What’s the Difference Between N95 and KN95 Masks? (KN95 vs. N95)

Is KN95 same as N95? With such similar-sounding names, it can be confusing to understand the difference between N95 and KN95 masks. This handy chart explains the similarities and differences between N95 and KN95 masks. 

N95 vs. KN95 Comparison Chart

Source: 3M – Comparison of FFP2, KN95, and N95 and Other Filtering Facepiece
Respirator Classes

In short, N95 masks are the US standards for respirator masks; KN95 masks are the Chinese standards for masks.

WATCH: What’s the Difference Between N95 and KN95?

What's the difference between N95 and KN95 masks?

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According to mask manufacturer 3M, “it is reasonable to consider” China’s KN95s “equivalent” to US N95s. Mask standards for Europe (FFP2), Australia (P2), Korea (KMOEL), and Japan (DS) are also very similar.

Australia P2 Mask Standards similar to N95 and KN95 masks

N95 vs. KN95: What’s the Same?

Lots of users care most about what percentage of particles the masks capture. On this metric, N95 and KN95 respirator masks are the same. Both masks are rated to capture 95% of tiny particles (0.3 micron particles, to be exact).

Differences Between N95 and KN95 Masks standards

Since N95 and KN95 masks are rated to capture 95% of 0.3 micron particles, people will often assume that masks can’t capture particles smaller than 0.3 microns. If that was true, then it wouldn’t make sense that masks do a really good job of preventing virus transmission.

N95 masks can capture and filter viruses, reducing virus transmission

The crazy reality is that particles smaller than 0.3 microns are actually easier to capture. Don’t believe us; believe the data. Here’s the science behind it »

Difference Between N95 vs. KN95 Masks

Both ratings require masks to be tested for filtration efficiency at capturing salt particles (NaCl). Both are tested at a flow rate of 85 L/minute. However, there are some differences between N95 and KN95, highlighted here.

KN95 vs. N95 – Differences Highlighted

Difference Between N95 and KN95 Masks Highlighted

Most of these differences are small and would be uninteresting to the average mask user. However, here are the key differences:

1. To be certified as a KN95 mask, the Chinese government requires the manufacturer to run a special mask fit test on real humans with ≤ 8% leakage. The N95 mask standard does not require manufacturers to run fit tests.

This does not mean that fit tests aren’t helpful. Many hospitals and companies require their workers to be fit-tested. However, those are requirements of companies themselves, not for the US NIOSH certification on the mask.

Read more: Comparison of Mask Ratings, Standards, and Filtration Effectiveness (N95, KN95, FFP1, FFP2)

Mask fit test requirements KN95 vs N95

2. N95 masks have slightly stricter requirements for pressure drop while inhaling. That means they’re required to be slightly more breathable than KN95 masks.

Don’t worry, despite it sometimes feeling difficult to breathe through masks, dying from oxygen starvation is very unlikely when wearing a mask.

3. N95s also have slightly stricter requirements for pressure drop while exhaling, which should help with breathability.

Some N95 Masks Tested Fail Standards

Smart Air tested 31 N95 masks on the market coming from China. We used a wind tunnel and Met One particle counter to see how many particles were getting through each mask.

Smart Air N95 mask test setup wind tunnel

13 out of 31 masks did not meet the N95 standard, many far below.

13 out of 31 masks failed to meet N95 standard

When purchasing a KN95 or N95, note that not all mask brands are of equal quality. Sticking to reputable brands such as 3M can help better ensure the mask actually meets the KN95/N95 standard.

Read more: 3 Steps to Find Authentic KN95 Masks and Avoid Fakes

DIY N95 Mask?

N95 masks are one of the best-performing masks on the market, but they come at a higher cost compared to surgical masks and have seen shortages in the past. So can you make your own DIY N95 mask? A recent study showed that simply using rubberbands to improve the fit of surgical masks can improve a surgical mask’s performance to the N95 standard.

Bottom Line: Difference Between N95 vs. KN95 Masks

N95s and KN95s are both rated to capture 95% of particles. Among the minor differences, only KN95 masks are required to pass fit tests, while N95 masks have slightly stronger breathability standards.

