Nate Core Practice Test 2025 - Free Practice Questions and Study Guide

A ventilation system primarily functions by introducing fresh air into a space while exhausting stale air, which is crucial for maintaining indoor air quality. The fresh air helps to dilute and remove indoor pollutants and ensures that the oxygen levels are sufficient for the occupants. This process aids in preventing issues related to poor air quality, such as the buildup of carbon dioxide, which can occur in tightly sealed spaces.

While filtering air pollutants is an important aspect of some ventilation systems, it does not encompass the core function of providing fresh air and removing stale air. Heating or cooling air before it enters living spaces is also significant, but these processes are typically part of the HVAC (heating, ventilation, and air conditioning) system and do not capture the primary role of ventilation itself, which is focused on air exchange. Thus, the primary function of a ventilation system is best represented by the introduction of fresh air and exhaust of stale air to maintain overall indoor air quality.