A low differential pressure standard in the range of 1 Pa to 31 kPa at KRISS

The accurate measurement of differential pressure at low line pressure is important in many industrial and commercial activities. A new differential pressure standard has been developed at the Korea Research Institute of Standards and Science. This standard covers a measuring range of 1 Pa to 31 kPa of differential pressure for operation with line pressures near 100 kPa. As part of its realization, a new automatic weight handling device has been developed, which enables the various weights to be added to or removed easily from the piston without breaking the reference vacuum during measurements. The system can generate differential pressures with an expanded uncertainty of 0.026 Pa + 2.3 x 10(-5)p (k = 2) in the range 1 Pa to 31 kPa.