How far must air intake openings be located below contaminant sources within 10 feet of the opening?

The correct answer indicates that air intake openings must be positioned at least 3 feet below contaminant sources within a 10-foot radius of the opening. This distance is critical to ensuring that the intake does not draw in contaminants such as dust, fumes, or vapors, which can negatively affect air quality and potentially compromise the health and safety of the environment.

By maintaining a 3-foot separation, air intakes can effectively minimize the risk of pollutants entering the airflow system. This practice is particularly important in order to comply with safety standards and regulations pertaining to air quality in industrial and commercial settings. The specific distance helps ensure that the air being drawn into ventilation or heating systems is as clean and safe as possible, thereby maintaining a healthier indoor environment.

In contrast, smaller distances such as 1 foot or 2 feet would not adequately safeguard against the infiltration of harmful contaminants. A distance of 4 feet could provide an additional buffer, but it is more than what is typically prescribed, making 3 feet the most balanced requirement to ensure safety while also adhering to practical system design.