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N95 Masks India Delhi

Availability of N95 and KN95 Masks

The availability of N95 and KN95 masks can vary greatly depending on location. In the United States, KN95 masks are far easier to get your hands on than N95 masks. The reason is KN95 masks do not meet the NIOSH standards for face masks, so hospitals and healthcare facilities can only use N95 masks. For this reason, N95 masks may be reserved for healthcare workers, leaving a larger supply of KN95 masks for the average consumer. This does not mean the KN95 masks are inferior, as long as they are genuine KN95 masks.

CDC Update (2022): N95/KN95 Masks and Omicron

The more contagious COVID-19 omicron variant has put a spotlight on more effective masks such as N95 and KN95 masks. In January of 2022, the CDC updated their masking guidelines stating respirators such as N95 and KN95 “offer the highest level of protection”. The CDC also clarified that people can use these respirators for regular use and that there is little supply shortage concern like previously.

Learn More About N95 and KN95 Masks

Wondering how to wash a KN95 or N95 mask? Read more on the most reliable way to wash and disinfect your KN95 or N95 mask »

Check out the full US Code of Federal Regulations for N95 (and also N99, N100 masks).


WHAT NEXT?

Along with wearing masks, air purifiers with HEPA filters are also one of the best ways to stay safe from a variety of pollutants in our air including viruses and dangerous PM2.5. A recent CDC study confirmed significantly lower COVID-19 infection rates in schools that used HEPA air purifiers. HEPA filters can significantly lower the risk of a variety of deadly diseases including diabetes, heart disease, cancer, and high blood pressure.

Read More: Four Steps to Choosing the Best Air Purifier

Smart Air is a certified B Corp committed to combating the myths big companies use to inflate the price of clean air.

Experience breathing truly clean air with gimmick-free, effective air purifiers that won’t break the bank. Join the clean air movement.

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152 thoughts on “What’s the Difference Between N95 and KN95 Masks? (KN95 vs. N95)”

  1. It is important to note that both N95 and KN95 masks should be worn properly in order to be effective. The mask should fit snugly against the face, and there should be no gaps around the edges. The mask should also be replaced every 8 hours or sooner if it becomes dirty or wet.

    Reply
  2. The main difference is that N95 masks are certified by the National Institute for Occupational Safety and Health (NIOSH) in the United States, while KN95 masks are certified by the Chinese government. Both certifications require the masks to meet similar standards for filtration efficiency, but there may be slight differences in the testing methods and requirements.

    Reply
  3. I love that your testing facility looks like it is set up in your college dorm room. Kudos, though, as you appear to be careful about it.

    Reply
    • Sorry to correct you but, the N-95 is a US Standard but is made in the US and China. The KN-95 is a China Standard.

      Reply
  4. I complain as much as everyone else about breathing in the masks but my main complaint is that they my glasses fog up continually. I also play a sport called squash on a private school’s courts who demands that all people wear both goggles and masks. It takes 30-40 minutes that my plastic goggles have warmed up enough to stop fogging while running on the court.
    Does anyone know which of the mask causes less fogging?

    Reply
  5. I get a headache everyday. Once I get in my car and remove my mask the headache begins to go away. Within an hour no more headache. Is this because I am wearing a mask for 7 hours straight? That is with a cloth mask or a blue disposable mask. Now they are requiring us kn95 or n95 masks. The other masks are not allowed anymore. Is it safe to wear these heavy duty masks for 7 hours?

    Reply
    • It could be because the mask is uncomfortable for you. If you live in a polluted place, it’s actually possible that by getting in your car you’re breathing cleaner air than outside the car. Our tests show that cars are actually very good air purifiers. N95 masks were originally designed for industrial workers to wear in dirty, polluted factory environments. These workers would typically wear N95 masks for a whole shift. However, it’s important to try and find a mask that’s comfortable and fits your face well. This may have a big impact on whether you get a headache or not.

      Reply
  6. A recent study enlisted in the South African Medical Journal states that KN95 masks have failed tetsts deeming it unsuitable for lab use with exposure to TB and Covid 19. Please verify.

    Reply
  7. Effectiveness of different Masks commercial and medical mask and evidence behind it view to physical chemical and biological / scienticic properties as to usage behind them.

    Reply
  8. I see folks N95 wearing masks with the plastic valve fitted in front, which allows easy exhalation, intended for working in non-microbial work environments.

    I think this is a great article but it should note and show these valves types of masks, which provide some infection protection for the wearer but none for others nearby.

    Reply
    • Original N95 (with valve for breathing out) we bought 5 years ago in fire area for fire protection are from a welder’s supply shop, for welders; not for wearing with COVID 19 and we have read not to wear the valve type of mask for COVID-19 protection.

