What is the key reason for maintaining a suitable flow rate when using air sampling pumps?

Maintaining a suitable flow rate when using air sampling pumps is crucial to ensure an accurate representation of air concentrations. The flow rate determines how much air is drawn through the sampling media over a specific period, which directly correlates with the concentration of contaminants present in the air. If the flow rate is too high or too low, it can lead to inaccuracies in the measurements obtained. For example, a flow rate that is too high might miss capturing some larger particles, while one that is too low could result in saturation of the sampling media and inaccuracies in calculating the atmospheric concentration of airborne substances. Properly setting and maintaining the flow rate allows for reliable and valid data collection, which is essential for assessing exposure levels and ensuring compliance with safety regulations.