Clean air is the NHS’s most powerful weapon against Covid-19

July 6, 2021 – 3 Min

The impact of Covid-19 on the NHS has been devastating and it has now been reported that it could take up to five years to clear the backlog. If the country suffers from further waves caused by new variants, waiting times could extend even further.  

People are calling for a bold, transformative approach to resolve this crippling issue. Clearly,  a raft of measures is needed, both financial and operational. If the NHS is to live long term with Covid, it needs to cover all the bases: not just the complex issues like human resources and capacity increases, but simpler issues too. 

Simpler issues like clean air to prevent airborne transmission, which is now accepted as the greatest risk. Airborne transmission is a major issue for hospitals, yet many struggle to meet the NHS’s own ventilation guidelines of 6 air changes per hour. 

Clean air solutions can not only be a quick fix, but are arguably the most potent weapon in the battle against Covid. That is, of course, if they are specified correctly. 

The WHO recommends air purifiers to supplement integrated ventilation systems while the SAGE committee, in its November 2020 report on air cleaning devices to combat SARS-CoV-2 transmission, recommends two technologies: fibrous filtration (HEPA) and germicidal UV (UVC), which together trap and destroy the virus. 

Further evidence of the efficacy of HEPA filtration and UVC light is available from trusted sources. The diameter of the SARS-CoV-2 virus has been found to range between 0.05 to 0.14 microns and research by NASA proves that HEPA filters are most efficient at capturing ultrafine particles below 0.3 microns in size, as well as larger particles. The larger sizes are potentially even more important as the virus is carried in airborne aerosol droplets, over 10 microns in size, that protect it from evaporation. Having trapped the virus, it must then be destroyed: a recent study by the Henry Ford Health System shows that UVC light is effective for killing Covid-19 on N95 respirators. 

SAGE also stresses the importance of independent laboratory testing of air purifiers to ensure efficacy and avoid any side effects, such as respiratory problems or skin irritation that might occur from by-products released from the filtration system. 

In March 2021, the Danish Technological Institute (DTI) conducted rigorous tests on the Rensair air purifier. The objective of the first DTI test was to determine the unit’s efficacy in reducing the concentration of active aerosolized MS2 bacteriophages (used as a proxy for SARS-CoV-2), deploying a modified ISO 16000-36:2018 method. The result was a particle reduction rate of 99.98 % in 15 minutes and above 99.99 % in 30 minutes. The second test was to determine the virucidal activity of the unit’s UVC photolysis system. The result was that the concentration of viable MS2 virus that could be recovered from inside the HEPA filter after use was below the detection limit for the analysis, thereby demonstrating wholesale destruction of the virus. 

Since the threshold for Covid-19 infection is estimated at only 300 virus particles, compared to a typical inhaled viral infection requiring 1,950 to 3,000 particles, the argument for air purification is an open-and-shut case. 

NHS Providers’ chief executive, Chris Hopson, has warned that the backlog in the NHS is not just about elective and cancer in acute hospitals, but also patients and service users waiting for mental health and community service. While the solution calls for revolutionary thinking, there are some easy fixes that are merely evolutionary. 

One such easy fix is portable, hospital-grade air purification. High performance, cost-effective and simple to install. Job done.

covid-19 DTI hepa hepa13 hospital grade air purification N95 NASA NHS Rensair SAGE SARS-CoV-2 uvc WHO

Get a quote

Describe your needs and get your quote within 24 hours

Get a Quote

Talk to an expert

Book a free consultation with one of our technical experts

Book Consultation

Looks like you're visiting Rensair from the US. We recommend that you go to our dedicated US site


It looks like you are visiting Rensair from the Hong Kong region. We recommend that you go to our dedicated Hong Kong site.