The importance of having a certified N95/N99 filter in your face mask!

We would like to give you a better idea about what kind of pollution masks you should buy. And whether the mask will be fit for the purpose. For that, I will give a short introduction about N95 face masks. Followed by a description of how an N95 and/or N99 filter is built. And lastly, an explanation of what is the use of the activated carbon cotton in the filter. In the interest of simplicity, I will use the word “filter”. This will include both, or, as a matter of fact, any filter that contains activated carbon.


What is actually an N95 mask?

N95 stands for nothing else than a percentage number. In our case, N95 means that at least 95% of the particles are being filtered out while breathing through the mask. The particle sizes that are being filtered out are defined behind the letters ‘PM’ (= Particulate Matter), ie. PM 10, PM 2.5 or PM 0.3. At the time of writing, these are the available filtering efficiencies available. The title of the product should mention the particle size (eg. PM 10) after the filter efficiency (eg. N95). Stay away from any mask that does not provide a sufficient protection. For example, a mask which does not come with a certified filter.

Masks with a filter efficiency of at least 95% are used to safeguard your health from the adverse impacts of air pollution, dust, and smog. But these masks can also used to prevent spreading of flus or influenza such as swine flu, avian flu, bird flu, or any other airborne disease. They help protecting the wearer of the mask as well as the surrounding people to not spread or contract the flu, respectively. Ensure to regularly wash your mask if you use it for the latter purpose. It removes the bacteria from the cloth.


What are the different layers of an N95 filter?

Mainly, there are 3 components to manufacture an effective activated carbon cotton filter.

The outer layer consists of a melt blown fabric layer and a melt blown cotton layer. Both layers are tightly knit. And foremost, these two layers combined are providing a very comfortable feeling on your skin. The cotton layer also ensures that the bigger particles, such as PM 10 or thicker (for more details, see our other blog), are already being filtered out. You can see the grey or black matter on the filter while removing it from the mask.

The inner and most important layer is the activated carbon cotton (aka active carbon cloth). The carbon, or coal, is treated in a specific way (for simplicity, let’s keep it simple here!) to increase its adsorptive* power. Adsorption is the chemical process where particles will be trapped by the molecules in the activated carbon cloth. Without such a specific filter, your mask is actually useless; the fine particles will go through regular cloth as if there is no filter at all. This is measured in the carbon filteringefficiency which we will explain in a matter of a second.


How is an N95 filter different from an N99 filter?

Depending on the treatment of the carbon, the filter will remove more or less particles from the air. In an N99 filters, the activated charcoal molecules have a bigger surface area. So, these filters can capture more air pollutants (at least 99%). And hence you will breathe at least 99% less air particles than if you do not wear a mask. As follows, the N95 filter has smaller molecules. So they will be able to filter a slight bit less than an N99 filter, eg. 95%.

Now, N99 filters can usually trap a few more molecules since the surface of the area of the molecule is bigger (= to trap more air pollutants). And that is exactly the reason why you won’t be breathing in as many molecules as with an N95 filter or with no filter at all. But then N99 filters are more complicated and expensive to produce. So, be prepared to pay a slight bit more for a mask with an N99 filter. Your health should be worth it though, no doubt.

Having said that, it is not important to get the one or the other filter efficiency. The utmost value to you is that you have a certified filter at all, either of the two. But if someone has a serious health condition  already, or even had a heart attack, then it’s advisable to use an N99 filter. A person who is already negatively affected by the air pollution has to increase their protection to the maximum possible. And in this case, this is an N99 filter mask.


What is the impact on you if you DO NOT use a certified filter?

Well, from what we discussed so far, it should have become obvious to you that any certified filter is of immense value to you and to your loved ones.

Let us assume that you wear a surgical mask or a cotton cloth around your mouth while walking on the streets or riding your motorcycle. How much of the fine particles, eg. PM 2.5 and smaller, will be filtered before the air (and the particles therein) you breathe enters your body? The filtering efficiency is close to zero! For more details on that, please read our other blog. While reading the article, you can be certain that you will get shocked by the sheer amount of particulate matter you are inhaling with every breath.  And you will understand that living in a polluted environment is not all that healthy, to say the least.

If you are using N95 filters, at least, the chances for you to contract any of sicknesses and diseases, are diminished significantly. If you can choose to breathe cleaned air (filtered at least of 95% of the fine particles) or have your body absorb every particle in the air, I can only suppose that you would choose the earlier. For your sake and for your loved one’s sake, there is actually no choice to make but only a decision to take: which effective mask to purchase and at what price?


I hope this blog helps you to understand more about the effectiveness of masks with proper filters. Try not to get ripped off in the online market. There are unfortunately many sellers who promise the world and deliver only the trash of it.


Let us know your feedback below. We are very happy to hear your comments.



* For all the ones who always wondered what the difference is between absorptive and adsorptive. Adsorption is the process where ions, molecules or atoms are adhering to a surface rather than having a fluid being absorbed or dissolved by a liquid or solid. (See Reference).

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