What is indoor air pollution and why is it bad for your health?
Indoor air pollution comes from a huge range of activities – from cooking and cleaning to personal grooming. Whenever fine particles are released from such activities, air pollution is occurring.
According to the World Health Organization (WHO), poor indoor air quality has been linked to a range of illnesses, including asthma, pneumonia, lung cancer, and cardiovascular disease, which causes approximately around 3.8 million deaths a year. Scary stuff…
When you consider that we spend 90% of our time indoors, it’s surprising that the focus on air quality is always on the outdoors, when in fact most pollution exposure can also occur when we are inside.
How is air pollution measured?
To give air pollution some statistical context, the quality of the air can be categorised by PM2.5 levels, measured in micrograms per cubic metre (µg/m³). As a general rule of thumb:
0-15 = good (safe) / 16-35 = fairly good / 36-55 = fair / 56-75 = fairly poor / 76+ = poor (harmful)*
The most common air pollutants in the home
We have summarised the finding of multiple studies to give you some insight into the 10 most common indoor air pollution sources… Get ready for some facts!

1. Cooking
Cooking generates nitrogen oxide and particles, which is the same pollutants that you find outdoors – just from a different source. Take on board the fact that kitchens are generally an enclosed area, and the concentration of fumes suddenly increases. A study by Zehnder UK discovered that just cooking an omelette can release more harmful dust than exhaust fumes!
The easiest way to combat cooking fumes is the use of an extractor fan, which sucks in contaminated air and then vents it to the building’s exterior. Teaming this with an Air Purifier captures any additional fumes too – win, win!

2. Cleaning
Many of the products we use at home, contain chemicals called Volatile Organic Compounds (VOCs) which can be emitted as a gas. Products containing VOCs, particularly those in a spray, linger in the air after use and can cause irritation to your lungs. VOCs can be found in washing detergents, furniture polish, carpet cleaners, pesticides and fungicides.

3. Candles and Incense
A scented candle in the home brings warmth and comfort, particularly as the colder months draw in. However, candles and incense sticks emit particles and other pollutants when they burn. Although lighting a candle might produce a lovey smell, it could be contributing to poor indoor air quality.
When candles burn, they produce invisible particles and place particulate matter into the air, which dirties the heating and reduces ventilation in your home. Now we’re not suggesting you throw away your collection of home décor and fragrances, but with incense sticks emitting more than 100 times the amount of fine particles than a candle does, a candle might be the less polluting choice. When choosing your candle, look for beeswax or soy candles as a non-toxic alternative to conventional candle ingredients. Using your candles in well-ventilated, larger spaces can help too.

4. Hair styling
Hair spray seems to be the main culprit here, and although a staple in many a grooming routine, the Zehnder study uncovered some quite alarming findings: When testing the level of PM2.5 after using hairspray one morning (a product that is readily available in high street stores) the study recorded a level of 85 µg/m³, which is over 5 times the safe limit of 15 µg/m³.

5. DIY
Paints, varnishes, and glues can release VOCs, as well as highly toxic chemicals such as formaldehyde. Even months after application, they can continue to release traces of these gases — even though they appear to be fully dried, and the smell is gone. Your best bet is to opt for “low-VOC” paints for your DIY needs, remember to open windows and use an Air Purifier to remove gases as you paint.

6. Damp and Mould
Mould can be caused by leaks and problems which increase moisture levels in the home. The dampness that occurs from mould is associated with higher risks of wheezing, coughing and asthma symptoms. Check your roof, foundation, and basement once a year to catch leaks or moisture problems and reroute any water away from your home’s foundation.

7. Smoking and Vaping
The days of smoking indoors are generally a thing of the past, with the UK’s indoor smoking ban in place since 2007. However, this ban is for public spaces only so smoking in the home is technically still allowed and therefor a personal choice. It’s probably not surprising to learn that tobacco smoke and vaping causes the largest increase in air quality levels, with the Zehnder study reporting a staggering increase of 65,000% (yes sixty five thousand percent) when a smoker lit up a cigarette, jumping the PM2.5 level from 1.3 µg/m³ to 839 µg/m³ over a two-hour period. Considering the average London roadside level is just 23 µg/m³, these figures may make you think twice about allowing smoking inside your own house.

8. Pets
Now we’re not calling our furry friends ‘pollutants’, but unfortunately they can be a huge contributor to the quality of the air you’re breathing. Pet hair, dead skin cells and general pet odour can linger in the air – a particular nightmare for anyone suffering with pet allergies. So, no matter how often you clean your pet, be sure to be cleaning your floors and upholstered furniture at least twice a week, and use an Air Purifier 24/7 to capture any airborne pet particles.

9. Wood burners and Fires
As cosy as they are, it is a fact that wood burners triple the level of harmful pollution particles inside homes when in use. A study by the Atmosphere journal found that wood burners are usually lit for approximately four hours at a time, and when in use, the level of harmful pollution particles inside the home increase threefold. The study found that average particle levels rose to between 27 and 195 µg/m³ when a wood burner or fireplace is burning.

10. Outdoor air pollution can get inside too!
Although open windows and doors can let fresh air in, they can also allow outdoor pollution to enter at the same time – affecting your indoor environment. This includes road traffic, pesticides, construction, and other activities occurring in both rural and urban environments.
Air Purifiers are designed to clean the air and help to remove the pollutants listed above that could be negatively impacting your indoor air quality. Designed to work in the background, Instant Air Purifiers use Advanced 3-in-1 filtration system and plasma ion technology to removes 99.9% of bacteria, viruses, and mould in treated air.¹ With Intelligent Sensors that monitor air quality and adjust fan speed automatically to work 24/7², you can rest assured that whenever your air at home needs cleaning, your Instant Air Purifier will get to work.
Want some more information? Find out more about why you need an Air Purifier.