In what condition must mechanical ventilation systems for parking garages operate?

Mechanical ventilation systems in parking garages must operate "always clear of obstructions" to ensure safe and effective airflow. It is critical that these systems remain unobstructed to facilitate the removal of vehicle emissions, prevent the buildup of harmful gases, and maintain a healthy environment for occupants and emergency responders. Obstructions can hinder airflow, leading to inadequate ventilation, which drastically increases the risk of hazardous conditions.

While other conditions, such as operating only when occupied, intermittently as needed, or continuously, may seem practical in varying contexts, they do not address the foundational safety requirement of ensuring unobstructed airflow. Keeping ventilation systems free from obstruction is essential for maintaining air quality and ventilation efficiency in a space that can experience high concentrations of pollutants from vehicle exhaust. Maintaining this clarity is fundamental to the design and operation of such systems in parking garages.