Coronavirus
Technology Solutions
People With Severe Allergies Will Not Receive
the Vaccine
New Coronavirus
Cases in Seattle Jail with MERV 10
Filters
ASTM Base Efficiency
Requirement can be Combined With More Efficient
Masks to Greatly Reduce COVID Transmission
ASTM Working with CDC on a Minimum 20%
Efficiency Mask
Are Nanofiber Media Masks More Comfortable?
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People With Severe Allergies Will Not Receive
the Vaccine People with a history of significant allergic reactions should not have the Pfizer/BioNTech Covid jab, regulators say. It came after two NHS workers had allergic reactions on Tuesday. The advice applies to those who have had reactions to medicines, food or vaccines, the Medicines and Healthcare products Regulatory Agency said.
In terms of needs for HVAC and masks this new
development needs to be taken into account.
·
Worldwide, adverse drug reactions may affect up
to 10% of the world’s population.
·
Worldwide, the rise in prevalence of allergic
diseases has continued in the industrialized
world for more than 50 years.
·
Worldwide, sensitization rates to one or more
common allergens among school children are
currently approaching 40%-50%.
It is possible that other vaccines will be
recommended for these individuals. Another
variable is the length of vaccine protection. Is
it months or years? A third variable is
infection transmission from vaccinated patients.
All of these impact the long term filtration
needs.
New Coronavirus
Cases in Seattle Jail with MERV 10 Filters King County Jail’s downtown
Seattle location has confirmed 16 new cases of
COVID-19, according to a press release sent to
reporters on the afternoon of Dec. 7. “This is the first time we
have confirmed cases of COVID-19 from
coronavirus exposures that occurred within our
jails,” the press release said. “Public Health
contact tracers are working to identify any
inmates, staff or visitors who may have had
close contact with the recently identified cases
among our in-custody population. Before testing
positive, this inmate had been in a wing that
houses inmate-workers – those who help in jail
operations.”
In an email to the Emerald on
Dec. 8, King County Jail Public Information
Officer Noah Haglund said that those who tested
positive were between the ages of 20 and 54.
This falls in line with the state Department of
Health’s demographics
chart that
shows this age range currently has the highest
case rate throughout the state.
The press release also said that staff have
decontaminated the wing of the jail where the
sick people had been jailed, as well as
hallways, elevators, and transport vehicles they
may have used.
Haglund said in his Dec. 8 email that “cleaning
and disinfection occurs daily in all areas of
the jail facilities. Paper towels and
disinfectant are available in general population
for inmates to do additional cleaning as
necessary.” However, he did not address the Emerald‘s
question regarding exactly what cleaning
procedures were in place before the outbreak,
and if they have changed since.
He also said that those jailed at the Seattle
King County Jail “receive, at minimum, a clean
cloth mask daily. These masks have two layers.
Cloths masks are washed and dried in the jail’s
laundry program following industry standards.” In response to the Emerald‘s question about what kinds of masks those in quarantine receive, Haglund said that “inmates identified as droplet precaution and COVID+ receive surgical (procedure masks) prior to their transfer to droplet precaution and COVID+ housing. Inmates in quarantine – those who test negative for COVID, but who have been in close contact with someone who tested positive – currently receive cloth masks.”
He did not address the contention by
protestors who were jailed over the summer that
they were denied clean masks.
The press release said that there had been 47
total cases of COVID-19 amongst its jail staff
and inmates, before this past weekend’s
outbreak. It also claims that the King County
jail system has been taking “aggressive”
measures to prevent and limit infection.
This past summer, the King County Jail was in
the process of upgrading its MERV 10 filters to
MERV 13 filters with the aim of finishing by
August, Haglund told the Emerald in
a July 21 email. The United States’
Environmental Protection Agency webpage on
the topic of indoor air filters that can help
protect people from COVID-19 says that MERV 13
filters — the highest-rated kinds of filters —
can “trap smaller particles, including viruses.”
In the July 21 email, Haglund also said that the
jail’s 13 medical cells were “designed with
positive-airflow capability,” which means that
air can leave the room without circulating back
in, filtering out any airborne particles that
originate in the rooms.
When asked how those who tested positive were
being housed, given that there were only 13 such
cells available, Haglund said that there is a
32-bed unit at the MRJC “dedicated for housing
COVID+ inmates.”
“Medical isolation for COVID+ patients does not
require directional airflow. Patients who test
positive for COVID-19 are housed in individual
cells and are kept separate from direct
interactions with other patients,” Haglund said.
Haglund said that the 54 people who tested
negative were not given their own cells at the
King County Jail in downtown Seattle.
