Indoor air quality (IAQ) refers to the quality of the air within and around buildings and structures, especially as it relates to the health and comfort of occupants. Good indoor air quality is essential for maintaining a healthy and productive indoor environment, while poor indoor air quality can lead to various health issues and discomfort.

Several factors contribute to indoor air quality:

1. Air Pollutants: Indoor air can contain pollutants such as dust, pollen, mold spores, pet dander, volatile organic compounds (VOCs) from cleaning products and building materials, tobacco smoke, and gases like carbon monoxide and radon.
2. Ventilation: Proper ventilation is crucial for maintaining good indoor air quality. Ventilation systems bring in fresh outdoor air and remove stale indoor air, diluting pollutants and maintaining oxygen levels. Inadequate ventilation can lead to the buildup of indoor pollutants.
3. Humidity Levels: Relative humidity levels should ideally be maintained between 30% and 60% to prevent mold growth, dust mites, and other moisture-related issues. High humidity can promote mold and mildew growth, while low humidity can cause discomfort and respiratory problems.
4. Temperature: Indoor temperature affects comfort levels and can influence IAQ indirectly. Higher temperatures can increase the concentration of some indoor pollutants and contribute to discomfort, while lower temperatures can affect moisture levels and promote mold growth.
5. Air Filtration: Air filtration systems can remove particles and pollutants from indoor air, improving air quality. High-efficiency particulate air (HEPA) filters are effective at capturing small particles, while other filtration technologies target specific pollutants like VOCs.
6. Source Control: Preventing or minimizing the use of products and materials that emit pollutants can help improve indoor air quality. This includes using low-VOC paints and building materials, choosing environmentally friendly cleaning products, and avoiding smoking indoors.
7. Regular Maintenance: Regular cleaning and maintenance of HVAC systems, air ducts, and ventilation systems are essential for preventing the buildup of dust, mold, and other contaminants. Changing filters, cleaning ducts, and ensuring proper airflow can help maintain good indoor air quality.

Poor indoor air quality can lead to a range of health problems, including respiratory issues, allergies, asthma, headaches, fatigue, and irritation of the eyes, nose, and throat. In severe cases, it can contribute to more serious health conditions.

Monitoring and improving indoor air quality is important for ensuring the health and well-being of building occupants. Strategies such as proper ventilation, air filtration, humidity control, and source control can help create a healthier indoor environment.