research that shows their
technology is safe.
CEO Eric Schlote said Synexis is
presenting research to the FDA to get approval
to make more extensive claims about its ability
to rid the air of microbes.
Adams 14 officials said they have no
concerns.
“We think we’re taking the right
safety precautions,” said Ron Cabrera, Adams
14’s chief of staff.
Several researchers do not think it’s
a good idea.
“I do not recommend hydrogen
peroxide, spraying any cleaning chemicals into
your air or any incense, all of this stuff,
especially when the space is occupied,” Miller
said. “I know some schools are doing it, but
indoor air quality scientists do not recommend
it.”
Delphine Farmer, an associate
professor of chemistry at Colorado State
University, said schools should be cautious
about any technology that purports to use a
chemical reaction to kill the virus in the air,
since any chemical reaction will produce
byproducts.
“I would be concerned and I would
want to know: If you are using enough hydrogen
peroxide to kill viruses, would you also be
using enough to change the chemistry inside the
building?” she said. “I have grave concerns that
I haven’t seen any scientific literature on the
efficacy or the other byproducts, which, as a
chemist, would want to see studied before it was
implemented.”
In particular, Farmer is concerned
about the use of bleach fumigation,
ion-generating systems, and ozone-generating
systems. Some of these are in use in hospital
settings, but she said that doesn’t make them
appropriate for schools.
Synexis systems don’t generate ozone,
Schlote said. Adams 14 did not respond to
questions about the cost of maintaining the 427
devices. That ongoing maintenance includes
changing a filter, the UV light, and a
cartridge-like piece, every 90 days, on each
device.
Daniel Stone, said that when he first
learned about the district’s investment he was
excited. But after looking into the devices and
the research more, he was concerned.
“One of their own pages says
something that it’s like magic,” Stone said. “I
like magic, but not when it comes to my health.”
Stone has been able to continue
teaching remotely, and said he wants to be
hopeful, and for now he said he’s glad that
students and some teachers had the choice to
stay home.
“Hopefully, it’s harmless,” he said.
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