Correct and Effective Mask Use

The Optimistic Scientist explains...Corrective and Effective Mask Use

A mask may not protect the wearer, but it will help prevent the wearer from spreading the virus to other people.

Masks prevent respiratory droplets (produced by talking, coughing, and sneezing, for example) from spreading germs to other people. Some people find typical masks uncomfortable because they can trap moisture against the face and may opt for ones with one-way valves or vents. Unfortunately, this creates an effective channel for exhaled droplets to reach others, defeating the purpose of the masks. This is why the CDC recommends using masks without an exhalation valve or vent.

Masks alone are not enough.

You can reduce the spread of SARS-CoV-2 by wearing masks in addition to practicing other preventive measures, such as social distancing, frequent and effective handwashing, and cleaning and disinfecting frequently touched surfaces.

Surgical masks are ONE-WAY.

Let me repeat that one more time for emphasis. Surgical masks are ONE-WAY. The concept of flipping the mask based on situation is a MYTH. If you wear the mask inside out, it’s not going to help anyone.

The Optimistic Scientist shows how to properly wear a surgical/procedure/face mask. The blue side should face outwards.
If the mask has a blue or green side, this is the side that should face other people.
If the mask is all white, put the softest side to your face.
The Optimistic Scientist shows how to properly wear a surgical/procedure/face mask. The blue side should face outwards and the bendy part should be on the top and pinched around the bridge of the nose.
Surgical masks don’t work unless they completely cover your nose and mouth.
Pinch around the bridge of your nose.

Why are they one-way? Surgical masks can’t be reversed because they have three specialized layers. In the name of science, I dissected one so I could show you.

Zoomed in view of a surgical mask illustrating the stitching that links three distinct layers.

Zoomed in view of the stitching that keeps the 3 layers of a surgical mask together.

Zoomed in side view of a dissected surgical mask, illustrating the three distinct layers.

Dissected surgical mask, side view.

These handy little forms of PPE (personal protective equipment) are specifically designed to protect a patient on the operating table from the respiratory droplets of a surgeon, who is breathing, talking, and potentially sneezing above a patient’s open abdomen/brain/etc. They do this by intercepting and diffusing those droplets and by minimizing lateral dispersion (sideways spread). First, droplets are captured by a water-loving absorbent layer, typically white. Anything that makes it beyond this layer is then filtered out (remember, these filters won’t trap viruses because they are really tiny). If a droplet isn’t caught by the filter, it hits the final, water-repellant exterior layer, often blue or green, which further helps to minimize the chance it will spread to those around the wearer. These masks are not intended to protect the wearer.

Mask Layers

Outside – water repellent

Middle – Filter

Inside – water absorbent

Zoomed in view of the different materials used in the three distinct layers of a surgical mask labelled with the orientation.
Zoomed in view of the inside layer of a surgical mask. This is the moisture absorbent side and should be worn closest to your face.
Zoomed in view of the middle layer, or filter, of a surgical mask. Regardless of orientation, this remains in the middle. If the mask is worn incorrectly, the efficiency of this filter can be severely compromised.

Zoomed in view of the outside layer of a surgical mask. This is the moisture repellant layer and should be worn facing the wearer's environment. If worn incorrectly, this layer touches the face and allows the mask to get wet. This becomes uncomfortable but also severely reduces the efficiency of the mask at filtering droplets and protecting others. It's also uncomfortable for the wearer.

What happens if my mask is inside out?

If your mask is inside out, the moisture repellant side is up against your face. When you exhale, water vapor won’t be absorbed by the mask and it will become wet. The mask then loses its ability to efficiently filter and trap droplets and you will likely find the damp mask pretty uncomfortable. With the mask inside out, the absorbent layer now faces the environment and has become a droplet landing zone. If you touch the contaminated exterior of the mask and then touch your face, or re-use the mask instead of replacing it, you increase your chances of getting sick. This virus is already super effective at spreading; let’s not make it even easier!

Masks don’t work when:

  • dirty or wet
  • upside down/inside out
  • torn
  • not covering your nose or your mouth completely

Under any of the above conditions, the filtration efficiency and protective capability of the mask is compromised.

Mask illustrating an easy way to remember which side should face out. Brr it's cold outside. B for brr and blue, means the blue side is on the outside.
I’m a sucker for fun ways to remember things, so here you go!
B is for blue and brrrr.

Didn’t the CDC say NOT to wear masks?