      Reply
      • That’s right, Sharen. N95s can come in two forms: with a valve, and without a value. The N95s with valves make them easier to exhale through, so are useful when doing heavy physical labor. However, like you said they are not recommended for COVID-19 protection. They will protect the wearer from breathing in virus particles from other people. But they will not stop the wearer breathing out virus particles onto other people (if they are infected).

        Reply
        • I want to point out that the CDC acknowledges that N95s with exhale valves provide source control on par with surgical or cloth masks. Per the CDC “As source control, findings from NIOSH research suggest that, even without covering the valve, N95 respirators with exhalation valves provide the same or better source control than surgical masks, procedure masks, cloth masks, or fabric coverings.” source: https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html This is based upon experimental testing and has been known since 2020, but the CDC has just now updated their guidance to acknowledge this.

        • Thank you Eugene, I just want to add: Dr. Richard Urso, MD, has reportedly reviewed the medical respirator literature, and concluded N95s (KN95s) are not sufficient to protect against viruses with lipid envelopes (oil encapsulations) which includes the covid-19 virus and mutations. N designates “no” protection against oil-particulates. So the best protection comes from a P95, P99, or P100s, as P designates specified protection against oil particulates.

      • The N95 respirators are worn for multiple purposes. There are some differences between N95s, but they are ALL designed to prevent intake of at least 95% of particles sized at .3 Microns. If your respirator is a genuine N95, it will have this capability. This assumes you have a proper fit and seal to your face and there is no structural damage to the mask. Some will cover an exhaust valve with an additional medical germ mask to protect others. I have some older “never used” N95s where I discovered the straps had deteriorated, so they were not safe to use in potentially contaminated areas.

        Reply
  9. The problem when you compare data sheets and not real world scenarios.

    “A new report found signs that popular KN95 masks are not as effective as N95 masks.

    Researchers at ECRI found that up to 70 percent KN95 masks imported from China don’t meet U.S. standards for effectiveness as with N95 masks. The group issued a hazard warning in September

    Both products are said to filter 95 percent of aerosol particulates. KN95 respirators differ from N95 respirators because they meet the Chinese standard but are not regulated by U.S. agencies.

    In the United States, the National Institute for Occupational Safety and Health (NIOSHTrusted Source) regulates masks.

    “There’s a potential misunderstanding in the public about the two masks,” Dr. Krutika Kuppalli, an infectious disease professor at Stanford University, told Healthline.”

    Source:

    https://www.healthline.com/health-news/report-finds-kn95-masks-not-as-effective-as-n95-masks

    Reply
  10. Ah yes the fit test, if you go beyond this article you will find that in many jurisdictions there is a requirement to be fit tested. The N95 is considered respiratory protection therefor it must be proven. As for protection against viruses 3M says it won’t protect against so I will go with that

    Reply
  11. Hello Team,

    I am looking for a reusable mask so that it is a one time investment sort of. I’ve come to know that masks with valves must be avoid for COVID protection. Hence please suggest a good mask without a valve with ultimate protection and reusability. This post here mentions so many types of masks N95, P95, R95, FFP blah blah. Really confused which one to seek. https://www.airswacch.com/p95-vs-n95-r95-p99-n99-r99-p100-n100-respirator-masks/

    Many thanks in advance!

    Reply
      • There is a must better explanation than that, NO it won’t. Smoke requires a full face respirator with special cartridges which the supplier should be able to steer you in the right direction on. Unless you are talking about an escape respirator which is a one time use divide that will protect from acid gas.

        Reply
      • Masks treated with activated carbon are only used in a nuisance level condition and cannot be used in levels that exceed the PEL (permissible exposure level)

        Reply
  12. You mentioned that an N95 it’s not required to have an RPT???? In US ??? We do require a rFt in order to use one and it works as it recommended by the manufacturer

    Reply
  13. This is such a refreshing site to visit and keep up to date with the science and facts behind and of the masks. You re doing a great job. Thank you so much for being a voice of reason and factual testing and information

    Reply
  14. I just purchased some KN95s (advertised as Medical Grade) from a UK Medical Supply Company with the hope of receiving more durable respirators. Upon arrival, the box stated “Conforms to the national KN95 standard, GB2626-2006, “non-medical” AND “Prevents dust, Prevents mist haze, Prevents saliva.” Are these later qualities common to all Non-medical KN95s? It is my understanding the designation of KN95 reflects a degree of filtering capability ( equal to, or greater, than 95% of particles at .3 microns), and that individual production sites may vary on the types of materials or number of filter layers used in the construction of their respirators. So I wondered if “Prevents dust, Prevents mist haze, Prevents saliva” might signify more durable materials that might not be found in some other KN95s? Any thoughts?

