As we continue to grapple with COVID two very clear future objectives have emerged:
- The need for safer and healthier indoor environments to protect against SARS-CoV-2 and other infectious microbial.
- Acceleration of UK’s net zero by 2050 plan - 78% reduction by 2035 compared to 1990 levels.
Last week a group of world-renowned scientists published a paper entitled ‘A paradigm shift to combat indoor respiratory infection’ affirming the need for improved building ventilation systems to deliver better more effective control of the indoor infectious transmission. This paper proposes increased ventilation rates and the distribution of‘ clean disinfected air’ and the use of ‘ultraviolet devices while avoiding unproven technologies.’
Energy efficiency improvements
According to UK GBC, the built environment contributes 40% of the UK’s total carbon footprint
Whilst we can all agree with the end game objective it must be noted that ventilation air change increases, which is the primary COVID mitigation, are likely to significantly increase the UK’s carbon emissions when we go back to work. Boris Johnson’s government announced on 20 April 2021 its plans to reduce carbon emissions by 78% by 2035. According to UK GBC, the built environment contributes 40% of the UK’s total carbon footprint and approx 80% of 2050 buildings have already been built.
Further, according to the Local Government Association, in order to achieve Net Zero by 2050 close to 28 million buildings will need retrofit energy efficiency improvements which will, in turn, need retrofit ventilation improvements to avoid consequential IAQ and health problems. Quite clearly, the challenge of decarburization of energy and heating and ventilation improvement is in existing property stock space and it is quite simply enormous - at least 1 million per year.
Ventilation improvement strategies
We have been focused on making buildings more energy-efficient for years by specifying or retrofitting improved insulation characteristics but in many cases, this has resulted in under ventilation and created consequential issues of IAQ and related health problems especially in naturally ventilated buildings which are the predominant strategy for domestic properties. This has created an increased demand for retrofit ventilation improvement strategies such as PIV and since the pandemic and the revelation that the primary transmission route is airborne, this demand has increased further.
This has created an increased demand for retrofit ventilation improvement strategies such as PIV
Official guidance states the primary mitigation is increased fresh air ventilation air changes with any mechanical recirculation processes turned down significantly or off altogether. At its heart is the logic that increased ventilation air changes beyond current levels will blow the virus away combined with turned off recirculation processes reducing the ability for the virus to spread thus resulting in an overall reduction of the risk of transmission.
Increased ventilation rates
Whilst fundamentally sound there are a number of consequential issues that must be recognized:
- Ventilation is a dilution/displacement process. It does not destroy viral emissions, it just blows live emissions around so the risk of transmission can arguably be increased if people are downstream. There are various academic studies that affirm this view such as the University of Oklahoma. Ventilation also provides no protection to surface contaminations.
- Increased fresh air ventilation rates make buildings significantly less energy efficient. Windows must be opened and left open for naturally ventilated spaces and mechanical systems must be turned up and all heat recovery processes turned off. This also makes buildings colder during colder months which affects occupant comfort, health, and productivity.
- Increased ventilation rates increase outdoor pollution ingress which can create similar consequential problems of IAQ and cause health problems or worse as the recent ruling by the Coroner in the case of Ella Adoo-Kissi-Debrah shows, whose tragic death was caused by an asthma attack brought on by air pollution.
Mechanical HVAC systems
This is not surprising considering one of the benefits of HVAC recirculation is heat recovery
Evidence from various UK corporates whose buildings incorporate ducted mechanical HVAC systems has shown that energy consumption across their estates whilst following official guidance has not just increased but has skyrocketed especially over the winter months. This is not surprising considering one of the benefits of HVAC recirculation is heat recovery. All of this heat recovery benefit is lost when following the official guidance.
Similarly, domestic homeowners and tenants especially whose properties are naturally ventilated would have seen increases in energy costs over the winter if leaving doors and windows open (although many would have chosen not to open windows when they know it will increase costs and make the property colder). Evidence, therefore, shows that from an energy efficiency and carbon footprint perspective we have been going backwards since the pandemic hit which begs the question. How is it going to be possible to meet the 2050 carbon reduction targets?
Air disinfection molecules
Just as we improved energy efficiency through insulation but created IAQ and health problems we are now improving (apparently) infection control at the expense of energy efficiency. What is needed is a strategy that delivers one AND the other not one at the expense of the other. A strategy that will effectively reduce the risk of infectious transmission in our indoor spaces without penalizing energy efficiency.
