Journal of Family Medicine and Primary Care

: 2020  |  Volume : 9  |  Issue : 12  |  Page : 5850--5852

Unmasking N95 for COVID-19 health-care workers in India

Mrinal Barua1, Subodh Kumar2, Vivek Mishra3, Aroop Mohanty4, Hari S Joshi5,  
1 Department of Anatomy, AIIMS, Rishikesh, Uttarakhand, India
2 Department of Pulmonary Medicine, AIIMS, Gorakhpur, Uttar Pradesh, India
3 Department of Anatomy, AIIMS, Gorakhpur, Uttar Pradesh, India
4 Department of Microbiology, AIIMS, Gorakhpur, Uttar Pradesh, India
5 Community Medicine, AIIMS, Gorakhpur, Uttar Pradesh, India

Correspondence Address:
Dr. Mrinal Barua
Department of Anatomy, AIIMS, Rishikesh - 249 203, Uttarakhand


A general term N95 Mask has been widely used by all including the health care personnel. It has been use incorrectly by all and it should be replaced with the term filtering facepiece respirator. There are two types of respirators being used in the world. One is the industrial type whereas the other one is the medical surgical one. The medical surgical masks are an intermediate product between the industrial and the triple layer medical mask. Many other equivalent products like KN95 masks are also available in the market. There is an urgent need of certification because this is the only way quality face masks can be provided to the public in these difficult times of COVID-19. This is essential because of the entry of many counterfeit and uncertified respirators have entered the market.

How to cite this article:
Barua M, Kumar S, Mishra V, Mohanty A, Joshi HS. Unmasking N95 for COVID-19 health-care workers in India.J Family Med Prim Care 2020;9:5850-5852

How to cite this URL:
Barua M, Kumar S, Mishra V, Mohanty A, Joshi HS. Unmasking N95 for COVID-19 health-care workers in India. J Family Med Prim Care [serial online] 2020 [cited 2021 Jan 17 ];9:5850-5852
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Full Text

On March 19, 2020, the World Health Organization released the “Rational use of personal protective equipment (PPE) for coronavirus disease (COVID-19)” document[1] summarizing WHO's recommendations for the rational use of personal protective equipment (PPE) in health care and community settings, as well as during the handling of cargo. In line with the same recommendations, the Directorate General of Health Services (Ministry of Health and Family Welfare, Government of India) released the “Novel Coronavirus Disease 2019 (COVID-19): Guidelines on the rational use of Personal Protective Equipment” guidelines document[2] for health-care workers and others working in points of entries (POEs), quarantine centers, hospital, laboratory and primary health care/community settings. The document also lists all PPE including the ambiguous term “N95 respirator masks”.

The guideline document issued by the Government of India has incorrectly used the term N95 respirator mask for what should be known as Filtering Facepiece Respirator (FFR). This is a problem because N95 is a type of “Particulate” Filtering Facepiece Respirator (not resistant to oil). Here it is pertinent to make a distinction between an industrial (standard) N95 respirator and a Surgical (medical) N95s respirator that could be used by health-care professionals while delivering medical care.[3] A surgical N95s respirator is a single-use device that is also tested for its ability to resist penetration by high-pressure streams of liquid, for instance, a splash of blood, filtration efficiency, and bacterial filtration efficiency.[4] In the United States of America, where the term N95 has originated, an NIOSH (National Institute of Occupational Safety and Health) approved standard N95 respirator is approved by FDA as Surgical (medical) N95s respirator for health-care use only after it has cleared tests for resistance of medical face masks to penetration by synthetic blood. So in a way, Surgical N95 masks are an intermediate product between standard (industrial) N95 respirators and triple-layer medical masks. The Government of India has overcome this issue of fluid resistance by including an ASTM F1862, ISO 22609, or equivalent standard for FFRs.[2] Although this appears to be mandatory but considering the FFR shortage situation, health-care workers who are not likely to suffer splashes of blood or fluid may wear the standard NIOSH certified N95 respirator. All particulate FFRs used in health care without certification for fluid resistance (and only for particles) should carry with it a warning, at least to use face shields when there is a likelihood of a blood/fluid splash. FFRs with exhalation ports should not be used in situations where a sterile field must be maintained because it allows unfiltered exhaled air to escape.[4]

N95 respirator is just one type of particulate FFR. There are many other equivalents, for example, FFP2/P2 rated respirators (Filtering facepiece), KN95, etc., In addition to NIOSH certified N95 respirators, the Government of India has also prescribed an FFP2 mask with EN149:2001 standards (Quality compliant with standards for “medical N95 respirator”: a. NIOSH N95, EN 149FFP2, or equivalent). In the guideline document, the difference between a surgical (medical) N95s respirator and standard N95 respirator is not categorically stated. Also, whether to use the Bureau of Indian Standards BIS 9473:2002 FFP class 2 S/SL for respiratory masks[5] is surprisingly not included, although it is an equivalent FFR.