    Reply
  15. As an immune supressed transplant patient, I find it very important to have high-quality masks on hand at all times. There is no doubt that the environment is laden with bacteria and viruses around us and it should be advisable for immune suppressed organ transplant patients to wear a mask when in large crowds, on airline flights and on public transit, especially during cold and flu season. I hope they become more affordable or covered by insurance sometime in the very near future.

    Reply
  16. Hi and thanks for the info. I am 76 and have COPD. I currently use a KN95 I purchased at a Staples store. I didn’t know there were 2 different 95 masks. Later I read that the number ’95’ is from the patent date of the material and process.
    My problem with mask(s) is that they make it more difficult for me to breathe and can lead to a shortness-of-breath issue. Since I am overly vulnerable to the worst effects of the virus, I need to know if there is a compromise out there. A mask that sufficiently restricts the flow of particles while at the same time is easiest to breathe with. Any thoughts would be appreciated

    Reply
    • Hi James, Liz here. I’m so sorry to hear that you have COPD, it must be hard to live through this special period of time. The are actually more standards for the 95 level (or similar level) masks, here is the link if you want to know more: https://smartairfilters.com/en/blog/comparison-mask-standards-rating-effectiveness/
      You could see from the table that all of the 95 level masks are sharing similar standard. We do not recommend people with pre-existing cardiopulmonary conditions to wear this type of mask without talking to their physicians first. I would suggest you to talk to your doctor so he or she can help to pick the best protection option for you. Stay safe!

      Reply
    • James, have you tried a KN95 or N95 with a 1-way exhalation valve? I could provide a link if permissible on this site.

      Reply
      • Any mask with and exhalation valve WILL NOT PROTECT OTHERS from what the wearer exhales.

        DO NOT USE masks with valves during the pandemic. The main purpose of wearing a mask right now is to reduce the transmission from an infected person to other people.

        Masks with exhalation valves are actually made for construction work to protect the wearer from dust and other toxic particles.

        The exhalation valve makes the mask easier to wear in that it allows moisture buildup in the mask to be exhaled into the atmosphere. They are not to be used when protection for others is necessary.

        Let me repeat – do not use a mask with an exhalation valve for the purpose of protecting other people from what you exhale!

        With an exhale valve, the mask may protect the wearer but it will do NOTHING to protect those around you.

        Reply
        • My mask has the exhalation valve..but Also a pocket for the 5 layer carbon filter which I use..it is cloth and fits my face really well without noticeable gaps.

    • Hi James, one possibility for you would be great breathing-wise but a little costly and bulky. I used to work in a hazardous powder area and we wore PAPR 1/2 mask units. It was a battery powered fan that attached to belt and sucked air in through filters and pushed a slight breeze into your face. The mask fit over mouth and nose only, and connected to pack by hose. There is one out there that has no hose, filter and pack are on backside of neck but in this covid age that is right at breathing level. My preference would be filter belt high. Maybe manufacturers will start making with clear mask and hose. Good luck.

      Reply
    • Hi Mokhles, Liz here. We do have an official list of KN95 masks that fulfill the standard and can be export. The information is available online too on the official website. Email us I’ll send you the excel sheets I worked on, hope that helps!

      Reply
  17. Hello, I’m a nurse for a large agency that shelters and houses clients at high risk for COVID-19. We have a large shipment of KN95 masks that we’d like to use to protect our staff. The packaging on the masks have both standards, GB2626-2006 (dusk mask quality) and YY046-2011. (surgical masks). These seems contradictory! Hope you can help.
    Thanks
    Mary

    Reply
    • Hi Mary, Liz here. Usually, the mask manufacturer wouldn’t get two standard test for one model. If you are not sure about the mask you got, you can send a picture via our contact form so our engineer can help to take a look. Also, there is no reason for them to use a surgical mask standard to label an KN95 mask, did you open the box to see the actual product? Maybe there are two types of masks in the package.