Yes, but here’s why. Previously, the CDC and the WHO recommended that only those with symptoms should wear masks. They’ve since modified this recommendation because:

  • SARS-CoV-2 can be spread by asymptomatic individuals or before symptoms appear
  • Surgical masks are prioritized for healthcare workers coming into contact with many patients

You should still prioritize surgical masks for healthcare workers. Cloth masks, however, are more effective than not wearing anything — although not a substitute for social distancing, not touching your face (cloth masks also provide a tactile reminder not to touch your face), and frequent hand washing.

Let’s Review!

  • Wear a mask that properly fits, and in the right orientation.
  • Don’t wear masks with exhalation valves/vents.
  • Always practice social distancing and hand hygiene. Wearing a mask is not a substitute for these behaviors.
  • Don’t touch your face!

A final note

I don’t need to tell you that this pandemic has been difficult for so many people. Everything about our daily lives and how we provide for ourselves and our families has been affected. The disproportionate effect of COVID-19 on certain racial and ethnic minority groups has led to increased awareness of systemic racism and inequity, from housing to education and everything in between. If you don’t consider this virus a serious problem, I urge you to thoughtfully reflect on what privileges you may knowingly or unknowingly hold, and how no individual experience is reflective of our country as a whole. If you’re in a position to doubt whether or not this is a big deal, you may not recognize how fortunate you are to have some degree of financial stability or greater access to health care that others do not. I urge you to trust evidence-based science and to trust your public health officials. Please protect yourselves and others by observing the rules of masks, distance and hygiene.

Do you have questions, comments, or suggestions for my next experiment/dissection?

Email or comment below!


Surface Survival of SARS-CoV-2

Seriously, how long can this thing survive on surfaces?

In an earlier post, I referenced some preliminary research suggesting that SARS-CoV-2, the virus that causes COVID-19, can live in the air and on surfaces between several hours and several days. This work, originally released as a pre-print and recently finalized and published in the New England Journal of Medicine, found the virus is viable for up to 4 hours on copper, 24 hours on cardboard, 48 hours on stainless steel, 72 hours on plastics, and is also detectable in the air for 3 hours. 

A lot of posts present this information out of context and headlines can make it sound frightening, “SARS-CoV-2 Lives on Plastic for 72 Hours!!!” However, what’s more important is the amount of virus that’s still alive. It’s <0.1% of what the investigators started with. So, infection is theoretically possible but extremely unlikely at the levels they saw after a few days. 

Another important thing to mention lies in the experimental design of the aerosol component of the study. It has some caveats. They found that the virus can be detected in the air for 3 hours in the lab. However, in nature, respiratory droplets fall to the ground at a faster speed than the aerosols generated in their experiments. This is because the lab-generated aerosols are smaller (<5 μm) than what is produced from a cough or sneeze, so they remain in the air at face-height longer than the natural, heavier particles. It’s not a perfect comparison (though science rarely is, we just do our best). The size of these particles can affect how they move through the air and how they impact a surface. 

So, at the end of the day you’re more likely to become infected through the air if you’re next to an infected person versus a contaminated surface. Make sure you clean surfaces with disinfectant or soap – they work because they disturb the oily external layer of the virus keeping it from infecting your cells. 

Washington State Stay Home, Stay Safe 2 Week Order

Please be sure to refer to the original documents for questions or concerns relating to a specific situation.

“The less time we spend in public, the more lives we will save.”

Governor Jay Inslee


  • How Long? 3/25/20 – 4/5/20
    • Unless extended
  • You can still safely go outside as long as you remain at least six feet from each other.
  • Essential businesses can remain open if they follow specific sanitation and social distancing policies outlined by the CDC and WA public health.
  • Gatherings are banned
    • regardless of the number of people, public and private

What Does This Mean For Individuals?

You can only leave your home to do one of two things:

