5 keys to monitor the air we breathe indoors and avoid covid-19

Staying in a place with poor air circulation for a long time can be risky.

With the return to classes and offices in many countries, preventing the spread of the coronavirus inside buildings has become a key issue.

For months we have been told to wash our hands and maintain social distancing to avoid SARS-COV-2 that causes the covid-19 disease.

But scientists and engineers say that too we must think about the air we breathe, as children return to classrooms and more people return to their jobs.

There are 5 key aspects to consider.

1. If it’s stuffy, stay away

When you walk into a room and the air feels stale The loaded, something is wrong with the ventilation.

Not enough fresh air is getting in, increasing the chances of getting infected with coronavirus.

Recent research shows that in confined spaces there may be a “airborne transmission” of the virus, as there are small particles of the pathogen that remain in the air.

It is important to be aware of the quality of the air you breathe indoors.

So fresh air intake is more important than ever.

So if a place is stuffy, you have to turn around and leavesays Dr Hywel Davies, technical director of the UK Chartered Institution of

Construction Services Engineers.

Clean airflow is vital: “If someone is infected in a building and enough air is coming in from outside, any infectious material that is spreading is diluted. The risk of other people being infected is being reduced.”

2. Monitor the air conditioning

From offices to shops, air conditioning is welcome on hot days, but it is important to know what type of appliance there is.

The simplest, known as air conditioning split, takes air from a room, cools it, and then expels it again.

In other words, it is recirculating the air. This is not a problem if you visit a place quickly. But it can be a risk if you are in place for several hours.

A study of a restaurant in China, published by the US Centers for Disease Control and Prevention, showed that this type of air conditioning played a key role in the spread of coronavirus.

In the establishment there was a “presymptomatic” customer, that is, someone who was infected but did not realize it because he had not yet developed symptoms.

Scientists consider that released the virus by breathing and speaking. The pathogen was spread around the place through air currents from the split on the wall.

The result was that other nine people were infected.

Davies insists on the importance of fresh air: “If there had been a good supply of outside air, it is very likely that fewer people would have been infected.”

3. Find out about the ‘fresh air ratio’

In a modern building where the windows are sealed, how can you get enough fresh air?

The most common is to have a ventilation system in which stale air is extracted from the rooms and channeled to a treatment unit, often located on the ceiling.

In these places, fresh outside air is brought inside and combines with the air from inside. What you breathe is a mix of that.

Given the risk of coronavirus infection, the professional advice is to maximize the fresh supply outside.

“Have 100% outside air or close to 100% is a good thing“says Professor Cath Noakes of the University of Leeds (UK).

“The more fresh air, the lower the risk that the virus will circulate again in the building,” he adds.

The precise combination is often in the hands of the building managers.

But the downside to running 100% fresh air is the cost: the incoming air has to be heated in winter and cooled in summer, all which requires energy.

4. Check the filters

A modern ventilation system must have filters, but these are not infallible.

Researchers in the US who studied what was happening at Oregon Health and Science University Hospital found that the filters trapped traces of coronavirus, but some were able to escape him.

Professor Kevin van den Wymelenberg, who led the project, believes that cleaning the filters could reveal if someone is working in a building infected.

In South Korea, a telephone operator company located in an office building detected that a person was capable of infecting more than 90.

If the filters had been checked more frequently, the presence of the virus could have been detected earlier.

Van den Wymelenberg says the information from the filters can “show us where to attack and when” to fight infections.

5. Be careful with drafts

Any expert in the field says it: fresh air is the key. But a specialist in modeling the movement of air adds that It is not so simple.

Nick Wirth used to work on Formula 1 car design and now advises supermarkets and food processing companies on how to manage airflow to keep people safe.

Warns that if someone is sitting next to an open window and is infected, they could transmit the virus to others in the direction of the wind.

“If you open a window, where is the air going to go? You don’t want people in a direct line of that air flow,” he explains.

“More fresh air is generally better, but if it flows horizontally and is full of viruses, could have unintended consequences“.