Understanding mask ratings can seem overwhelming at first, especially if you live in a country where the knowledge isn’t commonplace. Understanding the difference between an N95 and R95 respirator alone is difficult, and that’s not to mention the many different rating systems!
I myself knew little about respirators before moving to Korea. Here, they are essential on days of bad air pollution in Seoul, and it’s important to have at least a basic understanding so that you are able to protect yourself.
After spending days researching for articles on this website, I have come to learn a lot about respirators and masks. In that time, I have also come to realise how little most people know about them and the differences between the rating systems.
Further, with the recent panic around the world, masks are in more demand than ever. However, a lot of people are having difficulty comparing masks and making the right purchasing decisions.
In this post, I will compare the different rating systems, and point out what you need to know. By the end of this post, you will be able to make an informed purchasing decision and to know that you are getting the best mask for your needs.
This article was created to help you answer the question of ‘what are the differences between N95, FFP2, KN95, KF94 and other mask ratings?’. Further, what are the similarities between the systems? Read on to learn more.
Masks are only effective when fitted and worn correctly. Please refer to this CDC guide to donning a respirator for more information.
Disclaimer: I am not a doctor or an expert on masks. I wrote this post after doing extensive research online, and all of my sources are listed. If you find any errors or have any questions, please feel free to contact me.
This post contains affiliate links. For more information, read my affiliate disclaimer.
Mask Rating Systems
‘Respirators with similar performance requirements to NIOSH-approved devices’ (CDC). However, there is still limited testing on these standards by CDC, and N95 is recommended where possible.
The biggest factor that makes understanding mask ratings so difficult is the number of different systems. The most commonly known mask rating is the NIOSH system, which rates masks as N95, N99, and N100. These masks are rated by the American National Institute for Occupational Safety and Health, which is part of the CDC.
But did you know that this is only the tip of the iceberg? Not only does the NIOSH also certify R and P rated masks, but there are also 5 other commonly used mask rating systems. Although knowing the NIOSH rating system is normally enough, in times when stocks are low knowing the other mask ratings can come in handy. After all, N95 masks are usually the first to sell out.
The most important rating systems to know are the NIOSH ratings (N95), and Europe EN (FFP2). These are the most commonly found masks and most other rating systems are based on, or closely follow, the guidelines of these respirators.
The other rating systems are the Korean KF ratings given by the MFDS (Ministry of Food and Drug Safety), Chinese KN and KP ratings given by the Standardization Administration of China, New Zealand & Australian P ratings given by the Joint Australian/New Zealand Standards Committee, and Japanese DS ratings given by the Japanese Ministry of Health, Labour, and Welfare.¹
In this article, I will be looking into all of these different ratings and what they mean. In the end, there will be a comparison of the masks, and information on which is best.
Respirators are only rated for one use (typically of 8 hours). However, in times of need, they can be disinfected and reused. Learn more about respirator cleaning here.
U.S NIOSH Ratings
NIOSH masks should always have the above markings. CDC.
NIOSH rated masks are the most common masks that you will usually find. These masks come in three different letter variations, N, R, and P. These letters will be followed by a number, making a rating such as N99, R95, or P100. But what do these letters and numbers mean?
Luckily, the number is easy to understand. The number on a NIOSH rated masks signifies the filtration effectiveness of the filter. For example, an N95 mask is required to stop AT LEAST 95% of particles of 0.3 microns in size.² An R95 mask will also filter out at least 95% of 0.3-micron particles.
The only difference comes in with N100 and P100 rated masks. Complete filtration is at this point impossible, and a 100 rated mask is effective at stopping 99.97% of 0.3-micron particles.³
In other words, the higher the number the better the filtration efficiency. To be put even more simply, the higher the number, the better. In terms of filtration, the letter before the number doesn’t matter – an N100 and P100 mask are rated to filter the same percentage of particles. The same goes for N95 and R95 masks.
N vs R vs P respirators
The letters on NIOSH rated respirators represent the oil resistance of the mask. N rated masks are not resistant to oil, R rated masks are somewhat resistant to oil, and P rated masks are strongly resistant to oil.³
This means that for people wearing masks due to air pollution or viruses, only an N rated mask is needed. R rated masks can come in useful in specific situations, for example, if you bike on the road close to vehicles often. An R rated mask will be more resistant to the fumes put out by those vehicles.
For the vast majority of people, N rated masks are all that is needed. R and P rated masks are generally used in workplaces that involve aerosols and that need to provide workers with the best protection.⁴
European EN Ratings
EN149:2001 FFP3 Respirator from 3M.