  • Essential activities 
    • Obtaining necessary supplies and services 
      • for family or household members and pets
      • such as groceries, food and supplies for household consumption and use
      • supplies and equipment needed to work from home
      • products necessary to maintain safety, sanitation and essential maintenance of the home or residence
    • Engaging in activities essential for the health and safety
      • of family, household members and pets
      • seeking medical or behavioral health or emergency services
      • obtaining medical supplies or medication
    • Caring for someone else
      • a family member, friend, or pet in another household or residence
      • to transport a family member, friend or their pet for essential health and safety activities
      • to obtain necessary supplies and services
    • Engaging in outdoor exercise activities
      • walking, hiking, running or biking
      • ONLY IF appropriate SOCIAL DISTANCING practices are used
  • Employment in essential business services 
    • Healthcare / Public Health sector
    • Emergency Services sector (Law Enforcement, Public Safety and First Responders, Public Works)
    • Food & Agriculture
    • Energy (Electricity, Petroleum, Natural and Propane Gas)
    • Water & Wastewater
    • Transportation & Logistics
    • Communications & Information Technology
    • Critical Manufacturing
    • Hazardous Materials
    • Financial Services
    • For more details, see the Essential Critical Infrastructure Workers list
  • Doesn’t Apply If:
    • If your home/residence becomes unsafe, you are permitted/urged to leave and stay at a safe alternate location (e.g. victims of domestic violence).
  • Doesn’t Apply If:
    • If you are an individual experiencing homelessness, but you are urged to obtain shelter, and governmental and other entities are strongly encouraged to do as much as they can to increase their capacity to help as many people as possible.

What Does This Mean for Gatherings?

Effective midnight on March 25, 2020 until midnight April 6, 2020 (unless extended beyond that date)

  • No public and private gatherings
  • Regardless of the number of people involved
  • doesn’t apply to people who are part of a single household or residential living unit.

What Does This Mean for Businesses?

All non-essential businesses in shall cease operations by midnight March 25, 2020 except for performing basic minimum operations.

All essential businesses are prohibited from operating unless they establish and implement social distancing and sanitation measures established by the United States Department of Labor’s Guidance on Preparing Workplaces for COVID-19 and the Washington State Department of Health Workplace and Employer Resources & Recommendations.

List of Links

CDC Situation Report – 60 Highlights on SARS-CoV-2

Solidarity Trial – International Study Being Organized

The first vaccine trial has begun just 60 days after the genetic sequence of the virus was shared by China. To ensure clear evidence of which treatments are most effective, WHO and its partners are organizing a large international study, called the Solidarity Trial, in many countries to compare different treatments.

WHO Health Alerts via WhatsApp

To increase access to reliable information, WHO has partnered with WhatsApp and Facebook to launch a WHO Health Alert messaging service. This service will provide the latest news and information on COVID-19, including details on symptoms and how people can protect themselves. The Health Alert service is now available in English and will be introduced in other languages next week.

To access it, send the word “hi” to the following number on WhatsApp: +41 798 931 892.

Virtual Concert Series

WHO and Global Citizen launched #TogetherAtHome, a virtual, no-contact concert series to promote physical distancing and action for global health. Chris Martin, lead singer of Coldplay, kicked it off earlier this week with a performance from his home. More Solidarity Sessions are planned to promote health, show support for people who are staying at home to protect themselves and others from COVID-19, and encourage donations to the COVID-19 Solidarity Response Fund.

Logistics or “The New Normal” of SARS-CoV-2

What to do, what not to do, what various levels of government are instructing us to do, and what you shouldn’t do just because you see other people doing it…


Governor Inslee’s Emergency Proclamation

Mandatory and immediate 2-week closure of all:

  • Restaurants
  • Bars
  • Entertainment facilities
  • Recreational facilities

Restaurants can still provide:

  • ✓ Takeout
  • ✓ Delivery

Dental Offices

  • All elective procedures are to be put on hold.
  • Offices should still see patients for dental emergencies or urgent dental care.

The American Dental Association (ADA) has called upon dentists to do their part to mitigate the spread of COVID-19 by postponing elective procedures for the next three weeks. For the ADA’s guidelines on what constitutes a dental emergency, please refer to this document.

Groceries/Household Supplies

Grocery stores and pharmacies are still open and there is no need to hoard supplies. Seattle’s supply chain is strong according to governor Inslee[edit: This was confirmed 3/19/20 by Greg Ferrara, President of the National Grocers Association], so please, be considerate of your neighbors and community and do not contribute to shortages – buy what you need right now.

