Development and performance characterization of low, medium and high vacuum primary standards

Three primary vacuum standard systems having the highest metrological qualities in which the pressure is deduced directly from the involved physical quantities uniquely with the proper accuracy and precision, fine resolution and reliability have been developed. This vacuum standardization comprises of a Standard Mercury Manometer for low vacuum, a 4-stage Static Expansion Standard for medium vacuum and an orifice flow type Dynamic Expansion Standard for high vacuum. Each system has explicitly been established and precise measurement model equations with multiple variables are given. The performance of these standards has also been checked discretely with internationally recommended and reliably calibrated secondary standards along with the evaluation of different uncertainties that were found to be within the limits.