The next most common masks that you will find are those rated by the European Union. These masks come in three different ratings, FFP1, FFP2 and FFP3. Although the numbers on these masks don’t follow the same system as the NIOSH masks, the higher numbers are still better.
An FFP1 mask has 80% filtration, FFP2 has 94% and acts very similarly to an N95 mask, and FFP3 has 99% and performs similarly to an N99 mask.⁵ In short, other than the FFP1 rating, which performs significantly worse than any NIOSH rated mask, European EN rated masks perform similarly to their NIOSH equivalents.
When picking a mask for fine dust or other very fine particles, an FFP2 or FFP3 mask is highly recommended as they will perform substantially better against fine particles in the air.
Chinese KN and KP Ratings
A Chinese rated KN95 Respirator. This is the Xiaomi Purely fan-powered mask.
Chinese masks come rated as either KN or KP. Similarly to the NIOSH ratings, the letters represent oil resistance while the number represents filtration efficiency. KN and KP masks come rated as 90, 95, and 100.
KN masks are the standard masks that are intended for the vast majority of wearers. These masks are not resistant to oil. KP masks, on the other hand, do provide oil resistance. KN and KP masks are both available in 90%, 95% and 100% (100% is actually 99.97%) varieties.⁷
Unfortunately, specific information on these masks is very difficult to find in English. However, going from the comparisons later in the article, they do appear to perform similarly to their comparable masks from other mask rating systems.
Learn More: MeoAir Reusable Respirator with 99% filtration efficiency.
Korean KF Ratings
A standard KF94 rated mask.
Korean KF rated masks come in two different levels, KF80 and KF94. Like the NIOSH system, the number represents the filtration rate of particles, and this makes the masks very easy to compare. For example, a KF80 mask will filter 80% of particles at the MPPS.
The KF system is based on the European FFP rating system and as such, it performs almost identically. A KF80 mask performs the same as an FFP1 mask, and KF94 will perform the same as an FFP2 mask.⁶
If possible, use KF94 masks where possible, as they have significantly more protection than KF80 masks. In Korea, KF80 masks are often aimed at children and KF94 at adults.
Australian & NZ P Ratings
An Australian/New Zealand rated P2 Mask. Queensland Government.
P ratings are given by the Australian and New Zealand governments and are a bit harder to understand than most other systems. These masks can come rated at three different levels, P1, P2 and P3. As usual, the higher the number, the more effective the mask is. From the 3M website, these are the uses for each mask.
- P1 – used for mechanically generated particles eg silica, dusts, powders.
- P2 – used for mechanically and thermally generated dusts eg welding fume, metal fume.
- P3 – used for all particulates requiring high protection factors.⁸
For fine particles, a P2 mask will perform similarly to an N95 mask. The New South Wales Government even calls a P2 respirator an N95 mask. The comparison tables further in the article also go on to support the P2 mask being similar in performance to an N95 mask.
For this reason, when it comes to fine particles, a P2 or P3 mask is recommended. These masks will perform similarly to the European rated FFP2 and FFP3 masks.
Japanese DS Ratings
The final commonly-used mask rating on this list is that issued by the Japanese Government. Similar to many of the other ratings on this list, the Japanese rating system follows the FFP system used by the European Union.
Japan rates masks as DS, DL, RS and RL followed by a number. 1 represents 80% efficiency, 2 is 95% and 3 is 99.9%. That is to say, a DS1 and RL1 mask have 80% efficiency against fine particles, an RL2 mask would have 95% efficiency, and an RS3 mask would have 99.9%.
The different letters represent aerosols that were tested with the masks. ‘Count median diameters of these test aerosols are ranging from 0.06mm to 0.10 mm for NaCl aerosol and from 0.15 mm to 0.25 mm for DOP aerosol. The test flow rate for the challenge aerosol (85 l/min) is similar to the NIOSH standard. The levels of collection efficiencies with dust loading are more than 80%(DS1, DL1, RS1 and RL1), 95%(DS2, DL2, RS2 and RL2)and 99.9%(DS3, DL3, RS3 and RL3) for both of NaCl (DS and RS) and DOP (DL and RL)’.⁹
Since NaCI aerosol is of a smaller size, the DS and RS masks perform slightly better in regards to fine particles than the other ratings. However, information (in English) is limited on the Japanese rating system, so I can’t confirm this.
Which Mask Rating is Best?
Now that we have covered the different mask ratings, it’s time to compare them and to see which is the best. Obviously, the best mask depends on the situation, however, for this section I am using the assumption that you don’t need an oil-resistant mask. Further, I am assuming that the mask is being used for standard particles, such as fine dust (as opposed to viral particles or otherwise).
