Since the advent of Coronavirus disease, the whole world has gone crazy after two things i.e Hand Sanitizers and Face Masks. The fear of the disease has gripped everyone so much that people who didn’t have any exposure to the carrier, are wearing face masks even at home. They are using hand sanitizers like anything. The impact of this panic usage has led to a situation where our frontline workers consisting of infection prevention and control (IPC) professionals, health care managers, health care workers (HCWs), and community health workers are not getting the requisite PPE kits and sanitizers.

We have already tried to clear the myths about the usage of hand sanitizers in our previous two publications “Hand Sanitizer and COVID-19 – Understanding the Misunderstood” and “Hand Sanitizer and COVID-19 – Understanding the Misunderstood – Part 2”.

In this article we shall be sharing the information on various types of masks, their efficiency, effectiveness, usage, experts view, regulatory recommendations, handling of used masks and much more.

What are face masks? Face masks are a part of Personal Protective Equipment (PPE) that should be worn on face to cover nose and mouth as they are the possible organs of inhaling any contaminant.

What are various types of face masks? Currently the market is flooded with masks of various types, specifications and shapes etc. However, majorly there are following types of masks:

  1. Surgical masks (3 ply): A surgical mask is made from paper or other non-woven material and should be discarded after each use. Usually the surgical masks are three-ply (three layers). This three-ply material is made up from a melt-blown material placed between non-woven fabric. The melt-blown material acts as the filter that stops microbes from entering or exiting the mask. Most surgical masks feature pleats or folds. 
  1. Respirator masks – N series (N95, N99, N100 and Surgical N95): A respiratory mask is made from electrostatic non-woven polypropylene fiber. They are secured tightly to the face, with 2 head straps and a nose adjustable clip over the nose to allow for a more custom fit. Respirators are usually tested and certified by the U.S. National Institute of Occupational Safety and Health (NIOSH).

In respiratory masks, N stands for “non-oil”, it means it can protect against only non-oil particulates. 95 stands for 95% efficiency against the particles of size 0.3 micron. Similarly, 99 stands for 99% efficiency and 100 stands for 99.97%efficiency.

Surgical N95 respirators are for those healthcare workers who requires respiratory protection while performing surgery or other tasks that may expose them to high pressure streams of bodily fluid or conducting work in a sterile field.

  1. Respirator masks – FFP series (FFP1, FFP2, FFP3): These masks are similar to N series respirators masks but they follow Europe standards of classification which classifies masks into different grades based on how much protection they offer. They are classified as following:

 

FFP1: This mask has a filtration of at least 80% and the inside leakage is 22% maximum. This mask is mainly used as a dust mask.

FFP2: This mask has a filtration of at least 94% and the inside leakage is 8% maximum. This mask is similar to N95 masks w.r.t. filtration capability and is used by healthcare workers for protection against coronavirus in Europe.

FFP3: This mask has a filtration of at least 99% and the inside leakage is 2% maximum. This mask is similar to N99 masks w.r.t. filtration capability and is also used by healthcare workers for protection against coronavirus in Europe.

 

What are various designs of face masks? Apart from filtration capacities as mentioned above, face masks come with various designs also. Few of important design considerations are as mentioned below:

  1. Unvalved: These masks come with the filtration system built into the fabric. They are lightweight and hence are comfortable to wear.
  2. Valved: These masks come with in-built exhalation valve which allows air to be let out of the mask. The presence of an exhalation valve reduces exhalation resistance, which makes it easier to breathe. The valve makes the mask a little bulky but they are less sweaty and stuffy and hence are comfortable to wear.
  3. Folded: These masks are foldable and are easy to carry around. They offer a close fit to the face with the help of elastic straps; however, they do not offer a perfectly flush fit.
  4. Moulded: These masks are designed according to the shape of face and fit snuggly to nose, mouth and chin. This provides higher protection as chances of microorganisms or any particle entering is fairly less due to tight fitting.

 

What are the major difference between various face masks?