Vulnerable Population(s) – Modified Shopping Hours

QFCSeniors (60+)
And other at-risk customers, as defined by the CDC
7 – 8 a.m.
Pregnant women
Individuals with compromised immune systems
Tuesdays & Thursdays 
7 – 9 a.m.
Stop & ShopSeniors (60+)
Individuals with compromised immune systems
6 – 7:30 a.m.
Individuals with compromised immune systems
First hour of each wednesday (check local store hours here)
UwajimayaSeniors8 – 9 a.m.
WalmartSeniors (60+)1 hour before store opens, typically 6 a.n. – 7 a.m.
(check local store hours here)
Every Tuesday from March 24 to April 28
Whole FoodsSeniors (60+)1 hour before store opens to public (check local store hours here)

Social Distancing/Events

Health Officer Order (Dr. Jeff Duchin, Department of Public Health – Seattle & King County)

  • All events with > 50 people are prohibited until further notice
  • All events with < 50 people are discouraged and prohibited unless organizers observe COVID-19 prevention measure requirements.
  • All bars, dance clubs, fitness and health clubs, movie theaters, nightclubs, and other social and recreational establishments shall be closed until at least March 31.
  • All other retail – including banks, grocery stores, hardware stores and pharmacies – should and may remain open, provided they observe COVID-19 prevention measures.
  • For more info, head here.

From the White House

President Trump recommended avoiding gatherings of more than 10 people and also urged Americans to avoid eating and drinking at bars and restaurants.



Uber and Lyft have suspended shared/pool rides.

Buses and Lightrail

In order to adhere to social distancing guidelines, until further notice, fare enforcement inspectors will not ask for proof of payment on board Link light rail or Sounder trains.

Buses and the Lightrail are increasing efforts to sanitize and keep cars/buses clean.

Utilities (Gas, Electricity, Water)

Residential Evictions in Seattle have been Halted During this Outbreak

Residential evictions for non-payment of rent have been temporarily halted. For more information, you can access this FAQ.

Utilities will not be Shut Off

Seattle Public Utilities (SPU) , Seattle City Light (SCL), and Puget Sound Energy (PSE) will keep utility services on during the COVID-19 Civil Emergency in Seattle. 

  • SPU and SCL customers who have been financially impacted by COVID-19, regardless of background or immigration status, can request a deferred payment plan that includes reversed late fees.
  • SPU and SCL recommends that customers should as soon as possible call (206) 684-3000 or send an email anytime at
  • PSE is waiving late fees for customers. You can find more information at PSE’s COVID-19 Response page.

CIty of Seattle Utility Discount Program (UDP)

The Utility Discount Program (UDP) lowers Seattle City Light bills by 60 percent and Seattle Public Utility bills by 50 percent. To learn more about enrollment in UDP, call (206) 684-0268 or go to:

Out of Work Employees/Artists

COVID-19 & Freelance Artists

From the site: “This list is specifically designed to serve freelance artists, and those interested in supporting the independent artist community. This includes, but is not limited to, actors, designers, producers, technicians, stage managers, musicians, composers, choreographers, visual artists, filmmakers, craft artists, teaching artists, dancers, writers & playwrights, photographers, etc.” Visit to see the full list of regularly updated resources.

COVID-19 LGBTQI+ BIPOC Mutual Aid Fund

This online fundraiser is to specifically support “queer, transgender, non-binary and/or intersex Black, Indigenous folks and other LGBTQI+ people of color (QTIBIPOC folks).” To donate to the fund, go here: To apply for funding, visit:

Financial Support for Seattle Artists Impacted by COVID-19

Seattle-based author and artist Ijeoma Oluo and others have organized this fundraiser on behalf of Artists Relief Fund. From the website: “This fund is aimed at helping those in the greater Seattle arts community who have been financially impacted by cancellations due to COVID-19, with priority given to BIPOC artists, transgender & nonbinary artists, and disabled artists – but we will try to help as many artists with need in Seattle as we can.” To donate to the fund, go here: To apply for funding, visit:

Seattle Restaurant Workers Coronavirus Rent Fund

Currently, the Seattle Restaurant Workers Coronavirus Rent Fund is accepting donations to support restaurant workers in Seattle who have been impacted by the COVID-19 outbreak. The hospitality industry nonprofit Big Table will be disbursing funds soon. To donate to the fund, go here:

Paid Sick and Safe Time

Both Seattle’s Paid Sick and Safe Time (PSST) Ordinance and Washington Initiative 1433 establish local and statewide paid sick leave for hourly employees working in Washington state. In Seattle, the law requires employers to provide all employees with paid sick and safe time. This includes full-time, part-time, temporary, exempt, and non-exempt employees. Please call the Seattle Office of Labor Standards at (206) 256-5297 or visit Office of Labor Standards PSST page here.

