How does ventilation rate affect indoor air quality in offices and industrial buildings?

Ventilation rate plays a central role in indoor air quality because it controls how quickly stale or contaminated air is replaced with fresh air. In simple terms, the higher the ventilation rate, the more diluted airborne pollutants become. In offices, inadequate ventilation often leads to elevated carbon dioxide levels, which can cause drowsiness, headaches, and poor concentration. While CO2 itself isn’t usually harmful at these levels, it’s a good indicator that fresh air supply may be insufficient.

In industrial buildings, ventilation becomes even more critical. Processes may generate dusts, fumes, or vapours that need to be removed before they build up to harmful concentrations. If ventilation rates are too low, these contaminants can linger in breathing zones, increasing exposure risks.

That said, more ventilation isn’t always better. Poorly balanced systems can create draughts, uneven temperatures, or energy waste. The goal is appropriate ventilation for the space, occupancy, and activities taking place, not just maximum airflow. When ventilation rates are properly designed and maintained, indoor air quality is generally more stable and predictable.