Indoor air quality is the air quality inside an office, school, home, or another building environment. Sometimes, indoor concentrations of pollutants are 2-5 times higher than outdoor concentrations. People most vulnerable to the effects of air pollution, such as the elderly and people with cardiovascular and respiratory diseases, tend to spend most of their time indoors since many believe that indoor air quality is better than outdoors.
In recent decades, indoor air quality has decreased due to an increase in the use of synthetic building materials, furnishings, pesticides for indoor plants, personal care products, and household surface cleaners.
Poor indoor air quality can have a range of different health effects on a person. They include:
1. Irritation of the throat, nose, and eyes.
2. Fatigue, dizziness, and headaches.
3. Cancer, heart disease, and respiratory disease.
Researchers and experts have studied and established the links between indoor air pollutants and health effects. Some of them are:
1. Carbon monoxide is a toxic gas. Even short-term exposure to high levels of carbon monoxide in an indoor environment can be lethal.
2. Buildings with poorly maintained air conditioning or heating systems often host the bacterium Legionella. The bacterium is the cause of Legionnaires’ disease, a form of pneumonia, in humans.
3. Mold, dust mites, tobacco smoke, particulate matter, and others trigger asthma attacks. Some asthmatics may experience asthma attacks following exposure to these pollutants.
Ongoing research investigates the link between poor indoor air quality and issues like productivity in an occupational setting and student performance in a classroom. Another research area currently under evolution is ‘green building’ design, construction, operation, and maintenance. The idea is to achieve energy efficiency and enhance indoor air quality.
Sources of Indoor Air Pollution
Most pollutants affecting indoor air quality come from sources located inside the building. However, some pollutants may originate outdoors. The common pollutants causing poor indoor air quality include:
1. Byproducts of combustion such as carbon monoxide, tobacco smoke, and particulate matter
2. Radon, pet dander (pet fur or hair that strays), and mould that occurs naturally
3. Asbestos, lead, and pesticides used for indoor plants
4. Ozone from some air cleaners
5. Volatile organic compounds from various products such as cleaners.
The indoor sources affecting indoor air quality include:
1. Combustion Sources
These include tobacco, cooking appliances, wood, coal heating, and fireplaces. All these sources release harmful byproducts of combustion, such as carbon monoxide and particulate matter, into the home.
2. Household Products
Cleaning supplies, insecticides, paints, and other products introduce volatile organic compounds and various chemicals into the indoor environment.
3. Building Materials
Asbestos fibres and chemical off-gassing from pressed wood products are also potential sources of indoor air pollution. There are also many naturally occurring indoor pollutants, such as mould, pet dander, and radon.
Apart from indoor sources, even pollutants originating outdoors can affect the air quality inside your home, office, or classroom. The outdoor pollutants can enter buildings through open windows and doors, cracks in structures, and ventilation systems. Some pollutants can enter a building through its foundation. For example, radon occurs naturally as uranium in rocks and soil decay. Gaps or cracks in the structure of the building provide a passageway for radon to enter an indoor environment. Other outdoor sources that affect indoor air quality are:
1. Harmful smoke blown out by chimneys can re-enter homes and reduce indoor air quality.
2. Volatile chemicals in water supplies can enter your home when you use water for cooking or taking a shower.
3. When you enter a building, you can bring in pollutants via the soil on your shoes and dust on your clothes. A few pollutants adhere to soil and dust particles.
In addition to indoor and outdoor sources, several other factors can affect indoor air quality. The air exchange rate between the indoors and outdoors is one of them. Building design, construction, and operating parameters affect the air exchange rate. The air exchange rate is ultimately a function of infiltration (air flowing in through joints, opening, cracks in walls, ceilings, floors, or around windows and doors), natural ventilation (air flowing in through open windows and doors), and mechanical ventilation (air forced inside or outside a building by fans or air handling systems).
To minimize air pollution inside your home and boost indoor air quality, follow these simple practices:
1. Keep your windows open
Adequate ventilation all day long promotes indoor air quality. Opening windows is a great way of encouraging the exchange between indoor and outdoor air. This way, the air will carry all the pollutants inside your home outdoors.
2. Do not allow smoking inside
Ban smoking inside your home. According to the Environmental Protection Agency, passive smoking, breathing in the smoke from someone else, accounts for 3,000 lung cancer deaths every year among non-smokers. If you’re at an event or a restaurant, politely ask someone smoking not to do so. Alternatively, you could only visit restaurants that do not allow people to smoke on the premises.
3. Give your pets a bath
Washing and bathing pets and their bedding regularly minimizes allergy-causing dander. Do not let your pets enter your bedroom.
4. Use exhaust fans
Run exhaust fans in kitchens while cooking. The fan will rid your home of cooking fumes.
5. Put down a doormat
Put down a doormat in front of the main entrance of your home. Wiping shoes before someone enters your home will reduce the number of pollutants they carry into the house. If possible, establish a no-shoes policy inside your house.
6. Avoid covering up odors
Using air fresheners, incense, and scented candles might rid your home of odors, but researchers have found that they trigger asthma.
7. Skip Lighting Fires
A fireplace looks delightful and cozy, with flames dancing around. But they release soot and smoke into your home. Use your fireplace rarely or on very special occasions.
8. Minimize carpeting
Carpets on the floor trap pollutants like dust mites, mold spores, pet dander, and dust and dirt. Choose hard-surface flooring instead of a carpeted floor.
9. Store chemicals safely
Store your pesticides, glues, surface cleaners, and other solvents away from living areas. Better yet, try making your own household surface cleaners like bio enzymes and a mixture of white vinegar and water.
10. Clean filters
Make sure you regularly clean the filters of your air conditioners. The filters trap dust. They could introduce dust into your indoor air if not cleaned properly.