Measurement of gas flow rate from helium standard leaks

Helium standard leaks are widely used to check and calibrate mass spectrometer leak detectors. Precisely known gas flows are required for measurement of quantities of standard leak rates. A fundamental task of the constructed and presented calibration apparatus is precise measurement of gas leak rate. Thus a primary standard for calibration helium standard leaks in the range from 10−10 to 10−5 Pa m3/s has been completed at the Laboratory of Vacuum Measurements in Tele & Radio Research Institute.

► The paper presents newly developed and completed primary standard system for helium standard leaks calibration.
► The accumulation-dump method is applied.
► Quadrupole mass spectrometer is used for helium pressure measurements.
► The primary standard system is used for calibration in helium flow in the range of 10−10–10−5 Pa m3/s.