Managing Covid-19 transmission during the winter will not be an open and shut case!

Managing Covid-19 transmission during the winter will not be an open and shut case!

According to guidance by the UK Scientific Advisory Group for Emergencies (SAGE) and the Chartered Institution of Building Services Engineers (CIBSE), increased ventilation, through such means as opening windows, should keep coronavirus cases low and “reduce the risks of airborne infection.”

Yet coronavirus cases have risen in all but two UK regions according to recent figures from Public Health England. These troubling statistic makes one thing very clear: ventilation clearly isn’t sufficient as a means of slowing the transmission of COVID-19. The average daily case rate now is far higher than it was a year before.

If cases are continuing to rise despite the doors and windows of a whole nation being open, then a focus on ventilation is perhaps myopic or even looking up the wrong avenue, and – in its energy costs – forces the country to take backward steps in terms of achieving net zero emissions and improving productivity.

At a time like this there should be focus on other methods and technologies that are proven to reduce or eliminate indoor viral transmission. Ventilation, filtration and UVGI are passive methods that rely on moving live viral particles to the point of treatment or removal and that is where the risk lies and explains why we always see R rate increases when we relax from lockdowns. Put simply they don’t destroy the virus instantly and until we deploy a process that does the threat of increased infections will remain.

One technology process that works like this is Photohydroionisation (PHI). It is proven to destroy SARS-CoV-2 viral emissions instantly and continuously throughout entire indoor environments at the point of transmission, yet there is a lack of recognition of PHI in CIBSE’s latest publication on air cleaning technology.

Omissions in CIBSE guidance

CIBSE’s most recent ‘Air cleaning technologies’ paper asserts that the operative principle “of each type of device has been described in detail in previous papers” including a 2020 SAGE-EMG publication but there is no mention of PHI in that paper.

It further asserts “air cleaners could be part of the solution in minimising risks […] but they are not a solution that reduces all risks,” and that “increased ventilation” remains the “primary” means to reduce far field airborne spread. In fact, equilibrium PHI is proven to be effective throughout the entire air and surface space simultaneously and continuously and as such, there simply is virtually no far field risk in buildings fitted with PHI technology.

Further, it cites “limited evidence” of air cleaners’ efficacy without acknowledging independent studies on PHI by Innovative Bioanalysis which proved its effect at eliminating continually introduced aerosolised SARS-CoV-2 throughout a real world sized test chamber. The results demonstrated a greater than 3.5/4+ log continuous neutralisation of airborne SARS-CoV-2 virus particles and aerosols. This world first testing pioneered a year ago in 2020 has since spawned interest from US government bodies and today the manufacturer, RGF Environmental, is helping to advise on new industry protocols for microbials and technology testing.  This most compelling evidence has simply been ignored.

Towards an effective solution

It is fair to say that CIBSE and SAGE’s guidance is one dimensional and perhaps even myopic in terms of optimal mitigations for deadly viruses. No passive method will kill viruses instantly so by definition they are simply not the safest or most effective approaches. They do provide some benefit but its like closing the gate after the horse has bolted. You’ve already caught the virus by the time it reaches the window, filter or UVGI system.

With lives and our economic prosperity at stake, it is vital to challenge and consider safer and more effective alternative methods like PHI that don’t penalise energy efficiency or productivity. With this in mind it is feasible the COVID guidance measures could be re-prioritised as PHI is independent and not reliant on ventilation air change increases and there is a very strong argument they should be as we prepare for the colder months where infections will increase and homes and businesses face massive energy cost increases as a consequence of following the current guidance.

Published at Fri, 03 Sep 2021 06:21:29 +0000

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