Which of the following refers to ventilation that allows outside air into a building?

Outdoor air ventilation specifically refers to the process of introducing outside air into a building to ensure good indoor air quality. This method is essential for diluting indoor pollutants and providing fresh air to occupants, which is a key aspect of sustainable building practices and is emphasized in LEED certification criteria.

In contrast, local exhaust refers to systems that remove contaminated air from specific areas within a building, rather than bringing in fresh outdoor air. A heating and cooling distribution system regulates temperature but does not inherently bring in fresh air from outside; it circulates the conditioned air that has already been processed. Air infiltration involves uncontrolled leakage of outside air into a building through cracks and openings, which is not a designed method of ventilation and can lead to energy inefficiencies.

Thus, outdoor air ventilation is the accurate term for the controlled process of allowing fresh outside air into a building, fostering a healthier indoor environment.