Last year was a very strange and difficult year, and among all the things we’ve learned, personal protective equipment is now something most of us are experts in. Often referred to by the acronym PPE, these products have been the center of attention and main topic of discussion due to the virus. Face masks have been particularly a big topic of discussion, as they’re the main method for virus control we’re implementing.
As expected, healthcare workers have been some of the most exposed ones to the dangers of COVID-19, which is why they need only the most effective pieces of PPE, which includes several layers for them to work safely, particularly when treating COVID-19 cases.
The minimum amount of PPE a healthcare provider needs includes gowns, gloves, face shields, N95 masks, and surgical masks. These items were easily found for sale online before the pandemic, and people could buy them in bulk and wholesale with no problem. Now, the demand has been so high, even healthcare centers struggle to obtain them.
There’s no doubt N95 respirators are the most widely discussed item among the PPE we mentioned, since their filtering properties have turned them into a valuable product in the healthcare field. But, a lot of people don’t know how they work, and are sometimes scared they won’t be able to breathe properly with them.
This article will focus on explaining how air is filtered through an N95 mask.
The name of these masks comes from a classification of respirators used in the United States to regulate these products. They’re considered disposable face masks, and offer very high antiviral filtering properties, which is why they surpass surgical mask, the most commonly used face mask in this industry, for virus protection in the healthcare field. Of course, they’re also a lot more efficient than reusable cloth masks, which are the ones recommended for the general public. Those masks should not be used in healthcare settings for protection against COVID-19.
The classification from which the name of these masks come is established by an entity known as NIOSH, which stands for the National Institute for Occupational Safety and Health. This federal agency is a part of the Centers for Disease Control and Prevention (CDC), and is in charge of issuing recommendations to workplaces in the USA with the goal of avoiding occupational illnesses or injuries.
Respirators are masks or mask-like devices that can filter out the air a person is breathing. They’re used as PPE in many different work settings that have all types of respiratory hazards present. These particles can cause serious health conditions on workers exposed to them, so respirators protect them by filtering them out and preventing them from inhaling them at work.
To name respirators in the classification, they take into consideration two characteristics:
Oil resistance: this is directly proportional to their efficacy to filter out oil-based particles. A letter is assigned to indicate these: N means not resistant, R means somewhat resistant, and P means oil-proof.
Filtration efficacy: this is represented by a number in the name: 95, 99, or 100, and they’re the percentage of minimum particulate filtration efficacy, which tells us the number of airborne particles (those with a 0.3 micrometer size) the mask can filter out.
We can conclude after reading this explanation that N95 masks have no oil resistance and a filtration rate of 95%. This translates into the ability to filter out 95% of the airborne particles in the air that don’t contain oil. This includes a wide range of particles considered respiratory hazards in different work settings.
For example, in construction or mining sites, we can find dust, firefighters can encounter smoke, gardeners are constantly exposed to pollen, and healthcare workers have bioaerosols as threats, like the flu virus or, most recently, the novel coronavirus. These are all non-oil based airborne particles, and therefore N95 masks have a wide range of uses.
Since NIOSH establishes the requirements for these respirators, N95 masks and other respirators contained in the classification have to be approved by them after being tested to make sure they can be sold as that respirator type.
So, if a manufacturer produces N95 masks and want to market them as such, NIOSH has to first evaluate them and grant their approval. N95 masks used in the healthcare field specifically represent a medical device, which requires regulation from the Food and Drug Administration (FDA), so these masks need approval from both entities.
People often confuse N95 masks with KN95 masks, and many think they’re the same mask. This isn’t true simply because KN95 masks are manufactured and regulated with a different standard used in China. Even though they’re very similar to the NIOSH ones, they have some differences, and should not be considered the same. However, KN95 masks also offer 95% filtration rate for non-oil based airborne particles.
N95 respirators have a filter material inside of them. This material is known as a non-woven fabric or melt-blown material, which is the result of putting polypropylene or other types of plastic through a series of processes. The end result is a fabric with multiple tiny holes in it, which are meant to trap and filter out very small particles. Additionally, some N95 masks contain electrostatic charges in their filter media to enhance the filtration by attracting and trapping particles with the opposite charge.
Some of the most reputable brands when it comes to N95 masks include Honeywell and 3M. The most popular 3M N95 mask models include the 3M 8210 and the 3M 8511 for industrial uses, and the 3M 1860 as a surgical N95 mask.