“The inmates will remain in dorms and continue
to maintain social distancing, wear masks, clean
and disinfect daily and as appropriate, and
quarantine in place for up to 14 days,” he said.
It is unclear how people jailed at the King
County Jail could maintain social distance, if
they are sharing cells, but the Emerald has
followed up with this question. It has also
asked again what cleaning procedures are in
place, both at the King County Jail and at the
MRJC.
ASTM Base Efficiency Requirement can be Combined
With More Efficient Masks to Greatly Reduce
COVID Transmission
There are presently many masks being worn where
even with a perfect fit the efficiency will be
well less than 20%.
So an ASTM standard which would result in
all masks being somewhat effective will be a
contribution. With CATER Mask Decisions
we hope to guide a majority of purchasers to
purchase much more efficient masks.
Mask Efficiency by Percentage of Wearers
At the very least we should be able to achieve a
distribution where 20% are wearing masks which
are 80% efficient or greater and 10% are wearing
very efficient masks. The masks are part of the
swiss cheese defense program. The fewer holes in
the mask layer, the less need there is to
eliminate holes in the ventilation layer or in
quarantine.
The ASTM working group struggled to find
compromise on inward leakage testing. There is
no consideration of quality control. So the
reality in terms of virus protection ranges
roughly from 5 to 80%
Mask Effectiveness by Percentage of Wearers
It is therefore important that the ASTM standard
be supplemented by evaluation systems which
provide net effectiveness even if it is a range
such as shown in the following chart.
This effectiveness rating could be
net efficiency as calculated in the
following example.
ASTM Working with CDC on a Minimum 20%
Efficiency Mask
Obtaining agreement of mask standards is
difficult considering the revenues for
inefficient masks are many billions of dollars
per year. So the fact that ASTM has been working
with CDC and can probably have a consensus on a
minimum 20% efficiency mask is significant.
Also the clarification of methods to test
efficiency is also an important part of the
effort
This week the group received a
request to vote on
Ballot
Action: Working Draft #7, Standard Specification
for Barrier Face Coverings
Here are some
of the notes and clauses relative to
leakage assessment.
Note 4
– The leakage assessment represents the total
inward leakage likely to occur during wear.
Whether measured quantitatively or
assessed qualitatively, the leakage assessment
does not represent the likely outward leakage of
particles generated by the wearer. Thus, no
claims may be made with respect to the degree of
source control offering by the barrier face
covering based on the leakage assessment.
Note 5
– Leakage assessment, if measured quantitatively
on a barrier face covering that rests closely on
the face and thus has minimal inward volume, may
not be representative of true inward leakage.
4.1.3 Sub-micron particulate filtration
efficiency and air flow resistance do not
account for the leakage of air around the
perimeter of the barrier face covering. A
leakage assessment using a design analysis of
the product is required to assess the ability of
the barrier face covering design to minimize
inward leakage and provide appropriate coverage
for a range of wearer faces of different
dimensions. The design analysis can be conducted
by the manufacturer in a number of different
ways. The standard also permits supplemental the
use of quantitative information obtained from a
modified form of Test Method F3407 using test
subjects. This test yields a reportable ratio of
outside particulate concentration to the
concentration of particles in the wearer’s
breathing zone. Thus, a leakage ratio of 1.0
indicates the outside and inside environments
are equal and that particulate flow through gaps
in the barrier face covering (in addition to any
particulate that pass through the filtration
materials of the product
5.4 Leakage Assessment
5.4.1 The
leakage assessment shall be reported by
the manufacturer through a product design
analysis self-declaration.
5.4.2 The required self-declaration shall report
that the product minimizes leakage around the
edges or other areas of the product based upon
an analysis of the product design.
This statement can be included on any
self-declaration required as part of Guide
F3050, under Section 12 of this specification.
5.4.2.1 The manufacturer is permitted to conduct
quantitative testing
to supplement its product design analysis
self-declaration. When used, the leakage ratio
shall be evaluated using Test Method F3407, with
the modifications specified in 8.3.
5.4.3 Where barrier face coverings are reusable
and intended for laundering or cleaning, the
product design analysis shall be applied to
barrier face coverings both in a new condition
and after the maximum of laundering or cleaning
cycles as specified by the manufacturer
according to the manufacturer care instructions.
Note
13 – Examples of means to accomplish a leakage
assessment could include dimensional analysis,
computer modeling, placement of barrier face
coverings on standardized head or head-torso
forms and judging their respective areas of
coverage and conformity to the head or
head-torso form face showing conformance to the
fit and sizing characterizations of AATCC
M14-2020, or performing a quantitative analysis.[1]
A minimum particulate efficiency is cited
Subsequently in the draft is an example showing
a better level 2 performance.