      Reply
  18. It wasn’t until the pandemic that it was “ok” to reuse an N95. The standards have been lowered because of availability. As an RN of 27 years I find this despicable.

    Reply
    • Hi Krista, Liz here. Yeah I totally feel you, especially as a healthcare professional, you guys need more protection and the hospitals and clinics should have a special protocol to guarantee that. It is also a special period of time when even hospitals and clinics are short of mask supplies. There is something might be comforting, that we found simply by leaving you mask out and let it dry for a couple day can be a good way to disinfect them. Here is the article: https://smartairfilters.com/en/blog/disinfect-clean-n95-mask-virus-coronavirus/ I hope the facility you are working at don’t have to face this mask shortage for long. Stay safe and greetings from all of us in SA Beijing office.

      Reply
  19. I just bought a KN95 mask. I was shocked to find that it is full of small holes about 1/2 millimeter in diameter. In addition, the figures KN95 are punched out of the material of the mask letting light shine through. I don’t understand how a KN95 can be compared favorably to an N95 that is not full of holes.

    Reply
    • Hi Franklin, both the N95 and KN95 have the filtration efficiency tested with the whole mask. The holes you see on your mask is just craft differences. Some of the N95 masks also have the little “holes” on them.

      Reply
    • What worries me the most is how light the KN95s are, secondly, the packages of the individual masks are written ” not for medical use” . Honestly I feel better assurance wearing the N95, especially working at a clinic.

      Reply
  20. Avoid the Chinese made K N95 masks . The FDA just banned many of them for use in healthcare environments because they failed laboratory testing here in the United States. and several filtered 25% or less of what they should have

    Reply
    • Hi Patrick, Liz here. Not all KN95 masks are with bad quality. The standard is as listed in this article and yes, some of the manufactures making masks doesn’t fulfill the standard and claim that they are KN95, but if you are sourcing from a reliable manufacturer or an authorized domestic dealer the mask’s quality should be guaranteed. You can also ask for the certificate and test report when making a mask purchase.

      Reply
  21. Hi there everyone I wish for you and your family live in safety and prosperity.
    My Question is related to their use.
    1) What is their maximum life? I mean for how long can we use KN95 and N95 masks?
    2) Can wash them?
    3) Can we use them after washing them and for how long they are safe if we follow this same way to minimize the cost or expenses?
    As I work in retail sector and I get involved many of public dealings but I want my customers, my family, myself and everyone out there to be very safe, but this question remains always on the top my mind please let me know about it.

    Reply
    • Hi Muhammad, Liz here. Since you work in retail sector, and may encounter many customers in a day, I would suggest to change your mask every time you take it off for lunch or a break just in case. The best way to disinfect your mask is to leave it out to dry for 3 days and washing them may decrease the filtration efficiency so I won’t recommend that. For all of your questions, you can search the knowledge base with key words to find the answers: https://smartairfilters.com/learn/

      Reply
    • Viruses live in moist areas, which is why you should never wash an n95 or kn95 mask I think hanging it on a clothesline for 3 days in the sun is a good way to disinfect it. Take care, and thank you for working with customers, and keeping them and your self safe,

      Reply
    • Hi Brenda. Song here. There are two types of N95 masks, one is a medical equipment certified, another is just a protective wear. The former is required by most hospitals and clinics for the material can stands for a high pressure for liquid split. For both N95 and KN95 non-medical masks, the water resistance ability is weaker. It can still protect droplets from sneezing or coughing. I suggest you to follow your local CDC and hospital protection protocol. Stay safe

      Reply
  22. Is it ok to use KN95 disposable masks (the non medical ones) in health care facilities? are they safe?

    Reply
    • Hi Wendy, Liz here. It depends on your role in the health care facilities. KN95 is a non-medical standard. The mask has a filtration performance the same as N95, as said in this article. There are two types of N95 masks, one is a medical equipment certified, another is just a protective wear. The former is required by most hospitals and clinics for the material can stands for a high pressure for liquid spilt (like when an artery is cut by accident). If you are a healthcare professional, follow your local CDC and hospital protection protocol. If you just go to the hospital for a visit, then personally, I’d say both KN95 or a normal N95 would do a good job.

      Reply
  23. What do you mean by the best way to clean the N95 mask is to dry it? Most people aren’t getting theirs wet. Do you mean lay in sun? Actual dryer? Just set in paper bag?

