< 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

Beware of corona traps

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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.0c03252

Fine 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.

Further reading

Why put on a mask?

Do I have to wear a mask if I don't have any symptoms?

Can a mask be reused?

How do you make your mask?

What are the different types of masks?