Certification is an important consideration here because this is the only way by which health-care organizations can assure the quality of a respirator/mask. N95 types of particulate respirators are certified by NIOSH and also by FDA if ASTM (American Society of Testing and Material) certified. All NIOSH certified FFRs bear an NIOSH testing and certification approval number on individual respirators or packaging, for example, TC-84A-XXXX. This approval number may be verified on the NIOSH website. Besides, a comprehensive list of FDA approved surgical N95 respirator models may be accessed at

EN 149:2001 FFP2 is an equivalent European standard for FFRs, and individual certificates/packaging/respirators may be checked for verification or on the rapid alert system for dangerous non-food products (

Bureau of Indian Standards (BIS) certified masks will bear the standard mark“ISI” on all FFRs with CM/L number. A list of licensed vendors of BIS masks may be searched at for further verification. KN95 masks were recently approved by FDA, USA as a non-NIOSH certified NIOSH equivalent FFR. These FFRs will bear the Code of China standard number GB 2626-2019 issued on 31 December 2019. The other equivalent FFR types & certifications are P2 Australia New Zealand AS/NZA 1716:2012, Korea 1st class Korea KMOEL-2017-64 and DS Japan JMHLW-Notification 214, 2018. To allay fear and panic amongst workers, health-care organizations in India must include “equivalent” certifications in their COVID-19 policy documents. It is important to know that certifications are not valid after expiry of products.

As India faces massive shortage of FFRs amid this COVID-19 pandemic, many counterfeits and uncertified respirators are finding their way into the health-care system.[6] Counterfeits and uncertified respirators are two distinct entities. Counterfeits are a fraudulent imitation of a genuine product. They may be recognized by having a high index of suspicion, verifying manufacturers & trademarks from certifying agencies and purchasing from authorized retailers. Uncertified respirators present a different problem. Although manufacturers do test FFRs in their laboratories for quality, it is possible that certification may be delayed due to procedural reasons or bureaucracy. Though not quality assured, this automatically does not translate into the fact that FFRs are of a poor quality. In times of shortage, a supply of uncertified FFRs may present serious dilemmas for health-care professionals. A classic example are respirators with N95 labels but without any certification marks doing rounds in hospitals across India. Another example of possible counterfeit FFRs is when two or more certifications/standards are printed on the same masks, for example, both NIOSH and EN149. A list of authorized dealers with their nodal officers appointed by the government of India may be accessed here

There are speculations about the effectiveness of N95 FFRs over triple-layer medical masks. A randomized control trial[7] published in JAMA on 03 September 2019 has concluded that “among outpatient health-care personnel, N95 respirators vs. medical masks as worn by participants in this trial resulted in no significant difference in the incidence of laboratory-confirmed influenza”. Trials like this on the one hand though reduces fear amongst health-care workers, but on the other hand may serve to trivialize the extent of the problem if results are accepted at face value. Both medical masks and FFRs are barriers against droplets and bioaerosols but FFRs have an additional property of sealing the user's face around nose and mouth. In principle, medical masks are worn to prevent transmission of infection from health-care professionals to patients and FFRs are to prevent the occupational hazard of getting infected from patients. Although there is not enough evidence to support airborne transmission of COVID-19, “WHO continues to recommend airborne precautions for circumstances and settings in which aerosol-generating procedures and support treatment are performed, according to risk assessment.”[8]

FFRs are an important component of PPE and one should stick to certified respirators, both for particles (including bioaerosols) and fluid resistance. The decision to use laboratory-tested but uncertified FFRs in times of shortage/crisis is a difficult one but requires a judicious balancing of risks and benefits by health-care authorities. The use of triple-layer medical masks could be an acceptable option in times of shortage.[9],[10]

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Conflicts of interest

There are no conflicts of interest.


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