There is no single ‘best’ rating. N masks are not inherently better than KF masks, for example. As the table from 3M below shows, every different rating system has a comparable mask around the 95% filtration bracket.
As the table above shows, every system has a mask that provides around 95% filtration. Not all mask systems offer masks higher (Korea has its highest rating at KF94), however, the 99.97% filtration masks from the different systems are also comparable.
It’s important to realise that any mask rating is better than none. A mask with any rating on this list will perform better than a standard surgical mask. Further, each rating system has a range of levels, often with 3 different tiers.
If you want the absolute best respirator, look into those with a rating around 100%. This means N99, FFP3, KN100, or any comparable mask. Even a P100 mask is an option if you don’t mind spending a bit more.
Respirators with a rating similar to N95 also work very well. Masks such as KF94, FFP2, P2, and KN95 are all great options and provide good protection against fine dust and other small particles.
Read more: Xiaomi Purely mask review
Mask Rating Comparisons
When comparing the specific ratings, there are three main brackets. 80% (KF80, FFP1, etc), 94-95% (KF94, FFP2, N95, etc) and 99-100% (N99, P100, FFP3, KN100).
The graph below is a fantastic example of the different respirator brackets and how they compare. The dots on the lines represent individual respirators that were tested within each rating system. While the line does compare NIOSH and KFDA (Korea Food and Drug Association, now the MFDS), it’s important to remember that the KF system is based on the EU FFP system.
‘In Korea, since the EU standard was adopted, the efficiency requirements specified by the Korea Ministry of Labor (KMOL) for Second, First, and Special series are the same as the European requirements for FFP1/P1, FFP2/P2, and FFP3/P3, respectively’⁶
Since the Australian/New Zealand P2 rating is the same as N95, and KF94 is the same as FFP2, this graph can be applied to these different mask rating systems also.
KF80 vs FFP1
In the first bracket, we find KF80 and FFP1 rated respirators. However, there isn’t much difference between the two. Since the Korean mask rating system is based on that of the EU, these masks are identical in terms of specifications. Due to this, it’s better to pick whichever mask fits your budget and face better.
However, it’s important to remember that these masks are only rated at 80% filtration. Both KF80 and FFP1 masks are far less effective than those in the next bracket (94-95%)
N95 vs KN95 vs FFP2 vs KF94
The second mask bracket has a lot more options. It is worth noting again, that since KF94 respirators use the same specifications as FFP2 respirators, that this comparison is really between N95, KN95 and FFP2 respirators.
Both N95 and KN95 rated masks are effective at filtering out at least 95% of fine particulate matter. On the other hand, FFP2 masks are rated at 94%. For this reason, N95 and KN95 masks are very slightly more effective than FFP2 and KF94.
However, the difference is minimal and as the graph above shows, some FFP2 and KF94 masks can filter a significantly higher percentage of particles than 94%. If you are looking for certainty however, an N95 mask is the best.
KN95 masks from China should perform very similarly to N95 masks, and the table above shows that the differences are very minor. However, it’s very hard to find further information on KN95 masks in English. Further, it’s far easier to verify the authenticity of an N95 mask. For that reason, N95 masks are the best in this bracket.
N99 vs FFP3 vs KN100 vs N100
In the last, and highest-rated bracket, are the 99 and 99.97% filtration respirators. These are the best respirators that can be purchased and offer the best protection against microparticles.
N99 masks and FFP3 are comparable and both offer 99% filtration. ‘NIOSH requires a minimum of 95 and 99.97% efficiencies for N95 and P100 FFR, respectively; meanwhile, the EN requires 94 and 99% efficiencies for FFRs, class P2 (FFP2) and class P3 (FFP3), respectively.’¹⁰
However, N100 and KN100¹¹ respirators are both rated to filter 99.97% of particles at 0.3 microns, and this makes them more effective than FFP3 and N99 respirators.
This makes N100 and KN100 masks the best masks that can be purchased for general use.
Best N99 rated respirators – 3M N99 respirators
P100, R100 and KP100 Respirators
Half-face reusable respirator. Queensland Government.
The final respirators on this list are not for general purpose. These respirators are rated by the NIOSH (P and R) and the KP respirators are rated by the Standardization Administration of China. The difference with these respirators is that they are oil resistant.
R100 and KP100 respirators are oil-resistant and P100 are strongly oil resistant.³ All of these masks are rated for 99.97% filtration, similar to the non-oil resistant variants.
