< Masks
How do you put on and take off your mask?
Text updated on 2020-05-03
Using a mask without contamination requires some practice. Follow the tutorial!
Using a mask without contamination requires some practice. Follow the tutorial!
The aim is to avoid contaminating oneself and others by handling the mask.
Step by step
- if you plan to wear your mask for several hours, drink water before putting it on. This will save you from having to take the mask off to drink.
- always wash your hands before putting on and taking off your mask
- if you have long hair, tie it up so that it doesn't get between the mask and your face.
- Cover your nose and mouth well, check that there is no air passing through the sides. If there is a metal bar, pinch it to adjust the top of the mask over the nose. When you blow, there should be no air in your eyes. If you wear glasses and your lenses fog up, it means that the mask is wrongly positioned. Take the time to adjust it so you don't have to touch it afterwards.
- when you wear your mask, be careful never to touch the front of your mask, as it may contain viral particles, or you may contaminate it. If you accidentally touch it, wash your hands as a precaution.
- remove the mask from the back, touching only the elastics or straps to avoid any risk of contamination.
- Place the used mask directly in a closed rubbish bin if it is disposable, and if it is made of cloth in a well-sealed bag or directly in the washing machine.
- wash your hands after removing the mask
- Decontaminate the mask if it is recyclable.
Beware of corona traps
- not taking off the mask to talk. It is precisely while talking that many droplets are emitted!
- do not put the mask around your neck, on your forehead, or pull your nose out of the mask, as this may infect you with particles deposited on the outer surface of the mask. A mask cannot be put on halfway: a mask that has been used and removed must be discarded or cleaned.
- do not cross the straps at the back of your head, as this can deform the mask.
- do not tie a single strap behind your head: the air passage potentially containing the virus will not be blocked!
- don't think you don't need a mask if you don't cough. We're most often contagious without knowing it. People who are asymptomatic (without fever or cough) can carry large amounts of the virus if they have been recently infected and, thus, transmit COVID-19 to others.
- do not cough into your elbow when you have a mask on because you may deposit viral particles on your elbow. Preferably turn your head and cough/sneeze in a direction where no one is facing you. Masks protect against droplets emitted when speaking but less when coughing or sneezing.
- do not use a mask for an entire day. All masks, including cloth masks, should be used for about 4 hours and no more, to avoid moisture retention, potential allergy risk and reduced filtration.
- do not touch your mobile phone with the mask: if you cannot avoid calling, do so with headphones or speakers if possible - decontaminate your mobile phone and hands afterwards.
Sources
The adhesion of the mask to the face is crucial: a 0.635 cm2 hole on a 59 cm2 mask reduces filtration efficiency by up to 60%.
Konda, A., Prakash, A., Moss, G. A., Schmoldt, M., Grant, G. D., & Guha, S. (2020). Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks. ACS Nano. doi: 10.1021/acsnano.0c03252Fine droplets carrying pathogens emitted by a sneeze can travel up to 8 meters in a few seconds/minute through a room.
Bourouiba, L. (2016). A sneeze. New England Journal of Medicine, 375(8), e15.N95 (FFP2) masks can be decontaminated up to 5 times at 85°C for 30 min (60% humidity).
Anderegg, L., Meisenhelder, C., Ngooi, C. O., Liao, L., Xiao, W., Chu, S., ... & Doyle, J. M. (2020). A Scalable Method of Applying Heat and Humidity for Decontamination of N95 Respirators During the COVID-19 Crisis. medRxiv.Comparison of the effectiveness of N95 surgical gauze ("gauze masks") and non-woven ("spunlace masks") masks after decontamination using dry heat (rice cooker), wet heat (autoclave), bleach, isopropanol, or ethanol.
Lin, T. H., Chen, C. C., Huang, S. H., Kuo, C. W., Lai, C. Y., & Lin, W. Y. (2017). Filter quality of electret masks in filtering 14.6-594 nm aerosol particles: Effects of five decontamination methods. PloS one, 12(10).The viral load in asymptomatic patients is similar to that in symptomatic patients.
Zou, L., Ruan, F., Huang, M., Liang, L., Huang, H., Hong, Z., ... & Guo, Q. (2020). SARS-CoV-2 viral load in upper respiratory specimens of infected patients. New England Journal of Medicine, 382(12), 1177-1179.Viral particles can be detected at low doses outside the mask after 7 days (0.1% of the initial concentration).
Chin, A., Chu, J., Perera, M., Hui, K., Yen, H. L., Chan, M., ... & Poon, L. (2020). Stability of SARS-CoV-2 in different environmental conditions. The Lancet Microbe.A study that compared the prolonged use of a cloth mask over a whole day versus the successive wearing of 2 surgical masks in a hospital in Vietnam. Cloth masks have a higher risk of infection than medical masks due to moisture retention, the potential reuse of poorly washed cloth masks, and less filtration.
MacIntyre, C. R., Seale, H., Dung, T. C., Hien, N. T., Nga, P. T., Chughtai, A. A., Rahman, B., Dwyer, D. E., & Wang, Q. (2015). A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ open, 5(4), e006577.