If the heat made it difficult to wear a mask, the arrival of the rainy season marks the start of another situation: that of a wet mask. But is the mask still effective when wet?
A wet mask is an ineffective mask
The mask, which has become compulsory in several French cities, loses its effectiveness when it is wet. To be effective, the mask must be perfectly dry. If it gets wet, it must be changed. Indeed, the water drops more easily permeate the mask and allow the droplets to pass. The French Standardization Association (Afnor) explains that “ The degree of protection of the masks is measured by the static electricity of the fibers of the fabric which stops the droplets of the postilions. However, if the mask is wet, this static electricity disappears and the droplets pass more easily “. During the heatwave of this month of August, it was recommended to change your mask if it was wet (perspiration, water) because its ” effectiveness is no longer guaranteed », A case which also applies here with the rain. Afnor also recalls that “ the mask can be worn for a maximum of 4 hours. Why ? Because that’s the life of the filter. Beyond that, it will no longer be filtering “.
Characteristics and proper use of the mask
The Association also recalls that the material of the mask must be ” more breathable possible “. It must also meet the characteristics of permeability, breathability and filtering of at least 70% of particles of 3 micrometers. When the mask is wet, this is no longer the case. To avoid this situation, it is recommended to take an umbrella to preserve the mask as much as possible. Regarding the fabric mask, Afnor indicates that it “ should be washed whenever it is soiled, wet or improperly positioned on the face. It should not be put in the waiting position on the forehead or under the chin during and after use “.
