• Use pressure of a flow stream to determine volumetric flow measurement.
• A ball within a conical tube floats due to pressure, correlated with gas or liquid flow rate.
• Volumetric flow equals mass flow in standard fluid, temperature, and pressure conditions.
• Calibration to specific gas, temperature, and pressure ensures high accuracy.
• Accuracy decreases with process conditions.
• Alicat mass flow controller can be used for calibrations if labs aren't easily accessible.