What is a key characteristic of slight positive pressurization?

A key characteristic of slight positive pressurization involves creating a situation where the air pressure inside a building is slightly higher than the outdoor ambient air pressure. This condition typically arises when more air is introduced into the space than is allowed to escape, which aligns with the concept of some air being made up while most is returned. In practice, slight positive pressurization can help prevent the infiltration of outdoor contaminants, aiding in indoor air quality management and mold prevention. It shows an active control of airflow, ensuring that while there may be some air being exhausted or allowed to return, the focus is on maintaining a slight positive pressure by introducing fresh air.

In contrast, other options describe conditions that do not align with the principles of slight positive pressurization. For example, exhausting all air out of the building indicates negative pressure, while excessive moisture buildup is typically a concern in negative pressure situations where outdoor air cannot adequately flow in to balance humidity levels. Lastly, preventing air from entering the building suggests an entirely sealed environment, which contradicts the concept of introducing enough air to maintain positive pressure.