    Reply
    • Hi Sue, there are two type of N95 and KN95, one if for hospital setting, another is not. So for both N95 and KN95, the hospital medical mask standard has strong water resistance that can provide healthcare professionals in case there is a huge amount of fluid splash. For both N95 and KN95 non-medical masks, the water resistance ability is weaker. It can still protect droplets from sneezing or coughing, but the protection effect would not be as good.

      Reply
      • Many thanks for this, I am unsure which type we have, we have KN95 GB2626-2006 is this for a hospital setting

        Thank you again

        Reply
        • GB2626 is the standard for dust masks, and the medical standard is GB19083, so KN95 of GB2626 is not recommended for use in hospitals

        • Can u plz give me a picture of GB19083 KN95 (medical grade)
          In this page, i hv seen all r GB2626 KN95.

    • Hi Abhi, Liz here. If you use it as a daily wear protection method, it should be doing as well as a N95 mask, which is really a great job on protecting you from covid. But if you are a healthcare professional, you will need to follow the hospital or your local CDC’s protocol on choosing protection equipment. The general KN95 and N95 doesn’t have medical device certificate shouldn’t be used in high risk environment by healthcare professionals.

      Reply
  24. What happened to the link above to the YouTube video re: “WATCH: What’s the Difference Between N95 and KN95?”

    Reply
    • Hi Dave, Liz here. Thank you for pointing this out! Our engineer has fixed the issue. The video should be available now!

      Reply
  25. Masks with exhalation valves allow the wearer to exhale unfiltered air and particles into the environment. Therefor, masks with exhalation valves do not meet the face covering requirements of public health authorities. They are not allowed in the county I live in. Valved masks are for personal protection, not for the public health.

    Reply
    • Hi Ted, Liz here. You are right. Unless the person is sure that he or she is not infected, wearing a mask with valve can be irresponsible to people around because it is a single way protection.

      Reply
    • Hi Amie, Liz here. Cement dust (wet or dry) is also a particular pollutant with a diameter of 3.68 μm. So the KN95 mask should have the 95%+ filtration rate for large particles. According to the mask testing standard, it doesn’t require the mask to be resistant to oil. If you need your mask to be oil resistant, you can check P95 or KP95 masks.

      Reply
  26. Wonderful article thank you for the details. Now, can you tell me how to check for fraudulent mask? What markings should I look for? I have to travel in August and want to be certain the mask I have is quality. There are peddlers selling the KN95 which now I know is fine for my needs. However, how do I make sure it’s not a knock off? Chinese are so good at selling imitations.

    Reply
  27. Paddy, since the Corona virus is of 0.1 micron size, can you post a chart explaining how much % of “this sized particles” do N95, Surgical and Cloth masks block? I want to see data for 0.12 micron , not data for 30 micron.

    Reply
  28. What I don’t understand is why a certified “test fit” is required for a disposable mask. That would mean that you would need to do a certified “test fit” every time you grab a new mask from the box. Not every mask in the box is the same shape (Engineering and Manufacturing tolerance) and pinching the nose is required to bend the metal to fit around your nose, which can not be replicated exactly every time.

    I have a full face respirator made of plastic and rubber that is molded to my face that required a certified “test fit” which makes sense because all I need to do is change the cartridge.

    Reply
  29. Hello,

    I just discovered your site and have been reading through it. In your discussion of various methods to sterilize a face mask so as to make it reusable, you don’t make mention of a method which I use which is so simple, and obvious that I was surprised that you hadn’t mentioned it. I simply heat my oven to about 160 degrees (Fahrenheit), then turn off the heat and put my masks on the tray inside (or rather, on the grill so that all parts of the mask are equally heated). After about 15 minutes I check how they are doing and usually I’ll take them out, reheat the oven to 160 degrees,, and repeat the process. The heat will eventually ruin the stretchy straps, but they seem to survive several reuses and sterilizations. The chief advantage of heating in an oven over washing or an alcohol bath is fluids damage the filter elements. As I understand it, one or more layers of the mask material possesses electrostatic properties that attract and hold onto minute particles, and washing or the use of fluids impairs the electrostatic properties of these materials. Now what I don’t know – and of course this is the crux of the whole thing – is how vulnerable this Coronavirus is to temperatures, especially temperatures greatly exceeding normal temperatures in the natural world. I am simply assuming that no virus would able to withstand greatly increased temperatures to those it would normally encounter. Do you know at what temperature Covid-19 is reliably destroyed?

