The use of face masks is something most of us have gotten used to during the pandemic, especially in the United States. A common question asked about them is which one is the best to protect against COVID-19, and also to prevent its spread to other people. Even before the pandemic was officially announced, it became a common activity to buy masks in bulk and wholesale, but now most of them are hard to find for sale.
A popular type of face mask being used are N95 masks with valves, and we can see them being used by a lot of people. However, not many of them know how they work, and that they’re not useful for COVID-19. This has led to them being banned on airplanes, and in this article, we’ll explain in detail why.
Understanding how COVID-19 is spread between people
Before we understand why valved N95 respirators have no use in the pandemic, we have to know how the disease is spread. This is a respiratory infection that can vary in its severity, from asymptomatic cases to ones that compromise the life of the patient.
However, the majority of the cases are either asymptomatic or mild, resembling the flu with the most common symptoms reported being fever, dry cough, sore throat, and muscle pain, sometimes accompanied by the loss of smell and taste. These cases can go unnoticed, and people can still spread the disease.
A group of people with some risk factors, like the elderly, immunocompromised patients, those with cardiovascular disease, obesity, diabetes mellitus, pre-existing lung conditions, among others, are more likely to develop a severe form of the disease. Kids and younger people, on the other hand, are the least affected age group. Life-threatening complications of the disease, such as thrombosis, severe lung injury that could require mechanical ventilation, and multi-organ failure, are much more likely to happen in these patients, and these could all lead to death.
Since this is a respiratory virus, it’s spread from one person to the other like many other respiratory viruses: through respiratory droplets. These contain the viral particles, which can land on the nose or mouth of the healthy person, and through them they can reach the airways, colonize them, replicate, and damage them in the process.
This is why the use of face masks and face-coverings can prevent the spread of the disease, since they cover up the mouth and nose, preventing the respiratory droplets from either landing on the face or being released into the air. For this reason, N95 masks, KN95 masks, surgical masks, and reusable cloth masks are all good options for virus control, and the CDC recommends everyone above the age of two to wear a face-covering, with or without face shields to protect the eyes as well.
Why exhalation valves are added to N95 masks and how they work
The Centers for Disease Control and Prevention (CDC) explain that exhalation valves, also known as vents, are added to N95 respirators to make them more breathable. This increases the comfort of the mask, and some users also say they’re cooler and prevent the fogging of glasses and eyewear. However, it’s important to understand how this is achieved.
A regular N95 mask will filter out the air in both directions: as it’s being inhaled and as it’s being exhaled. This prevents not only the protection of the wearer but also of the people around them, since the air the user exhale is being filtered and they can release pathogens into the air.
Exhalation valves reduce the breathing resistance by not filtering the air that is being exhaled. This is why they're also called a one-way valve, since they only filter the air in one direction as it’s being inhaled, protecting only the user from the particles in the environment and not the other way around.
This would mean that masks with exhalation valves won’t prevent the spread of the coronavirus, since they won’t prevent an infected person from releasing the virus into the air. A person can be asymptomatic and not be aware that they are spreading the disease, and with exhalation valves, they can do so easily.
For virus protection, the CDC has stated that these masks are not recommended. The antiviral filtering properties are only applied to the inhaled air, giving these masks other uses. For example, for the filtration of smoke and dust, they can be used since these environments don’t require the filtration of the exhaled air. The 3M 8511 is a 3M N95 mask with an exhalation valve, while the 3M 8210 and the 3M 1860 don’t have this accessory.
Which airlines have banned N95 masks with valves in their flights?
For the reasons listed above, several airlines in the USA have banned the use of masks with vents or valves in their flights. American Airlines was one of the latest to implement this measure, with their policies being updated on August 12, 2020, just days after the CDC changed their guidelines regarding the use of vented or valved masks for the prevention of spreading COVID-19.
Other airlines that have implemented this policy include Alaska, Delta, Southwest, Frontier, JetBlue, Spirit, and United. Additionally, Allegiant, Hawaiian, and Sun Country, along with the others mentioned, require all passengers above the age of two to wear a face mask. Delta, Hawaiian, Allegiant, and Sun Country make exemptions for medical conditions.
The USA, along with the rest of the world, is facing a difficult situation, so we want to urge our readers to not wear valved N95 masks for protection.