State Unemployment Benefits for Workers

The Washington State Employment Security Department has programs designed to help individuals and employers impacted by the COVID-19 outbreak. They have an easy-to-read comparison guide listing some of the most common scenarios that may occur and benefits that may apply. More information for workers and businesses here:

Washington Small Business Development Center Business Resiliency Toolkit

The Business Resiliency Guide is a tool to help small business owners assess risks and make contingency plans that will enable businesses to recover from the immediate threat of COVID-19 as well as the disruptions that could continue over weeks or months. You can download the business resiliency guide and supporting materials here:

Seattle Office of Arts & Culture

Arts & Culture has developed this additional resource list for artists and arts organizations impacted by COVID-19: Resources for Artists and Organizations Amid COVID-19.

Seattle Office of Economic Development (OED)

OED has updated their pages to include COVID-19 information for both businesses and workers: COVID-19 Business and Worker Resources

Seattle Office of Labor Standards (OLS)

OLS has compiled a comprehensive list of resources and FAQs for both workers and employers affected by COVID-19:

Small Business/Non-Profit Help

City of Seattle B&O Tax Deferment Information

Effective immediately, the City of Seattle Department of Finance and Administrative Services (FAS) will defer business and occupation (B&O) tax collections for businesses that have annual taxable incomes of $5 million or less and that pay city taxes quarterly. This will allow small business owners increased flexibility during a period of financial duress caused by the COVID-19 outbreak. If you have questions, please call (206) 684-8484 or email:

City of Seattle Small Business Stabilization Fund

Approximately $2.5 million is available for the City of Seattle Small Business Stabilization Fund, an emergency fund that provides working capital grants in amounts up to $10,000 to qualifying small businesses. Eligibility criteria and how to apply is here:

Financial Resources for Washington Residents Impacted by COVID-19

The Washington State Department of Financial Institutions has developed a list of financial resources for Washington consumers impacted by the Coronavirus. You can find more information about how to manage your mortgage, rent, and personal finances at their website:

Financial Support for Non-Profit Organizations Impacted by COVID-19

Hosted by Seattle Foundation, the COVID-19 Response Fund will provide flexible resources to organizations in our region working with communities who are disproportionately impacted by coronavirus and the economic consequences of this outbreak. The Fund is designed to complement the work of public health officials and expand local capacity to address all aspects of the outbreak as efficiently as possible. To donate to the fund, go here:

Resources for Unemployed Workers from United Way of King County

The United Way of King County has put together a list of resources for workers who have been laid off due to the COVID-19 outbreak. This list includes links to unemployment benefits, health insurance, and other free and reduced programs in and around King County. Go to the United Way of King County’s page for more information.

State Benefits for Employers

The Washington State Employment Security Department has programs designed to help individuals and employers impacted by the COVID-19 outbreak. They have an easy-to-read comparison guide listing some of the most common scenarios that may occur and benefits that may apply. More information for workers and businesses here:

Seattle Office of Labor Standards

More information about City of Seattle support for workers and employers can be found here.

Small Business Adminstration Economic Injury Disaster Loans

In addition, small businesses in Seattle and King County are now eligible to apply for up to $2 million in low‑interest Small Business Administration (SBA) Economic Injury Disaster Loans (EIDL) to offset economic losses because of reduced revenues caused by the impact of the Coronavirus (COVID-19) pandemic. With currently $1 billion in loan subsidies available from the federal government, the City’s Office of Economic Development (OED) will be offering technical assistance and launching resources to help small businesses apply for SBA loans.

Eligible small businesses can receive loans of up to $2 million to pay fixed debts, payroll, accounts payable and other bills that can’t be paid because of the impact of COVID-19. Small businesses, private nonprofit organizations of any size, small agricultural cooperatives and small aquaculture enterprises that have been financially impacted as a direct result of COVID-19 are eligible to apply.

Applicants for the federal SBA may apply online, receive additional disaster assistance information and download applications at

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Resources: SARS-CoV-2 and COVID-19

What to do if you have symptoms of coronavirus disease 2019 (COVID-19) and have not been around anyone who has been diagnosed with COVID-19

What to do if you have confirmed or suspected coronavirus disease (COVID-19)

National Institutes of Health (NIH) – Vaccine Research Efforts on Coronavirus (COVID-19)

Schools/Education – For updates on school closures and information and guidance for parents

Employment Security Department of WA State – Links and FAQs for workers and businesses affected by coronavirus

Business and Workers – Links and FAQs for workers and businesses affected by coronavirus

Retail businesses guidelines from Department of Public Health

Workplace Practices – handwashing and social distancing recommendations for employers

Have general questions? Comments?

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