    Best regards,
    Dorian Schneidman, Los Angeles

    Reply
  30. OSHA classifies an N-95 as a respirator. As such, employers are required to fit test and train their employees when wearing an N-95. If an employer provides an N-95 to the employee to wear voluntarily, the employee must sign a waiver form to allow the wearing of the particulate respirator. The waiver form is Appendix D in 29 CFR 1910.134. Employees still have to be trained in the use of this type. BTW: NIOSH sets the standard, OSHA enforces the standards onto employers.

    Reply
  31. I think a REAL KN95 mask will be equivalent to an N95 or FFP2 one. However, with even Chinese toy manufacturers now having switched to producing KN95 masks, the question is what quality you’ll be getting when buying one. I’ve read that the machines required to create the electrostatic fibre structure of the middle layer are highly specific, which explains the difficulty in ramping up production of N95 in the US. This combined with how easy it is to make a mask look genuine, means the market is flooded with masks that don’t meet the standards. That’s a concern. I’m an anesthesiologist and like to wear them during airway management of patients receiving elective surgery. Any way how I can spot the good from the bad here?

    Reply
  32. I have tried washing (by using toorhbrush & then pouring really hot water & let hang to dry)
    my 3M N95 several times & looks still good. Does it offer same protection? I then put a surgical mass on it. So, 2 mask. Coz I am not sure if the N95 offers same protection.

    Reply
  33. *PLEASE* put a big red “not true” lettering over the pictures/charts that are false. Instead of randomly mixing true and false images and buried somewhere in the text are small mentions of what’s true/false. Ugh. People on Facebook are sharing the “false” images as “directly found on SmartAirFilters.com”

    Reply
    • Great point Jill, we definitely don’t want to see the data being taken out of context. We’ve updated the graphic in this article to state how it is misleading.

      Reply
  34. Thanks for satisfying my nerdy inquirer. Paid news (pharma-socialist-govt) don’t seem to cover non-suspense topics like this.
    Any info about bra masks? Dr Elena Bodnar won the LG Nobel in 2009 for designing bra-masks. Demo:
    “As mask supplies dwindle, Japanese bra maker offers support where it’s most needed. A face mask made by Atsumi Fashion Co., a sewing company based in Toyama Prefecture, uses repurposed women’s underwear. Mar 21, 2020. Bras & masks are made of similar materials.
    The padded cups work better than unpadded. I use the lighter removable foam paddings as inserts for my cloth masks. Even shoulder pads inside the dust or green masks are more comfy than the masks. Stick with A, B, C cups. D and larger cups might as well cover my whole head!
    I insert cotton makeup removal pads (circles & squares), bladder pads, nursing pads, or a single Kotex pad (looks funky and has so many layers, and so easy to breathe. They all work well, per muscle testing on myself. Even a bandana works really well- folded, over the ears, tied in back (8 layers snug under the nez, or add a makeup pad into the folds). Make an additional roll inside, under the eyes, for fit. Put on glasses to test. No fogging! means no leaks!

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  35. Great write up. I have a question about the China GB standards. You mention GB 2626-2006 (plus the similar GB 2626-2016) which is for KN95 masks. My understanding is that these do not require medical-grade testing for liquids and microbial index limits. However, the specification for China GB 19083-2010 is for medical protective masks.

    If a mask from China meets the GB 19083-2010 standard it will also pass the less stringent KN95 standard of GB 2626-2006.

    Are you familiar with these standards? My question is if people purchase KN95 masks thinking they are medical grade they may be less effective than hoped.

    Reply
    • Troy, I just purchased some KN95s (advertised as Medical Grade) from a UK Medical Supply Company with the hope of receiving more durable respirators. Upon arrival, the box stated “Conforms to the national KN95 standard, GB2626-2006, “non-medical” AND “Prevents dust, Prevents mist haze, Prevents saliva.” Are these later qualities common to all Non-medical KN95s? It is my understanding the designation of KN95 reflects a degree of filtering capability ( equal to, or greater, than 95% of particles at .3 microns), and that individual production sites may vary on the types of materials or number of filter layers used in the construction of their respirators. So I wondered if “Prevents dust, Prevents mist haze, Prevents saliva” might signify more durable materials than might be found in some other KN95s? Any thoughts?

      Reply
  36. You must have a fit test for the N95. The KN95 is not regulated by NIOSH or OSHA and doesn’t require fit testing although it is recommended. Without a fit test, you might as well wear a Level 3 mask with a 98% filtration.

