What does capture velocity refer to in ventilation systems?

Capture velocity is a critical concept in the design and operation of ventilation systems, particularly in applications such as industrial workplaces where airborne contaminants may be present. It refers specifically to the minimum velocity of air required to effectively draw airborne contaminants into a capture device, such as a hood or exhaust system. This velocity is crucial for ensuring that the contaminants do not escape into the work environment, thus protecting worker health and safety.

Understanding this concept is vital for engineers and safety professionals, as they must ensure that the ventilation systems they design or implement maintain adequate capture velocities to control and mitigate exposure to hazardous substances. Each workspace and type of contaminant may require a different capture velocity, which is usually determined by factors such as the type of contaminant, its size, and its density.

In this context, the other options do not accurately describe capture velocity. They may address aspects of airflow or contamination detection, but do not specifically relate to the essential function of capturing contaminants at the source through appropriate air movement.