As all of the information above has shown, all mask rating systems have different tiers of respirators, and they all offer a variant that has at least 94% filtration. However, my research also shows that NIOSH masks tend to slightly outperform those of other rating systems with the exception of the KN and KP masks from China.
That isn’t to say that non-NIOSH masks are bad. There are many fantastic options, and any rated mask will provide better protection than an unrated mask. However, if you are looking for the best possible protection, N95 masks are slightly better than the other comparable masks, and so are N100 masks against their comparable options.
Further, N masks tend to be the easiest to verify the authenticity of. It’s far easier to tell what is an authentic mask, and what is questionable. Finally, but perhaps one of the biggest factors, is that NIOSH rated masks have the most available English resources. It’s easy to find information online about these masks, especially when compared to the mask ratings from east-Asia.
There are a lot of different respirators out there, and it can be very hard to pick one. It can definitely feel overwhelming at first! If you still don’t know which mask to purchase, I have listed a few good options here.
These masks are primarily N95, N99, or N100. These respirators are often believed to be the best, and after my research for this post, I agree. If you are wondering why I chose to recommend NIOSH masks, feel free to go ahead and read the above sections of this post!
N99 reusable respirators – Cambridge Mask (please note, this mask is NOT N99. However, it meets N99 filtration requirements).
With all of the confusion surrounding respirators, I hope that this post has clarified the rating systems and helped you to pick the right mask for your situation. I will be updating this article into the future and adding information where possible.
While respirators can protect the wearer from fine particles, it’s important to remember that they will only do so if they are fitted correctly and handled well. If you are unsure how to fit a mask correctly, please refer to this article by the CDC.
If you have any questions or have noticed any inaccuracies in this post, please don’t hesitate to reach out to me. You can do so either below, by commenting, or by emailing me at email@example.com.
Mask Rating FAQ
Are N95 and KN95 the Same?
No, these are two different rating systems. N ratings are given by the U.S NIOSH. However, KN ratings are given by the Standardisation Administration of China. However, both ratings do feature many similar characteristics.
Is FFP2 the Same as N95?
FFP2 rated respirators feature similar characteristics to the N95 rating, especially in regards to filtration. However, the ratings are used in different regions and do have some differences.
Why Are There So Many Different Ratings?
Many regions of the world have developed their own rating systems that meet the local market requirements. Further, some systems are aimed at specific sectors, whereas some are aimed at public use.
What Is the Difference Between N95, R95 and P100?
All of these masks are rated by the NIOSH. However, the difference comes down to oil resistance. N95 masks are non oil resistant, R95 masks are lightly-oil resistant, and P100 are oil resistant.
- 3M, Comparison of FFP2, KN95, and N95 and Other Filtering Facepiece Respirator Classes. https://multimedia.3m.com/mws/media/1791500O/comparison-ffp2-kn95-n95-filtering-facepiece-respirator-classes-tb.pdf
- U.S Food and Drug Administration, Masks and N95 Respirators. https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/masks-and-n95-respirators
- U.S CDC, NIOSH-Approved Particulate Filtering Facepiece Respirators. https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html
- U.S CDC, NIOSH Guide to the Selection and Use of Particulate Respirators. https://www.cdc.gov/niosh/docs/96-101/
- 3M, Respirators for protection against PM2.5. https://multimedia.3m.com/mws/media/1313143O/respirators-for-protection-agains.pdf
- Aerosol and Air Quality Research, Comparison of Filtration Efficiency and Pressure Drop in Anti-Yellow Sand Masks, Quarantine Masks, Medical Masks, General Masks, and Handkerchiefs. http://aaqr.org/files/article/668/36_AAQR-13-06-OA-0201_991-1002.pdf
- Int. J. Environ. Res. Public Health 2018, https://www.mdpi.com/1660-4601/15/11/2565/htm#B76-ijerph-15-02565
- 3M, Respiratory Protection – Basic Information. http://multimedia.3m.com/mws/media/473936O/respiratory-protection-basic-information.pdf
- ISRP 2002 abstract, New Standard for Dust Respirators in Japan. http://www.isrp.com.au/isrpcom/journal/ed_abstracts/abstract__myojo.htm
- US National Library of MedicineNational Institutes of Health, Comparison of nanoparticle filtration performance of NIOSH-approved and CE-marked particulate filtering facepiece respirators. https://www.ncbi.nlm.nih.gov/pubmed/19261695
- Fudan University, http://jmi.fudan.edu.cn/CN/article/downloadArticleFile.do?attachType=PDF&id=821