 

Parameter Surgical Mask N Series Mask FFP Series Mask
Fitting Loose fitting Tight fitting Tight fitting
Fit testing No Yes Yes
Leakage Yes Minimal leakage Minimal leakage
Grades Usually single grade 3 ply mask N95, N99, N100 and Surgical N95 FFP1, FFP2, FFP3
Filtration Does NOT provide the wearer with a reliable level of protection from inhaling smaller airborne particles and is not considered respiratory protection Filters out at least 95% of airborne particles including large and small particles Filters out at least 80% of airborne particles including large and small particles
Specifications Local regulatory bodies NIOSH European Standards
Intended use and purpose Fluid resistant and provides the wearer protection against large droplets, splashes, or sprays of bodily or other hazardous fluids. Protects the patient from the wearer’s respiratory emissions. Reduces wearer’s exposure to particles including small particle aerosols and large droplets (only non-oil aerosols). Reduces wearer’s exposure to particles including small particle aerosols and large droplets (only non-oil aerosols).

 

Which masks to be used?

For healthcare workers, WHO recommends to wear a medical mask (surgical mask) when entering a room where patients with suspected or confirmed COVID-19 are admitted. WHO recommends to use minimum of N95 (NIOSH standard) and FFP2 (EU standard) or equivalent for the health workers when performing or working in settings where aerosol-generating procedures, such as tracheal intubation, non-invasive ventilation, tracheotomy, cardiopulmonary resuscitation, manual ventilation before intubation, and bronchoscopy are performed.

For symptomatic people, WHO recommends to wear a medical mask (surgical mask) while going to medical care facilities or waiting in triage or other areas. Masks are not necessary when isolated in a single room, but they should cover their mouth and nose when coughing or sneezing with disposable paper tissues. Tissues must be disposed of appropriately, and hand hygiene should be performed immediately afterwards.

Is it necessary for common people to wear masks?

This is a fact that use of mask by healthy people helps to reduce potential exposure risk from infected person during the “pre-symptomatic” period. However, one should also understand the following potential risks associated with it:

  1. Self-contamination that can occur by touching and reusing contaminated mask
  2. False sense of security, leading to potentially less adherence to other preventive measures such as physical distancing and hand hygiene
  3. Diversion of mask supplies and consequent shortage of mask for health care workers
  4. Diversion of resources from effective public health measures, such as hand hygiene
  5. Depending on type of mask used, potential breathing difficulties

Also, as per WHO, current evidences do not suggest the wide use of masks by healthy people in community settings. Also, it carries uncertainties and associated critical risks as it creates false sense of security, with neglect of other essential measures, such as hand hygiene practices and physical distancing. This should be understood by everyone that, the use of a mask alone is insufficient to provide an adequate level of protection. If you are healthy, you only need to wear a mask if you are taking care of a person with COVID-19. Wear a mask if you are coughing or sneezing.

Having said that, it is highly recommended that the person shall adhere to the guidelines provided by national health authorities or local administration regarding usage of masks.

Are nonmedical masks equivalent to surgical masks?

The non-standardized masks made of other materials such as fabric or cotton are known as nonmedical masks. These masks have not yet been evaluated for their filtration efficiency and ability to control the contamination. Hence, there are no current evidences available to make a recommendation for or against their use in current scenario.

In case usage of non-medical mask becomes a necessity, factors such as number of layers of fabric, breathability, shape of mask, fit of mask etc, shall be considered for selection of nonmedical mask.

How to wear, remove and discard a mask?

  1. Before putting a mask, wash your hands thoroughly with soap and water. Use hand sanitizer post hand washing.
  2. Place the mask carefully, ensuring it covers the mouth and nose, and tie it securely to minimize any gaps between the face and the mask.
  3. Avoid touching the front of mask while wearing it.
  4. While removing the mask, do not touch the front of mask but untie it from behind. In case, you touched a used mask, wash your hands thoroughly with soap and water. Use hand sanitizer post hand washing.
  5. Damp masks shall be removed immediately and fresh masks shall be used.
  6. Single use masks shall not be reused.
  7. Masks shall be discarded in closed bins.

Reference: Advice on the use of masks in the context of COVID-19 – WHO Interim Guidance