What instrument is used to calibrate the flow rate of a pump in asbestos monitoring?

The instrument used to calibrate the flow rate of a pump in asbestos monitoring is indeed a rotameter. A rotameter measures the flow of liquids or gases in a circular tube and allows for a visual indication of the flow rate. As the fluid passes through the rotameter, it lifts a float, and the height of that float correlates with the flow rate. This makes it particularly useful in ensuring that pumps used for asbestos sampling are delivering the correct volume of air at the right rate, which is crucial for accurate monitoring and compliance with safety regulations.

Using a rotameter in asbestos monitoring provides precise control and helps ensure that air samples reflect the true conditions in the environment. This is essential for making informed decisions regarding worker safety and environmental health. Other instruments mentioned, while they have their specific uses, do not focus on directly measuring or calibrating flow in the same way a rotameter does. For instance, a flowmeter could measure flow but often does not offer the level of precision and direct visual feedback that a rotameter provides.