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Constant pressure primary flow standard for gas flows from 0.01 cm3/min to 100 cm3/min (10-8 mol/s to 10-5 mol/s)



Robert F. Berg, Gooding Timothy, Robert E. Vest


We describe a flow meter for gas flows in the range from 0.01 sccm to 100 sccm with a relative standard uncertainty of 0.03 % at 1 sccm. (1 sccm ≈ 1 cm3/min of an ideal gas at 101325 Pa and 0 C ≈ 0.7 mol/s.) The flow meter calibrates a secondary meter by withdrawing a piston from a cylinder held at constant pressure P while gas flows from the secondary meter into the cylinder. The flow meter can operate anywhere in the range 10 kPa
Flow Measurement and Instrumentation


constant pressure flow meter, gas flow, primary gas flow standard


Berg, R. , Timothy, G. and Vest, R. (2013), Constant pressure primary flow standard for gas flows from 0.01 cm<sup>3</sup>/min to 100 cm<sup>3</sup>/min (10<sup>-8</sup> mol/s to 10<sup>-5</sup> mol/s), Flow Measurement and Instrumentation, [online], (Accessed April 14, 2024)
Created December 17, 2013, Updated November 10, 2018