Here are the different types of mask: 

1/ Surgical mask

The surgical mask is a disposable mask, so it should only be worn under certain conditions, and absolutely not on a repeated daily basis.

It protects only the exhalation of droplets during sneezing, not the inhalation, since it is not designed to protect the wearer. Its effectiveness lasts only 2 hours, and is diminished by humidity from sweat, the atmosphere and rain.

You have to wash your hands before putting it on, change it as soon as it gets wet, take it off without touching it, never put it in your pocket, in short, the exact opposite of what 90% of people do. In short, it’s designed for hospitals and doctors, but not for the general public, and especially not in the street and not all the time, only occasionally (sick, sneezing, hospital).

2/ FPP masks

An FFP (filtering facepiece, literally ” pièce faciale filtrante “) protective mask. Standard EN 149 defines three classes of filtration efficiency for these masks, namely

FFP1: filtering dust during DIY
FFP2: construction
FFP3: industry, asbestos, silica
Unlike a surgical mask, which mainly prevents droplets emitted by the wearer from spreading outside, an FFP mask must fit snugly over the face. It therefore protects the wearer from inhaling infectious agents or micro-particles.

Attention : The valve-equipped model allows exhalation with less effort, but loses its function as a barrier between the wearer and others or the environment.

Unfortunately, the concentration of carbon dioxide in breathable air can be well above the maximum permissible concentration (Concentration can exceed 3 %4,5,6; Weighted average exposure value = 0.5% (8 hours) 1.4% (fifteen minutes). If workers use respirators for many hours, they may suffer headaches and become ill. They may develop dermatitis and acne.

No evidence of mask effectiveness

WHO points out that :

If misused by the general public, the mask poses more problems than it solves
The mask is effective only if the wearer washes his or her hands frequently, with soap and water or an alcohol-based cleansing gel.

Side effects of these masks

For the person: polypropylene, germs (streptococci, staphylococci, fungi, viruses), CO2, acne, dermatitis, additional tax if you have to change it every day… Additional tax on middle classes weakened by the economic crisis: average budget of €230 per month per family.  
Below, a superinfected eczema caused by wearing the mandatory mask. The risk of impetigo, serious complications for the heart (rheumatic fever) and septicaemia is not negligible.

For the environment: it’s not environmentally friendly at all, wasting masks, wipes, gels, raw materials (deforestation…), polluting soil, rivers and the sea.  Polypropylene, a plastic material that takes up to several centuries to degrade in the environment.

Masks have been found in 7 European rivers! 

Composition of these masks

polypropylene surgical masks

We observe intolerance reactions in people who wear masks for a long time.Dr Brigitte Milpied, dermatologist and venereologist at Bordeaux University Hospital, based on her own practice and feedback from colleagues. She is a specialist in skin allergies and a member of the Groupe d’étude et de recherche en dermato-allergologie (Gerda),

In a 2009 report, the French National Institute for Research and Safety (INRS), which works to prevent occupational hazards, warned that masks are “a frequent cause of irritant dermatitis”. The organization also noted that “a worsening of facial acne when masks are worn for long periods is often reported”.

Watch this video of a man in profile sneezing to see that a mask is only useful if you sneeze, but useless if you’re well.

A man sneezing without anything, in his fist, his palm (the best protection, but you have to wash your hands afterwards), in a surgical mask and FFP2

This video shows the benefits of this mask only if you sneeze. And even then, the mask lets through the sputum, which spreads at a distance of less than 1 meter, and is less effective than sneezing into your palms or into a more airtight handkerchief.

The protection provided during inhalation is real, but not quantified for a surgical mask : it is not designed to protect the wearer against inhalation of airborne bacteria or viral particles. This is why FFP masks offer better protection for this type of use.

For the mask to remain effective, it must not be too damp, or even wet, as this would clog the filter layer. This can happen after prolonged wear (cumulative exhalation humidity), after intense and/or repeated sneezing, if the mask is soaked with sweat (sports use), or outdoors in the rain.

Many surgical masks have two faces : one white, containing the filter (i.e. to be placed in direct contact with the source of contamination : the wearer’s mouth and nose), and the other colored, usually blue, not containing the filter (i.e. to be placed towards the outside)10,11. The ” three-fold mask ” is worn with the folds facing outwards.

It should be removed by grasping the ties at the back, without touching the front (or back) of the mask, then disposed of (single-use) in an appropriate closed bin before washing hands again. 

The WHO recommends that you wash your hands thoroughly before putting the mask on, that you do not touch the mask during use (or clean your hands immediately), and that you change the mask as soon as it becomes damp. The mask should never be worn on the forehead, neck or ear, or placed in the pocket, as this could contaminate the wearer if it is repositioned.

The WHO points out that :

If misused by the general public, the mask poses more problems than it solves, and in any case, barrier gestures remain indispensable ;
The mask is effective only if the wearer washes his hands frequently, with soap and water or with an alcohol-based cleansing gel11.

 In short, masks are for professionals.

but absolutely not for the healthy general public.

Dr Pascal Trotta (corrected article and summary)