Are air conditioners good or bad for COVID-19?

Throughout the pandemic, we all quickly learned how fresh air and spending time outdoors limits the spread of COVID-19. However, with winter upon us, we’re all spending a lot more time indoors with others whether we’re at work, shopping, travelling, socialising or visiting leisure and entertainment venues.

Improving ventilation is key to making indoor spaces safer whether naturally by opening doors and windows or through mechanical means such as fans, air purifiers and air-conditioning units. However, while air purifiers have been scientifically proven to remove COVID-19, the same cannot be said for air conditioning. In fact, a question mark has been raised about whether it can increase the risk of catching bugs and viruses, including the coronavirus.

Can air-conditioning spread coronavirus?

The risk of air conditioning as a catalyst for the spread of COVID-19 was identified by scientists right at the start of the pandemic. A well-known example of this was the case within a restaurant in Guangzhou, China. This saw an outbreak from one asymptomatic, infected diner to two other families sat as far as four metres away. As COVID-19 is airborne, scientists report infected air droplets breathed out by the index patient were subsequently picked up by the air-conditioning unit and propagated across the restaurant, infecting others even though they were sat at what would be considered a ‘safe’ distance away.

Are air conditioners safe to use?

The short answer is; it depends which type you have. Some air conditioners, known as split units, simply recirculate the air the within a room. They work by drawing the air in, cooling it down and blowing it back out again. During this process, there is no fresh air supply or filter. Therefore, if someone is infected with COVID-19, there’s a risk the air-conditioning unit will accelerate the spread of infection to others within the room. This is different from air purifiers which physically clean the air, removing not only COVID particulates but also other pollutants, viruses and diseases such as flu, colds, measles and chicken pox.

What’s more, some air-conditioners also share their ventilation system with other units in different rooms, compounding the risk of exposure, breaking ‘bubbles’ and negating any protection from social distancing. And as infected airborne particles can linger within an indoor environment for up to hours at a time, the risk continues even after the sufferer has left the premises.

How do I know if my air conditioning is safe for COVID-19?

Adequate ventilation, such as open windows, is believed to lower the risk of cross-infection caused by split air-conditioning units. However, the Health and Safety Executive advises it’s better not to recirculate air from one space to another which intimates units which have a centralised ventilation system are not ideal. HSE also warn that recirculation units can mask poor ventilation as they only make an area feel more comfortable rather than improving air quality. If you’re not sure about which type of air-conditioning unit you have, or if it is effective enough in ventilating your building, get it checked before you use it again.

Is my building well ventilated enough?

The colder, wetter weather makes it harder for us to rely on opening doors and windows yet the sustained spread of the coronavirus means good ventilation is still essential. An easy way of measuring the effectiveness of your workplace ventilation is through carbon dioxide (CO2) meters, giving an indication of air quality. The higher the level of CO2, the more concentrated the air. From a COVID perspective, higher levels mean you’re more likely to be breathing in air someone has already breathed out. When you’re outdoors, the average CO2 level is around 400 parts per million (ppm). Indoors during the summer time when ventilation is naturally higher, CO2 levels average around 800 ppm – twice as concentrated as outdoor spaces. However, indoor spaces during the winter can see CO2 levels reaching as high as 1,200 ppm – up to three times more concentrated than outdoors and 50% more than the same space during the summer.

This demonstrates why it’s more important in winter to proactively improve air quality by ensuring an adequate supply of fresh air and increasing the number of air changes within a room with natural and mechanical means which complement each other.

Good ventilation not only helps to create a robust line of defence against the pandemic but also helps to tackle several workplace issues such as pollution which can be a serious health risk. Clean air can also boost productivity, improve concentration and reduce the risk from other diseases and viruses as well as allergens.

How can phs Compliance help?

phs Compliance can work with you to audit your ventilation and provide recommendations for a safer, healthier working environment.

With more than 40 years of experience, phs Compliance specialists not only provide expert advice but will ensure your business is compliant with regulations too including carrying out HSE-recommended maintenance checks on air-conditioning units. While we’re there, we can also conduct leak checks on air conditioning units as well as heat pumps, required by law on fluorinated gases which can be contained within refrigerant gas used for chilling and cooling. Leak checks involve direct methods of leak testing by inspecting circuits and components with an electronic gas detector, leak sprays, UV detection fluids and oxygen-free nitrogen to pressurise the circuit. Qualified air conditioning engineers will also record system pressures, temperatures, compressor-run currents and carry out visual inspections. phs Compliance engineers also inspect air handling units and Lossnay heat recovery systems.

Find out more about our air conditioning and heat pump checks and ventilation audits now by getting in touch with phs Compliance today.

To learn more about our what Compliance offers, to get a quote, or simply to ask a query, please feel free to contact us now!