Clean indoor air is achieved through:

• Good ventilation
  • Using a household heat exchanger where needed, to preserve the heat or coolness of the air, without
  • Good thermal mass (part of passive solar design allows more ventilation while maintaining a comfortable temperature.
• Not using indoor fires. Or if one is used:
  • Ensure the stove or cooker is properly sealed, allowing air in with no leaks allowing smoke out. There should be noticeable suction where air is pulled into the fire, to avoid smoke coming out.
  • Ensuring proper burning within the device, so that any flue that does escape is fully burnt, minimizing dangerous carbon monoxide^W and airborne particulates^W.
  • Ensuring especially good ventilation (challenging when the fire is for keeping warm in winter).
  • Don't use more than necessary - wear extra clothing, and keep active - an extra reason to do exercise.
• Minimizing the use of chemical cleaners^W (particularly those with volatile organic chemicals^W). If they are needed, do it in good weather where you can keep windows and doors open for several hours.
• Indoor plants - what are the factors that make these effective?^{[expansion needed]} Particular varieties?
• Avoid the various other sources of indoor air pollution.