A trend of measurements of high pressure with an accuracy of better than ±0. 1% in the range up to 1 GPa is described. The instruments used are the dead - weight piston manometer, the manganin resistance manometer and strain - gauge type pressure transducer. The piston manometers are available commertially with an accuracy of ±0. 01 %. The secondary instruments should be calibrated against the primary but have become very convenient to use due to the progress of the digital electronic indicator.
