The National Institute of Standards and Technology (NIST) has developed a new transfer standard capable of absolute-mode and differential-mode operation in the range 100 Pa to 130 kPa. This newly built transfer standard relies on resonant silicon gauges (RSGs) of the same type used to provide superior long-term calibration stability in NIST piloted international key comparisons CCM.P-K4 and CCM.P-K5, which covered absolute and differential pressure standards pressures up to 1 kPa (Miiller et al 2002 Metrologia 39 Tech. Suppl. 07001 and 07002). The new transfer standard package differs from the previous packages in that it fully covers the atmospheric pressure range (100 Pa to 130 kPa). This was made possible by the addition of a pair of 130 kPa RSGs to complement a pair of 10 kPa RSGs. The RSG transfer standard package has demonstrated good short-term zero stability and pressure resolution, and has demonstrated long-term instability of only a few ppm at 130 kPa, increasing to 0.01% at 100 Pa. The long-term instability is nominally commensurate with that associated with piston gauge standards, which are limited to pressures of nominally 10 kPa and higher. The main advantage of the new package is that it operates easily at lower pressures than piston gauges while still covering the atmospheric pressure range 100 Pa to 130 kPa.
calibration, key comparisons, metrology, piston gauge, pressure, resonance silicon gauge, RSG, transfer standard, ultrasonic interferometer manometer