A strategy that will effectively reduce the risk of infectious transmission in our indoor spaces
Active air purification that creates a safe-to-breathe equilibrium concentration of natural air disinfection molecules throughout the indoor space offers a credible, realistic, safe, and affordable solution and is just as easily retrofitted as it is applied to new build. Photohydroionization or PHI is a tried, tested, and proven technology that achieves instant and continuous ‘point of transmission’ elimination of infectious microbials whether in the air or on surfaces.
Ingress outdoor pollution
PHI also instantly treats any ingress outdoor pollution such as particulates as well as indoor originated pollution such as odors, VOCs and allergens (pet dander, dust mite fecal matter). Developed and patented over 20 years ago in the US with over 5 million installations in over 60 countries around the world, PHI is designed for quick and easy retrofit into new and existing buildings, either integrated into any HVAC supply infrastructure or installed standalone on walls or ceilings.
PHI is probably the most scrutinized of all air purification technologies having been subjected to numerous safety and efficacy tests by nationally accredited labs and testing bodies over 2 decades as well as in real-world customer settings such as Lloyds of London. Its SARS-CoV-2 performance credentials are peerless with no equivalent in public health and academic settings, showing 4+ log continuous reductions over a 24 hour period against nebulized emissions every 15 mins throughout a 1,280 ft3 chamber.
Ionized hydroperoxide molecules
PHI works by mimicking Earth’s atmospheric air cleaning processes indoors
PHI works by mimicking Earth’s atmospheric air cleaning processes indoors. It produces an equilibrium concentration of ionized hydroperoxide molecules in similar concentrations to the outside air - 0.01-0.04ppm so is perfectly safe to breathe. These molecules are throughout the indoor environment which breaks down and destroys infectious microbials and other organics such as VOCs, odors, gases on contact before reverting back to harmless water vapor and oxygen afterward.
Most importantly PHI is not reliant on air movement to blow the live virus away or toward passive technologies like filters or UV so it does not penalize building energy efficiency. Indeed, PHI allows the continued safe use of HVAC recirculation processes because the equilibrium effect effectively disables the ability for any virus to transmit. PHI is also not behavior dependent and is constantly working in the background regardless of there actions or behaviors of building occupants. In other words, it provides a unique extra layer of protection to building occupants beyond the current mitigations.
Improved indoor protections
Given the fact that PHI equilibrium can achieve strategic and continuous protections throughout indoor spaces without relying on ventilation air change increases beyond current levels, it could be regarded as a more realistic strategy to achieve the objectives of improved indoor protections against infectious microbials and the 2050 carbon emission reduction targets.
PHI could be quickly and easily retrofitted into all existing buildings and indoor spaces
Further, PHI could be quickly and easily retrofitted into all existing buildings and indoor spaces and specified for all new builds going forward, thus achieving rapid transformation to safer and healthier indoor environments. Buildings with mechanical HVAC strategies that were meeting the requirements of Part F entering the pandemic i.e. almost every commercial building will not need ventilation air change increases for the purposes of infectious transmission control after PHI has been retrofitted.
Naturally ventilated buildings
Those that were not should be subject to an HVAC performance audit by a suitably qualified HVAC professional who would recommend improvements or a change to a new strategy. The UK’s 2050 energy efficiency targets will be best served if all of the UK’s approaching 28 million naturally ventilated buildings are retrofitted with energy efficient mechanical ventilation performance improvements. Positive Input Ventilation (PIV) is the go to strategy for these retrofits.
Unlike centralized Mechanical Ventilation with Heat Recovery (MVHR), PIV was originally conceived as an affordable retrofit strategy to solve condensation and mold problems without having to open windows. It is quick and easy to install and is one of the most common whole house strategies in the UK with millions of public and private sector installations dating back to the 1980s.
Mechanical ventilation performance
It will simultaneously improve IAQ helping to create the healthiest indoor environments
It delivers predictable and reliable mechanical ventilation performance at virtually no electricity cost, it increases ventilation air change rates without the need to open windows and it offers important energy efficiency benefits - energy recovery from solar gain amounting to approx 500kW per year according to Energy Saving Trust for lofted properties and optimized floor to ceiling heat distribution through destratification which optimizes thermostat controlled energy consumption.
To summarize, PHI’s tried, tested, and proven ‘point of transmission’ treatment of viruses and microbials will create the safest indoor environments it is possible to create without penalizing the enormous energy efficiency gains made over recent years which are now being eroded.
It will simultaneously improve IAQ helping to create the healthiest indoor environments paving the way for improved health, wellbeing, and productivity at home and in the workplace across our society.
