How do viruses like COVID-19 or Sars-CoV-2 spread through the air?

In this article, we will discuss the spread of viruses such as COVID-19 and the applications of HEPA and ULPA filters.

How do viruses like COVID-19 or Sars-CoV-2 spread through the air?

Viruses are naturally sub-micron in size - we are talking about 500 nanometers (0.5 microns) and smaller. The Coronavirus COVID-19 has a diameter of approximately 0.125 microns.

Even viruses in small quantities entering the body can already cause an infection.

COVID-19 is a specific virus that mainly spreads by attaching to secretions generated by the saliva, coughing or sneezing of an infected person. These droplets carry the bacteria and viruses and are thus the carriers of the virus. In addition, it can be found on surfaces infected if not properly cleaned or wiped, as well as in humid air environments, if not properly filtered.

What are the symptoms of coronavirus (COVID-19)

• Fever
• Dry cough
• Shortness of breath
• Cold complaints (sneezing, sore throat, runny nose, cold in the nose)
• Pain in the body
• Temporary loss of taste and / or smell
• Headache
• In some cases, coronavirus COVID-19 can cause serious breathing problems, kidney failure, or death.

Are HEPA filters capable of filtering the COVID-19 virus?

There is currently not enough research to verify whether a HEPA filter reduces the transmission of COVID-19. If we look at comparable viruses such as SARS that are effectively captured by HEPA filters, it is very likely that the HEPA filter can also be used extremely effectively for COVID-19 in many situations.

We can make this assumption because the virus is mainly excreted and spread by sneezing and coughing in the form of biological aerosols, ranging from 0.5-3 microns.

How does HEPA filtration work?

HEPA filters consist of a complex blend of filaments and fibres carrying a static charge that attracts various microbes and particles.

HEPA stands for High Efficiency Particulate Air and is a filter classification that captures microbes, dust and particles larger than 0.3 microns with an efficiency of up to 99.97%.

While the particles are drawn in through the air filter system, they are captured and retained in the filter. In addition, an interesting scientific effect known as Brownian Motion occurs, where particles bounce around in a certain state and get trapped.

NASA research has shown that sub-micron particles up to 0.1 micron are extremely effectively captured. Taking into account all tests are performed with new filters while HEPA filters actually work better the more they get dirty, there is no doubt the filter will perform even better. HEPA filters not only capture viruses, but also ensure a cleaner living environment.

How can a HEPA filter help reduce the spread of the COVID-19 virus?

Theoretically, it is impossible for a HEPA filter to effectively trap 100% viruses as many microbes are less than 0.03 microns in size. This size however is in an isolated form in which the virus cannot survive long. In practice, the viruses are bound to a carrier, which results into an efficiency of a HEPA very close to 100%.

We would like to emphasize that a HEPA air filter is not a final solution. After all, it can only filter particles that it is actually sucked in via forced air. Many airborne particles can still float freely before finally reaching the air purifier.

Therefore, adherence to the correct procedures remains necessary. Wearing masks and gloves and following the general guidelines, such as coughing and sneezing in the elbow, washing / disinfecting hands regularly, not shaking hands and respecting the 1.5 meter social distance. The use of a HEPA filter in combination with all these procedures ensures that the virus can spread considerably less easily.

Breathing mask

Health professionals are recommended to wear N95 respiratory masks to protect them from COVID-19. These protective masks provide a much closer fit on the face than standard face masks. The designation "N95" means that the mask has been tested to filter at least 95% of the 0.3 micron particles. When used correctly, N95 respirators filter airborne particles extremely efficiently.

Higher quality filter solutions for the Coronavirus ULPA Filters

ULPA filters are available for even higher quality air filtration. The ULPA filters have an efficiency of up to 99.9995% on particles down to 0.12 microns, where HEPA filters achieve an efficiency of up to 99.97% on particles up to 0.3 microns. ULPA filters have a MERV rating of 20, while HEPA filters are rated MERV 17. The higher efficiency allows ULPA filters to capture more of the smaller respiratory aerosol particles that contain the coronavirus and possibly even some of the coronavirus particles.

Please feel free to contact us for information about our HEPA and ULPA filters and our Hepafilter air purifiers. info@allsorb.com or +31 229 263004.