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  37. I am high risk. And I know that hospitals get masks first. I want to buy the kn95 3 pack. Will it ship to my p.o. box, and how long will it take? Ty

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  38. Hi, i have a question. Is there a difference if the respirator uses the elastic loops over the ear or if it is worn over the neck, as the kn95??

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    • hi Marco, strip designs doesn’t affect the mask efficiency. So you can pick one with the loop that helps to fit the mask on your face the best.

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      • That’s not true. NIOSH will not approve a respirator as N95 if it has ear loops; it must have bands for proper seal.

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      • Yes, there is a fit/protective difference. Air leakage is expected among ear loop masks as opposed to headbands. Ear loops do not provide the same fit or pressure over the wearer’s face.

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    • there is a huge difference. remember that the effectiveness of a respirator depends on the seal. loops that go around your ears will never be ass tight as ones going around your head and neck and note that many N95 respirators have adjustable strap

      Reply
  39. I think you have this wrong. I have always had to get a “fit test” with N-95 masks for healthcare usage. Many years and many different companies have required this.

    Reply
    • We’ve updated our article to add more clarity on this matter, Cathy. The N95 (NIOSH) standard does not require a fit test, but many hospitals and companies do. We’ve added this to the article.

      Reply
      • It is actually a requirement for companies to give individual yearly fit tests for any close fitting respirator. So in actuality, our regulations on fit test are stricter because we are required to have an in place written respiratory protection program with a qualified administrator and each person that is required to use a close fitting mask (N95) is required to have the fit test yearly, and if there is a noticeable change to the facial structure of the individual (weight loss or gain, or accident, tooth loss)

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        • Hi James, Liz here. If you mean the mask instruction manual for users mentioning a fit test, that make sense! The N95 standard doesn’t require the manufacture to pass a fit test when labeling your mask as a N95 mask. However, the filtration efficiency in individual largely affected by the fitness. Here is an article on how we suggest anyone who doesn’t have access to a professional fit test equipment to conduct your own test: https://smartairfilters.com/en/blog/poor-mans-fit-test/

      • I do not recall a certified quantitative or qualitative fit testing protocal by NIOSH or OSHA for MASKS only for negative type respirators. It may also be noted that having a beard or small amount of facial hair lessens the effectiveness of a mask or respirator by 30% to 95% depending on the growth of facial hair interference. There is no respirator that can be accurately fit tested with facial hair and since there is no certified method to fit test a Mask of any kind its a mot point. I believe in NIOSHs fit testing protocol they state no facial hair and I believe that OSHA states facial hair is not allowed in their respirator program standard, when wearing a respirator or Mask if the work environment requires it would be acceptable. Look forward to a response to my statement via a IH.

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    • Cathy I thought same thing but if you reread, The requirement is per company to make that decision They are saying it is not a recommended requirement under our Federal Code.

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  40. This is not true that N95 masks do not have to be fit tested. N95 masks do require fit testing, otherwise you might think you are protected, but if the mask does not fit correctly over the nose, there will be significant air leakage around the edges of the mask. Health care workers in the US are fit tested annually to make sure there haven’t been changes due to weight changes. In my hospital if you do not go in for your fit test, you get locked out of the electronic medical record until you complete the fit testing. On my disaster team we had one team member unable to successfully fit test any of the available N95 mask sizes, and had to be fitted to a P 100 mask, due to configuration of her face. Fit test kits are available, which have a hood through which a nontoxic chemical is sprayed, that can be tasted if the mask does not block it out.

    Reply
      • Hi, This is not right at all. NIOSH requires the N95’s and other Respirators to be fit tested per a couple of standards: RCT-APR-0067-508 and TEB-APR-STP-0005-05a-06-508, you can find them on CDC website, it is made public. The caveat that NIOSH makes, is that “They will decide” if the design of such mask being approved is of a “novel design” or not. If the design of for the fit was previously tested, they will waive these two tests.

        Reply
    • The blogger states that china regulators require manufacturers to run fit test before marketing for sale, whereas US does not require this fit test before sale to the public or health organ.

      Reply
    • As a hygienist in a dental practice, we’re not back to work yet during pandemic, they bought KN95 masks for us to eventually use. No regard to size. Doesn’t seem to reassuring. Your thoughts on that?

      Reply

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