Uncertainty Analysis of the New Spanish National Pressure Standard

This paper presents the project for developing a new interferometer-based mano-barometer. This system will constitute the National Primary Pressure Standard maintained at CEM. This device is based on the ancient Torricelliʹs experience and applies modern techniques in order to obtain a very accurate instrument. This system will allow the calibration up to 300 kPa with uncertainties about 5-106. Laser interferometry is applied and special attention is given to the accurate determination of fluid density. Hence, this paper describes the technology used in the project. Its influence on the measurement is being studied prior to the manufacturing and assembling phases.