IS 8276 : Part 1 : 2025 Method for Calibration of Vacuum Gauges - Part 1 Pressure Reduction by Continuous Flow in the Pressure Range of 10-5 Pa to 10-1 Pa

ICS 23.160

MED 17

1 SCOPE

1.1 This standard (Part 1) specifies a method for the calibration of vacuum gauges in the pressure range of 10-5 Pa to 10-1 Pa, whereby a known low pressure is established by the passage of a known flow of gas through a circular orifice of known conductance.

1.1.1 The upper limit of pressure to which the method is applicable is set by the diameter of the orifice in relation to the mean free path of the gas molecules. The lower limit will depend on the type of gauge being calibrated, and on the amount of sorption or desorption of gas within the apparatus.