What is the maximum area of tenant space where corridors can be used for conveying return air?

The maximum area of tenant space where corridors can be used for conveying return air is established to ensure proper air circulation and ventilation while minimizing risks associated with air quality and fire safety. In this case, the guideline specifies that corridors can effectively serve as return air pathways for spaces up to 1,000 square feet. This standard is based on considerations such as the potential accumulation of pollutants, the spread of smoke in the event of a fire, and the overall efficiency of the HVAC system in maintaining comfort levels.

Using corridors as return air ducts can be efficient in smaller spaces, but this upper limit helps to prevent issues that might arise from insufficient airflow and contamination from adjacent areas. Therefore, recognizing that 1,000 square feet is the maximum allowed tenant space for this purpose reflects adherence to safety and engineering principles within the North Carolina Mechanical Code.