Indoor Air Quality (IAQ)
Quality of air inside buildings is represented by:
- Concentration of pollutants; and
- Thermal (Temperature & Relative Humidity) conditions
People spend 80-90% of their time indoors. Indoor air quality is linked to health, comfort, and performance of the occupants.
Effects of Enclosed Space
- Decrease in Oxygen level or Increase in CO2 level
- Increase in temperature and humidity (Dampness)
- Increase in bio-aerosol and odour
- Accumulation of air pollutants
Indoor Air Pollution – A Global Concern Area
- India: Indoor air pollution is one of the top 10 death, disease risk factors
- Ranked among top 5 environmental health risks to public by Environmental Protection Agency
- Carbon based gaseous pollutants (VOCs) indoors could be 2 to 5 times higher than outdoors
Sources of Indoor Air Pollutants
- Fuel-burning combustion appliances
- Tobacco products
- Building materials and furnishings
- Products for household cleaning and maintenance, personal care, or hobbies
- Central heating and cooling systems and humidification devices
- Excess moisture
- Outdoor sources such as Pesticides / Outdoor air pollution
- Pollutants include NO2, CO, VOC, CO2, RSPM (PM10 / PM2.5), SO2, O3, Formaldehyde, Pesticides, Asbestos, etc.
Harmful Effects of Indoor Air Problem – Sick Building Syndrome
Building occupants experience acute health and comfort effects which are linked to time spent in the building, but no specific cause of illness identified. Not a clinically diagnosable disease.
- Short-Term Effects: Some health effects may show up shortly after a single exposure or repeated exposures to a pollutant. These include irritation of the eyes, nose, and throat, headaches, dizziness, fatigue, Dry or Itchy skin, nausea, difficulty in concentration, symptoms of some diseases such as asthma may show up, be aggravated or worsened.
- Long-Term Effects: These include some respiratory diseases, heart disease and cancer.
7 Strategies to improve Indoor Air Quality
1. Source Control:
Most effective way to improve IAQ is to eliminate individual sources of pollution or to reduce their emissions. Avoid smoking indoor or in office premises, choose low VOC-emitting products and control car exhausts in the office premises.
2. Improved Ventilation:
Ventilation and shading can help control indoor temperatures. Ventilation also helps remove or dilute indoor airborne pollutants coming from indoor sources. Open doors and windows, when temperature and humidity levels permit. However, be mindful of outdoor allergens during spring and fall seasons.
3. Control Moisture / Dampness:
Control relative humidity levels to less than 60percent, using dehumidifiers. Clean humidifiers frequently. If mold grows on any porous materials like dry wall, ceiling tiles or wood, discard and replace. Damp is a silent killer. Sources include Seepage / Leakage / Quality of Construction / Improper finishing of homes, offices, properties.
4. Use Indoor Plants:
Indoor Plants can improve indoor air quality by filtering carbon dioxide; There are plants which are easy to maintain, emit oxygen continuously, and do not need soil – can be grown in glass water bottles (e.g, Money Plant, Sansevieria / Snake Plants, etc). The Snake Plant cleans air better than most other indoor plants as it has the ability to absorb excessive amounts of carbon monoxide. Additionally, it emits oxygen and filters other toxins from the air such as benzene, xylene, trichloroethylene and formaldehyde. Money plant energizes the home by filtering air and increasing oxygen inflow.
5. Air Cleaners:
Effectiveness of an air cleaner depends on how well it collects pollutants from indoor air and how much air it draws through the cleaning or filtering element.
6. Maintain maximum cleanliness in your premises:
Keep your premises clean. Clean furniture / equipment on a weekly basis to reduce exposure to allergens, including dust mites. Place walk-off mats / carpets & vacuum cleaners with disposable bags and microfiber cloths.
7. Maintain Air-conditioning / HVAC System:
Make sure that fuel burning furnaces, fireplaces, heaters, range tops, exhaust fans and other appliances are vented to the outside well away from windows and heating ventilation and air-conditioning(HVAC) intakes.