TABLE 2 Separate Classification of Face Covering
Performance PropertiesA
This ASTM standard is a sign of progress.
It alerts buyers that all masks are not
equal. Suppliers of 95% efficient masks with
less than 8% inward leakage can use this
standard as a base and provide evidence as to
why their product achieves their claims,
Are Nanofiber Media Masks More Comfortable?
Nanofibers are incredibly small, synthetic
fibers – each measuring one thousand times
thinner than a human hair. Nanofibers form
complex strength through spiderweb-like
structures, which have an advantage over
conventional or even natural fibers due to their
extraordinarily large surface area and tiny pore
size. This combination creates maximum air flow
and particle capture – significantly more than
other synthetic or natural filters, achieving
greater efficiency down to PM0.3 microns.
This image helps us visualize the size of a
nanofiber when compared to both hair and a speck
of pollen:
Its small size provides an array of benefits
when utilized in face mask technology –
including advanced protection and better
comfort.
Featuring a weaving design closely packed
together so microscopically that we are unable
to see them with the human eye, nanofibers craft
a small pore size and high surface-to-volume
ratio. This means the surface area and pores of
a face mask with nanofiber technology will not
allow cells to pass through to reach the wearer.
Simply, due to the unique and tough threading of
the nanofibers, everyday dangers such as
pollution, viruses, bacteria and more will be
unable to cross the threshold of the mask,
thereby enhancing protection from the outside
world. Not even water or liquid can penetrate
the surface, which is why it is such an
essential component of any truly effective face
mask.
Additionally, this works two ways, as a mask is
not only a protector of the individual wearing
the mask, but it also serves to halt the spread
of germs as well. When you’re sick, you should
have a mask on – especially if there are other
people in your household or if you are traveling
out to an appointment with a doctor. Nanofibers
block larger cells from escaping the mask, which
helps to ensure less spread of any unpleasant or
harmful ailment to unsuspecting passersby or
loved ones.
While many are aware of the advanced protection
that nanofibers provide in face mask technology,
what may come as a surprise is that this
material is also significantly more comfortable
than other fibers. The complexity of the
microscopic hair-like design makes the mask
lightweight and, therefore, extremely
breathable. It’s not simply a cloth over your
face – it’s a material that works with your body
to trap cells out but allow air to flow in, so
you don’t feel cramped or suffocated. This also
allows for better temperature regulation. More
airflow means less of a “humid” feeling, as if
the mask were a part of your face rather than
your face feeling as if it’s sweating into the
mask. The light, soft and airy material of
nanofibers ensures both short-term and long-term
wear is much more comfortable.
Overall, nanofibers have revolutionized the way
we keep people safe – with transformational
applications in healthcare advancements such as
tissue engineering, wound dressings, face masks
and more.
International Filtration News Insights
International Filtration News
has lots of good information relative to masks
We work closely with Matt Migliore who is the
editor. He just wrote an article on nanofibers
which is quite relevant. Here are some excerpts.
According to Dr. Vijayakumar, to truly deliver
on the benefits of increased efficiency and
decreased resistance in the filter, nanofibers
need to be in the ~100nm size range.
NXTNANO’s HYPR spinning production process is
capable of scaling to produce approximately 150
million square meters of Level 1 mask material
per year, according to McDowell. Described as a
derivative of electrospinning, the HYPR spinning
process allows NXTNANO to produce more and finer
fiber, more consistently, and with better
bonding than other nanofiber material options on
the market. It also permits flexibility to spin
multiple polymers simultaneously. “All of the
general issues you would see with
electrospinning we think we’ve pretty well
solved; for throughput, controllability, and
uptime,” said McDowell.
You can find the full article at
https://www.filtnews.com/nanofiber-filtration-challenges-and-opportunities/
There is an important article by Adrian Wilson
titled Facemask
materials, surface treatments, intelligent
sensors & carbon nanotubes.
Here is an excerpt.
NWI executive director Benham Pourdeyhimi
explained that the new media development arose
from reactivated work on microfibrillation,
which was initially undertaken for the
filtration industry.
N95 efficiency can be achieved with just two
layers of the new spunbond fabric. A combination
of one spunbond layer and a meltblown layer can
further achieve N99 efficiency.
The media also requires no electrostatic
charging, which has been another bottleneck in
the production of facemasks this year, and,
because the materials are strong – unlike
traditional meltblown materials – they can also
be cut and sewn by traditional techniques.
Further, they have the potential to be reused a
number of times after cleaning. The full article is found at https://www.filtnews.com/filtration-innovations-in-2020/
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