DO AIR PURIFIERS REDUCE CO2?

The filters within an Air Purifier do not reduce CO2 in their own right, as this particular gaseous pollution is simply way too small to be caught in any filter, no matter how minute the filter media is.

Air Purifiers with HEPA filters are designed to capture particulate matter, airborne pathogens and some toxic gasses, whereas increased ventilation is the best way to reduce CO2.

Indoor CO2 ppm levels is a proxy measure for how much of other people’s air you’re breathing (ie – a covid risk). It is also true that your thinking gets hazier when CO2 levels reach 1000ppm +.

If you are in a room where you can’t increase ventilation easily, either mechanically or by just opening a window for example – an air purifier is essential to help trap pollutants, allergens and airborne pathogens to reduce infection risk, or your respiratory system being contaminated with particulate matter.  An air purifier will also increase the air flow within a space significantly, which can have a secondary impact of reducing CO2 marginally.

Whilst the above is a summary, It’s helpful to understand the risks associated with high levels of CO2 and how you can take steps to reduce it. Read on to find out more….

What is CO2?

Carbon dioxide is a gas consisting of one part carbon and two parts oxygen. It’s natural and harmless in small quantities, but as levels rise it can affect productivity and health.   Carbon Dioxide is most commonly produced indoors by the air we exhale, and the levels tend to concentrate and rapidly rise indoors when there is less ventilation.

Where does CO2 come from?

High levels of indoor carbon dioxide concentrations are often driven by a combination of outdoor CO2 levels, people breathing ins shared spaces and the ventilation rate of the building.   Many HVAC and ventilation systems we use today will tend to recycle air to conserve energy.  Unfortunately the bi-product of this is that you essentially just keep moving contaminated air around a space rather than bringing in new/fresh air from outside.  This generally results in high CO2 concentrations and poor indoor air quality – as the air is not being changed meaning airborne pathogens and particulate matter stay suspended in the air being breathed in a shared space.

Is Carbon Dioxide (CO2) toxic?

Yes it can be. High levels of CO2 will change how the body functions and very high levels can cause severe, even fatal outcomes. Furthermore, high levels of CO2 concentration in poorly ventilated areas significantly increase the likelihood of being contaminated by airborne viruses such as Covid, harmful particulate matter and other indoor air pollutants.

What are the safe & dangerous levels of CO2?

Anywhere between 400-1000 parts per million (ppm) is generally regarded as safe and acceptable.  If the PPM reaches near to 40,000 this will cause unconsciousness or death.  Recent research has revealed that our decision making starts to falter at relatively low levels of around 1000-1500 ppm, which unfortunately is often at the lower end of the scale in many indoor settings. Productivity levels drop significantly and the ability to make decisions and think clearly is compromised.  Outdoor CO2 levels are typically around 400 ppm for reference.

What are the risks of high levels of CO2?

High levels of CO2 start off by causing confusion, headaches, fatigue and other neurological impacts. As the concentration levels increase, so do the implications on the body. At the upper end of the scale, Respiratory acidosis occurs when excess CO2 cannot be exhaled and is causing acid to build up in the body, which prevents your basic biochemistry from working properly.

Can plants help to reduce CO2?

Yes they can potentially reduce slightly through photosynthesis, but generally not enough to make a significant difference indoors.  Plants breathe slower than humans and they do not require energy to move around (funnily enough).  In summary You would need A LOT of plants to make a decent reduction on CO2.  Also, depending on the plant it may not remove CO2 without sufficient natural light.

What are the best ways to reduce CO2 then?

Firstly – invest in a CO2 monitor so you can keep a close eye on your indoor air quality.

Increase ventilation – open doors and windows, or invest in mechanical ventilation to bring in constant supplies of fresh air which is likely a more practical option in cold or hot climates.

Even opening a window for a few minutes can replace significant amounts of air in a room and help reduce CO2 levels towards outdoor levels.  

If you can’t easily introduce fresh air into a space, an air purifier is essential for infection and contamination prevention, and to ensure the harmful particles that are suspended in the air when there are high CO2 levels, are filtered out before you breathe them in.

An air purifier is a lot more affordable than costly upgrades to HVAC systems, and is why they are being widely implemented in schools and healthcare to reduce the risk of airborne infection spread.

Interested in finding out more about what you can do to improve indoor air quality?

Browse our Learning centre or book a call with an advisor!