What are the keys to properly ventilating closed environments and avoiding contagion by COVID-19

Although the recommendation of health authorities is to spend as much as possible in open spaces and outdoors, It is inevitable to carry out in these places certain activities which take place inside.

For this reason, it is essential to refresh certain recommendations to minimize the risk of contagion against COVID-19 but also to take into account the optimization of the air breathed.

“Clean or fresh air is free of particles and irritants“, He explained Mario lead, President of the Society for Residential Medicine, Building Hygiene and Indoor Toxicology in Germany.

Outdoors, the air you breathe is constantly in motion and mixes quickly, while in closed rooms it stays more or less still. This is what allows pollutants or even viruses to concentrate there which would have quickly spread in the atmosphere outside..

Exhaled carbon dioxide can also be troublesome. In that sense, it can withstand up to 1000 ppm (parts per million) in the environment, the university professor said. Klaus Fiedler, who wears 40 years of research in the field of hygiene and residential medicine.

But that value can be quickly exceeded, said Fiedler, who gives as an example the situation of two people sleeping in a small room with windows tightly closed.

According to the professor, more than 2000 ppm of carbon dioxide could be reached overnight. The next day, these people could suffer the possible consequences, such as headaches, fatigue or reduced ability to concentrate.

“Ventilation of confined spaces, such as offices, cars, homes, schools and public transport, is essential today to control the pandemic“, He told Infobae José Luis Jimenez, Professor of chemistry at the University of Colorado in Boulder, United States, who is among the group of 239 scientists who told the WHO last year it should consider the coronavirus to be transmitted by air as well, and is among the specialists who signed the recent article published at The Lancet which gathers overwhelming evidence that the main mode of transmission of the coronavirus is by air.

“Why are we still in a pandemic? One of the reasons is that a person can be infected with the coronavirus and not have any symptoms. But when you breathe out or speak, it emits aerosols containing the coronavirus. The problem is that other people see that person as a healthy person and if they share a space like an office, school, or transportation, they can contract the infection.. It’s still hard to recognize that the coronavirus is also in the air, ”said Jiménez, a doctorate in mechanical engineering from the Massachusetts Institute of Technology (MIT).

Air several times a day

“People often don’t even know when to broadcastFiedler alerted. “Often the air is only stale when the contrast occurs, after arriving from another room.” For this reason, he advises trying to completely change the air in the room by ventilating three times a day.

It should be borne in mind, especially given the coronavirus, that air filters in the room cannot replace constant ventilation.

As explained in September 2020 at Infobae Jimenez, Being outdoors, wearing a chin strap and maintaining social distance are the 3 keys to curbing COVID-19 infections.

Regarding the SARS-CoV-2 virus, he said:From a technical point of view, it is a virus which is transmitted by this aerosol route and a little on surfaces; it’s hard to understand because it’s not super contagious. Medicine and epidemiologists believe that if a virus is transmitted by air it must be very contagious and it is a mistake of history, they have denied that any diseases or viruses are transmitted by air and did not proved that those who were very contagious. “.

Aerosols “are small particles, small pellets of material, saliva or respiratory fluid., -the liquid that wets our lungs which is basically mucin and sodium chloride- and they come out when we speak or when we breathe and float in the air– the bigger drops also come out which fall to the ground within a meter or two – but much smaller particles also come out that we cannot see and there may be a virus there and then they stay floating in the air, and someone else can breathe and thus become infected, ”said the chemist, who according to the University of Colorado is the world’s fifth most cited scientist in geosciences over the past 10 years.

Pay attention to temperature and humidity

If you want to have a healthy environmental climate, you need to pay attention not only to the concentration of carbon dioxide and vapors, but also to humidity and temperature.

Air that is too dry can dry out the mucous membranes. “This makes it harder for the body to remove dust particles, bacteria and viruses inhaled,” Fiedler explained. “As a result, pathogens are easier to enter the body and a person catches a cold more quickly.”

Just put a bowl of water on the heater or some houseplants to ensure good air in the room. However, “if you have problems with too dry air, you better buy a good home humidifier», Advised the expert.

Whether or not these devices are used, in general terms, it should be taken into account that the humidity should not be too high. If the air in a room is too humid and condenses on cold walls, mold can grow.

Especially for people with allergies, asthma or other lung diseases, mold spores in the air can become a real problem.

But even for people without pre-existing conditions, the musty smell can be bothersome. Ideally, the relative humidity of the room should be between 40 and 60%.

Wide-open

Typically, mold grows on surfaces where moisture from the environment condenses. “For this, above all after cooking or showering, shock ventilation is important“Said Mario Blei.

If the windows are opened wide once, moisture is transported to the outside more quickly. That subsequently the space warms up, producing comfortable heat again is also an important parameter for health, insists the expert.

Normally, most people are more comfortable in a temperature between 20 and 24 degrees Celsius. However, Fiedler rightly notes that the feeling of hot or cold is very individual.

Drafts or cold walls can also make the person cold and uncomfortable, even if the air in the room is really hot.

How to ventilate properly?

Experts recommend ventilating three times a day. To do this, you must open all the windows fully. The fastest way to regenerate air is through cross ventilation. To do this, the opposite windows are wide open and, if necessary, the doors between the rooms.

In winter, 3 or 4 minutes is enough because of the big temperature difference between inside and outside. In summer, it may take 15 minutes or more to completely change the air in the room.

It is important to note that in case of high humidity concentration, for example after showering, shock ventilation in the room is preferable. This means the window is wide open, but the door is closed. This prevents humid air from reaching other rooms.

Experts recommend ventilating three times a day

Experts advise against tilt-and-turn windows. When it is cold outside, the window header becomes so cold that moisture in the air in the room condenses on it, which can lead to mold growth.

When it is warmer outside, the window may be left open a little, but the ventilation effect is minimal due to the small opening and the lack of temperature difference with the air in the room.

KEEP READING: