Airborne particles are floating in the air constantly; many we can see, like pollen and pet dander, while others are too small to see with the human eye.

To demonstrate particle sizes, the image below shows them in relation to a human hair measuring roughly 70μm. Our bodies can prevent particles of PM10 and above from entering our system, thanks to the work of our nose, hair, eyelashes, and lungs. But anything smaller can be inhaled and, as we each breathe around 22,000 times a day, that can mean a lot of unhealthy particles entering our bodies.

Our indoor air quality can be up to 5 times worse than outside air due to off-gassing of furniture, flooring, carpets, chemicals used for cooking and in cleaning products (VOCs), mould, microbes, particles and odours. Lack of ventilation in our homes keeps these particles recirculating in the air.

Part F of the UK government building regulations has been updated for new residential buildings to incorporate ventilation. But what can we do about existing homes?

Some top tips

• Keep windows and doors open when cooking or cleaning.
• Use your kitchen extractor fan and check, clean or replace your filter
• Reduce dust by using a damp cloth
• Vacuum curtains and upholstery (and your car).
• Wash bedding and toys weekly in high pollen season.
• Use chemical-free cleaning products.
• Indoor plants can help to improve the quality of indoor air.  

• You can also consider indoor air sensors. There are different types on the market, from measuring CO₂ in the home to expensive ones that can also measure temperature, PM and other gases.

• Air purifiers can be great for hay fever and allergy sufferers, although prices do vary considerably.

If you have a particular allergy – such as pet or pollen, make sure you look at air purifiers that are right for you.

Understanding filter grades.

Common air particles also referred to as contaminants, are captured on the below class of filters.

Coarse – Hair, sand, plant spores, textile fibres, water droplets

ePM10 – Spores, sediment, large bacteria and germs, ePM10-sized dust.

ePM2.5 – Soot, ePM2.5-sized dust.

ePM1 – ePM1-sized dust, oil, smoke, bacteria

E [EPA filters] – Germs, tobacco smoke, viruses being carried on particles, carbon black

H [HEPA filters] – Aerosol microparticles and viruses

U [ULPA filters] – All air suspended particulate matter

A [Gas filters] – VOCs, solvent vapours, kitchen odours, NOx and other gases (this type will be used in your kitchen extract fan).

Improving home or office indoor air quality is vital to our health, as air pollution dirties every organ in the body.