High Level Photohydroionisation Air Purification Recommended By ASHRAE


The air we breathe indoors can circulate harmful viruses if not properly controlled, especially in buildings where many people are constantly mobile. In buildings such as offices, cinemas, shops and schools, the circulating air can be a big factor in spreading diseases such as COVID-19.

Modern air circulation systems can be a beneficial asset to our coronavirus strategy. Over the past 20 years, systems which include photohydroionisation technology have been developed to kill harmful viruses before they get the chance to enter our bodies and wreak havoc.

What Is High Level Photohydroionisation Air Purification?

Harmful bacteria, mould spores, viruses and unpleasant odours can be present in the air around us before eventually landing onto a surface. High level photohydroionisation air purification is a technology developed to both minimize and neutralise these using suitably equipped air-conditioning systems equipped.

High level photohydroionisation air purification is a solution that is based on advanced photohydroionisation technology. It works using UV light and quad metallic catalysts to destroy the living bacteria or virus, yet is totally harmless to humans, animals and plants.

The reaction created by high level photohydroionisation air purification results in the release of compounds that will come into contact with harmful bacteria in the air and neutralise them by damaging their cell structure, therefore making the air safe.

This technology is implemented into BMS systems to make sure that air circulated in rooms has been treated to remove deadly viruses like coronavirus.

Who Is ASHRAE And What Do They Do?

ASHRAE stands for The American Society of Heating, Refrigerating and Air-Conditioning Engineers. They are a professional association who seek to advance the design of heating, ventilation, air-con and refrigeration with a clear emphasis on human health and environmental sustainability.

ASHRAE operate in over 132 countries all over the world and serve over 57,000 members including building services engineers, mechanical contractors, building owners and architects amongst many others.

This society funds research projects, educational programs and publishes technical standards in order to actively improve our built environment, energy efficiency and indoor air quality. Their mission is to ‘serve humanity by advancing the arts and sciences of heating, ventilation, air conditioning, refrigeration, and all their allied fields’.

ASHRAE provides guidance and develops standards that are intended to mitigate the risk of transmission of infectious diseases in our buildings. The guidance they provide can be used in spaces such as offices and homes, as well as planes, trains and cars. This is generally classed as infectious aerosols and indirect transmission, as opposed to direct contact.

With the ongoing COVID-19 pandemic, ASHRAE’s Executive Committee and Epidemic Task Force have stated that the transmission of SARS-CoV-2 (COVID-19) through the air is likely, therefore changes to building operations such as airflow circulation, heating and ventilation systems should be addressed. ASHRAE have stated that the transmission of the COVD-19 virus can be reduced with correct circulation, ventilation and air filtration systems.

ASHRAE have also stated that unconditioned spaces can causes thermal stress to anyone inhabiting that space, which may lower resistance to infection. The disabling of circulation, heating, ventilation and air-con systems is therefore not a recommended way to control the virus.

What Airflow Methods Do ASHRAE Recommend?

ASHRAE state that proper airflow circulation, ventilation, filtration and distribution systems alongside disinfection technology have the potential to help stop the spread of diseases such as coronavirus. They can limit the transmission of airborne pathogens and therefore break the chain of infection.

Airborne pathogens are released through droplets and aerosols, typically by coughing, sneezing, talking, breathing, singing, toilet flushing and as a result of some medical procedures.

To help combat the spread of these, ASHRAE specifically recommend:

  • Upper-room UVGI with possible in-room fans as a supplement to supply airflow, whilst offering temperature and humidity control.

What Other Recommendations Does ASHRAE Provide For Virus Protection?

There are many factors to consider in the design and operation of your HVAC system in regard to minimising the spread of harmful bacteria. Various strategies have been found to be effective at the control of virus transmission, including (but not limited to):

  • Optimised air flow patterns
  • Zone pressurisation
  • Directional airflow
  • Dilution ventilation
  • In-room air-cleaning systems
  • The control of indoor temperature and humidity
  • UVGI

The operation and implementation of HVAC systems are only one part of the infection control strategy, and other measures should be taken alongside it such as social distancing, Perspex screens, regular handwashing, and one-way walking systems.

What Is UVGI?

Ultraviolet germicidal irradiation – otherwise known as UVGI – is a method of disinfection that uses UV light to kill or neutralise organic microorganisms. Short-wave ultraviolet light rays are used to disrupt or destroy the DNA of bacteria, rendering them useless and therefore unable to enter our bodies.

We are not exposed to UV light usually, because the ozone layer blocks these particular rays. This means bacteria and mould spores can survive in our atmosphere. By producing these rays through technology, we can directly target objects or the air that enters rooms in order to sanitise the environment.

UVGI is used in many ways, for example to disinfect food, air, water and surfaces. It has been used as a disinfection method for over 50 years, primarily in medical sanitation and work facilities that require sterilisation, and subsequently to disinfect drinking water and wastewater. In the past 20 years, it has been implemented successfully in air purification systems to disinfect the air within buildings.

UVGI can be installed as an air-conditioning unit, either as a new system entirely or to enhance the system you already have in place.

What Are The Benefits Of UVGI?

High power UVGI systems are installed inside air-conditioning systems and work alongside the cooling coils to break down the DNA of any virus. This means it improves the cleanliness of your air supply and stops the spread of harmful virus cells, therefore stopping the chain of infection and ultimately, keeping people healthy.

The system is effective at killing hazardous microbiomes as well as improving air quality in general, due to additional temperature and humidity controls. UVGI is microbiocidal and is effective as part of your on-going strategy to help control infectious diseases such as COVID-19.

It should be considered an important factor alongside traditional cleaning and disinfection, although it cannot be relied upon solely to control hazardous bacteria, it is a highly recommended addition to any health and safety strategy.

Talk To Airius About High Level Photohydroionisation Air Purification Systems For Effective Virus Control

If you would like to find out more about how high level photohydroionisation air purification systems can benefit your workplace or home, please contact us today for further information. We would be pleased to answer any questions you may have.

You can get in touch with us by calling on 01202 554 200 or via email at info@airius.co.uk