How do air barriers contribute to indoor air quality?

Air barriers play a crucial role in enhancing indoor air quality primarily by reducing the infiltration of pollutants and allergens from outside sources. When properly installed, air barriers create a continuous and effective boundary that minimizes the uncontrolled flow of air in and out of a building. This control helps to prevent drafts and air leakage, which can bring in dust, pollen, chemicals, and other irritants that might contribute to poor air quality.

By limiting the unwanted exchange of air, air barriers help maintain a healthier indoor environment. This action is vital in preventing contaminants from entering living and working spaces, thereby supporting better respiratory health and comfort for the occupants. In addition, air barriers can facilitate the effectiveness of mechanical ventilation systems by ensuring that fresh air is brought in from controlled and safe sources rather than from random infiltration points, which may introduce pollutants.

The other options either contribute negatively to indoor air quality or do not relate to it meaningfully. Increased energy consumption, for instance, would not support the goal of maintaining good air quality, while promoting unregulated humidity levels could lead to mold growth and other issues. Similarly, enhancing external air ingress would likely result in increased pollutant infiltration rather than improving indoor conditions.