Indoor air quality is a global challenge and has been consistently brewing conversations and concerns. People understand the need to avoid busy roads, turn off idling engines and protect the outdoor environment from pollutants. But the actual knowledge about the impact that air quality has on individuals is scarce, and that's not only during the comparatively short periods of time we spend outside, but indoors where people spend 90% of the time.

Before taking preventive steps toward air pollution, it is important to understand the air quality that we are exposed to, be it indoor or outdoor. On the occasion of Clean Air Day 2022, which is celebrated on September 7 every year, Dyson Engineer Muzaffar Izamuddin, from the Environmental Care at Dyson, has answered some important questions that could help to make educated decisions to reduce air pollution exposure. 

New Delhi pollution
A blanket of toxic haze engulfs the national capital.IANS

Q. Can air pollution be invisible?

Yes, but air pollution seems to grab attention when we see smog or haze. We often forget that visible pollution is not the only form of harmful pollution and that invisible air pollution such as nitrogen oxides can exist all year round and can be more or equally deadly.

Q. If there is outdoor pollution outside, is it better to stay indoors?

Home isn't always a safe haven and indoor air pollution can be worse than outdoors. Pollution can be generated indoors through day-to-day activities, enter the house from outside, emit from surfaces and eventually make up a complex cocktail of pollutants. As we increasingly seal our homes to seemingly shut pollution out, in truth, we are maybe shutting it in.

Every day we can breathe in up to 9,000 litres of air1 and spend up to 90% of our time behind closed doors2. Daily household activities such as VOCs (volatile organic compounds) released from using cleaning solvents, deodorants and scented candles are some of the more common indoor air pollutants. Other major indoor air pollutants include gases from cooking and central heating, mould, allergens, pollen and pet dander, or formaldehyde from mass-produced furniture. Whether we are at home or in office, we could be breathing potentially harmful air. Having an air purifier with both HEPA and activated carbon filter to capture both pollutant particles and toxic gases can help improve the air quality inside your homes to great extent.

Air pollution, BS-IV, emission

Q. Which is more harmful - indoor pollution or outdoor pollution?

Indoor and outdoor air pollution are often treated as two separate entities but outdoor pollutants, such as vehicle exhaust fumes, pollen and mould spores, can also enter our indoor spaces. Once inside, they can react with indoor pollutants, creating a complex cocktail of dirty air. Likewise, indoor pollutants, such as smoke from burning wood or cooking fumes, can exit buildings through ventilation. This continuum blurs distinctions between indoor and outdoor pollutants but with the right knowledge, we can take simple measures to prevent toxic air from building up inside the homes. For instance: we can control our indoor air with an air purifier.

Dyson air purifier

Q. Is pollution a seasonal problem?

It is a 365-day issue! Different seasons see an increase in certain pollutants due to various factors such as temperature, climate, and human activities. Worsening air quality is a global problem, and India is one of the largely impacted countries. As per the World Health Organisation (WHO), India has 37 of the world's 50 most polluted cities3, throwing light on the much-ignored issue of air pollution and the need to catalyse clean air in the country all year round.

Q. How does air quality impact our lives?

Air quality is a complex issue, and the impact depends on multiple factors, including but not limited to age, location, health, how active one is and length of exposure time. To name just a few!

At Dyson, we spend a lot of time researching the impact of indoor air pollution. Every day we can breathe in up to 9,000 litres of air and spend up to 90% of our time behind closed doors and that's even before lockdown. Whilst the specific medical impact of indoor air pollution continues to be researched, we know that exposure time is a very important factor, and therefore indoor air quality, logically, impacts us the most because our length of exposure time is higher.

Air Pollution New Delhi
Vendors selling drinks stand beside vehicles near the India Gate war memorial on a smoggy day in New Delhi February 1, 2013.Reuters

Q. What is AQI/Air Quality Index and why should I care about AQI rankings?

The Air Quality Index (AQI) is an index for reporting air quality on a daily basis. It is a measure of how air pollution affects one's health within a short time period. The purpose of the AQI is to help people know how the local air quality impacts their health. A yardstick that runs from 0 to 500; the higher the AQI value, the greater the level of air pollution and the greater the health concerns. The concept of AQI has been widely used in many developed countries over the last three decades. AQI quickly disseminates air quality information in real time.

Q. What are some tips to ensure healthy AQI?

We can do little to control the quality of the air we breathe outside. But we can follow these tips to try and keep your home free of pollution.

Use cleaning products wisely: Some of the VOCs found in our homes can come from the chemicals in cleaning products we use on kitchen surfaces, bathrooms and windows. Using natural cleaning products can help lower the amount of VOCs in your indoor air.

Vacuum regularly: When you dust your sofa or play with a cushion, one might see a burst of dust in the air. This dust can stay in the air indoors and be breathed in, however, regular vacuuming is one of the easiest ways to reduce particulate pollution at home.

Scents in moderation: Some of the things we might enjoy at home, like scented candles, can also be sources of indoor air pollution. Rather than completely letting go of lighting candles, try them in moderation and preferably in the evening.

Be careful when letting in "fresh air": If you reside close to a high traffic area or a busy road, opening the window can allow outdoor pollution, gases like nitrogen dioxide and sulphur dioxide, into your home.

Ensure ventilation while cooking: Frying with oil can create particulate pollution and using a gas stove can also create gaseous pollutants like NO2. When cooking, try to ensure that kitchen appliances are vented outdoors, open windows if the air outdoors is clean enough to encourage polluted air to flow out, or use mechanical ventilation like a purifying fan which can assist by filtering out pollutants.

Use an air purifier: A good air purifier should not only be able to capture allergens and pollutants as small as PM0.1 but also should be able to filter out harmful gases like VOCs, NO2, etc. to purify the whole room.