Intake openings shall be located not less than 3 feet below contaminant sources where such sources are located within _____ of the opening.

The requirement for intake openings to be located not less than 3 feet below contaminant sources when such sources are located within 10 feet of the opening is based on safety and efficiency in HVAC design. The intent of this regulation is to prevent contamination of the air being drawn into the system.

When intake openings are positioned too close to potential contaminant sources, including exhausts or vents from appliances, there is a higher risk of drawing in pollutants, which can affect air quality and system performance. By establishing a minimum vertical distance of 3 feet below these sources, it helps to ensure that any contaminants will disperse sufficiently before they can be drawn into the HVAC system.

This practice is critical for maintaining healthy indoor air quality and ensuring the efficiency of HVAC operations. The specific distance of 10 feet sets a practical standard that balances safety with the feasibility of installation and operation in various building configurations.