Your browser is not supported for the Live Clock Timer, please visit the Support Center for support.

WHO recommendations on wearing masks to prevent coronavirus

What types of masks are used against the spread of COVID-19?
Medical masks (also known as surgical masks): these are made from a minimum of three layers of synthetic nonwoven materials, and configured to have filtration layers sandwiched in the middle. These masks are available in different thicknesses, have various levels of fluid-resistance and two levels of filtration. These medical masks reduce the respiratory droplets from the wearer to others and to the environment. They also prevent transmission of the virus from others to the wearer.

What is WHO recommending to countries that are considering the use of masks for the general public?

For countries that are considering the use of masks, WHO advises decision-makers to apply a risk-based approach to decide where, when and what type of masks should be used.  WHO advises decision makers to consider the following:

Purpose of mask use: if the intention is preventing the wearer transmitting infection to others (source control) or to offer protection to the wearer against infection (prevention).

Risk of exposure to COVID-19 to the population or individual:

  • Population level exposure measured by the amount of COVID-19 circulation in the community: that is, if there is known or suspected community transmission occurring.
  • Individual level exposure depending on a person’s occupation: e.g., individuals working in close contact with the public (e.g., community health worker, cashier).

Vulnerability of the mask wearer/population: for example, if supplies are adequate, medical masks should be used by people with pre-existing medical conditions, such as chronic respiratory disease, cardiovascular disease, cancer, immunocompromised patients or diabetes mellitus of any age, or people aged 60 and over.

Setting in which the population lives: settings with high population density (e.g. refugee camps, those living in cramped conditions) and settings where individuals are unable to keep a safe distance (e.g. crowded buses or other transport).

Feasibility: availability and costs of masks, access to clean water to wash non-medical masks, and ability of mask wearers to tolerate adverse effects of wearing a mask.

Type of mask: medical mask versus non-medical mask. Medical masks should be prioritized for health workers, symptomatic people and their caregivers.

In addition to these factors, potential advantages of the use of masks by the general population in the community setting include reducing potential exposure risk from an infected person during the ‘pre-symptomatic’ period or if an infected person is asymptomatic (that is when they may not have symptoms).

There are potential risks and disadvantages that should be taken into account in any decision-making process on the use of masks:

  • Non-medical or fabric masks could increase potential for COVID-19 to infect a person if the mask is contaminated by dirty hands and touched often, or kept on other parts of the face or head and then placed back over the mouth and nose
  • Depending on the type of mask used, could cause difficulty in breathing
  • They can lead to facial skin breakdown
  • They can lead to difficulty with communicating clearly
  • They can be uncomfortable to wear
  • It is possible that mask use, with unclear benefits, could create a false sense of security in the wearer, leading to diminished practice of recognized beneficial preventive measures such as physical distancing and hand hygiene.
  • What types of masks are used against the spread of COVID-19?

    Medical masks (also known as surgical masks): these are made from a minimum of three layers of synthetic nonwoven materials, and configured to have filtration layers sandwiched in the middle. These masks are available in different thicknesses, have various levels of fluid-resistance and two levels of filtration. These medical masks reduce the respiratory droplets from the wearer to others and to the environment. They also prevent transmission of the virus from others to the wearer.

    Hands should be cleaned with alcohol-based hand rub or soap and water before putting on a clean mask and after removing the mask. These masks should be worn tightly on the face. The wearer should avoid touching the mask while it is on the face and the mask should be immediately discarded if it becomes moist. Importantly, wearing a mask must be combined with other preventive measures including performing frequent hand hygiene and physical distancing of at least 1 metre.

    When and how to use masks

    Respirators (also known as filtering facepiece respirators – FFP) and available at different performance levels such as FFP2, FFP3, N95, N99): these are specifically designed for healthcare workers who provide care to COVID-19 patients in settings and areas where aerosol generating procedures are undertaken. Healthcare workers should be fit tested before using a respirator to ensure that they are wearing the correct size.

    Non-medical masks (also known as fabric masks, home-made masks, DIY masks) can act as a barrier to prevent the spread of the virus from the wearer to others.

    They can be purchased commercially or handmade, and are generally not standardized like medical masks. There are numerous types of fabric masks, they should cover the nose, mouth, and chin and be secured with elastic loops or ties, include multiple layers, be washable and reusable.

    Remember, the use of a fabric mask alone is not sufficient to provide an adequate level of protection. Maintain a minimum physical distance of at least 1 metre from others, frequently clean your hands and continue to avoid touching your face and the mask.

    WHO will be referring to non-medical masks as fabric masks.

More News from City Talk