UniScienza&Ricerca: the UniSR blog

Protective masks: what differences?

Written by UniSR Communication Team | Oct 24, 2020 11:04:00 AM

SARS-CoV-2 is a virus transmitted by respiratory secretions (cough, sneezing, saliva droplets…). To avoid contagion, some rules are essential, such as maintaining a safety distance of at least 1 meter (better 2), avoiding crowded places, washing our hands often with soap and water or alcohol-based gel, avoid touching our eyes, nose and mouth with our hands.

For some time, the World Health Organization has specified the best practices for wearing masks. There are many types available: surgical, FFP2, FFP3, with or without exhalation valve… but what are the differences among them? Here is a small informative and non-exhaustive summary, to illustrate the diversity of masks available to date (remembering that masks alone are not enough to protect us from contagion, and always recommending to follow the instructions of the competent authorities).

Three categories of masks

Protective masks can be divided into three categories:

Surgical masks

As the name suggests, they are used by surgeons to maintain sterility in the operative field. They are made of non-woven fabric and do not adhere to the contours of the face, which is why the protection for the wearer is very limited; instead, by covering the nose and mouth, they serve to prevent the escape of respiratory secretions, droplets and potentially infectious particles to the external environment. To be safe, they must be produced in compliance with the technical standards (downloadable for free from the site https://www.uni.com).

High protection masks (FFP)

The high protection masks are the so-called "FFP" (the acronym stands for "filtering facepiece particles"). These devices protect both the wearer and others, and are optimal for protecting healthcare professionals directly involved in caring for a patient who is certainly or likely to be infected with SARS-CoV-2.

They are divided into the three protection classes FFP1, FFP2 and FFP3 according to their filtering efficiency. FFP1 masks filter at least 80% of the particles found in the air down to a size of 0.6 μm; a single particle of SARS-CoV-2 is about 5 times smaller, so they are not suitable for protection from airborne pathogens. FFP2 masks are suitable, they filter at least 94% of the particles found in the air down to a size of 0.6 μm; FFP3 masks offer the highest possible protection, with a filtering capacity of at least 99% from particles up to 0.6 μm in size.

FFP masks can also be equipped with exhalation valves, which however have no effect on the filtering capacity of the device, but allow for better breathing when the mask is worn for a long time. The exhalation valve allows hot air to escape from the device, reducing the humidity that forms inside it, avoiding the formation of condensation. This system prevents the glasses from fogging and facilitates breathing, but be careful: in this way, even viral particles can escape! As such, valve FFPs protect the wearer, but not others.

Non-sanitary masks

Masks not certified for medical use, which can be made with any type of fabric that covers the nose and mouth. These are not considered medical or personal protective devices; they can be produced under the responsibility of the manufacturer, who must in any case guarantee their safety.

The FFP2 and FFP3 masks are reserved for healthcare personnel engaged in certain clinical activities while, in the COVID-19 epidemic contingency, surgical masks can be useful to everyone especially when it is not possible to respect the physical safety distance” adds Prof. Carlo Signorelli, Full Professor of Hygiene and Public Health and Director of the UniSR School of Specialization in Hygiene and Preventive Medicine.

In any case, those wearing a mask must still comply with the precautionary rules on social distancing and the others introduced to deal with the Covid-19 emergency.

 

Important information

As suggested by the WHO, when there is a need to wear a mask, some important precautions must be followed:

  1. when handling the mask before wearing it, be sure that your hands are clean, so as not to risk contaminating an object that we will wear on the nose and mouth;
  2. the mask must adhere well to your face and completely cover your nose and mouth;
  3. the surgical mask should be changed when wetting due to breathing and in any case after 3/4 hours; do not reuse disposable masks;
  4. avoid touching the mask while wearing it, as it could contaminate its external surface; use the rubber bands or fabric ribbons to arrange it on the face;
  5. when removing the mask, it must always be considered that its external part could be contaminated: if disposable, it must be thrown into a closed basket and washed hands immediately after this manipulation.