The accuracy of the bubble meter method for gas flow measurements

The bubble meter technique is an absolute method of measuring the volume flow rate of gases. It requires accurate standards of mass and time only and is simple in application. This paper describes the method, examines its potential accuracy and derives criteria for design. It is found that errors may be kept below ±1% for flows between 0.1 and 1000 cm 3 sec -1 , while the error may be reduced to ±¼% for flows between 0.1 and 100 cm 3 sec -1 . Modifications to extend these limits are discussed.