What is the minimum vertical distance for air intake openings above streets and alleys?

The minimum vertical distance for air intake openings above streets and alleys is 25 feet. This requirement is established to ensure that the air entering a building’s mechanical system is clean and free from contaminants that may arise from traffic or other outdoor sources. By maintaining a height of 25 feet, the intake openings are positioned safely above typical vehicular emissions and other potential pollutants present at street level, which contributes to enhancing indoor air quality.

This specification appears to be carefully designed, considering the typical height of vehicles and the distribution of air pollutants in urban settings. When air intakes are situated at adequate heights, it minimizes the risk of drawing in harmful particulates or noxious fumes that can negatively impact the health and comfort of the occupants inside the building. Additionally, adhering to this height helps ensure compliance with relevant safety and engineering standards outlined in the International Mechanical Code (IMC).