RETESTING OF STATE STANDARD SAMPLES OF SOIL MASSES

A reliable way to ensure the validity of analytical information is to create standard samples, test them in interlaboratory experiments, and use them widely for controls and calibration in analytical practice. Results are examined by the testing, retesting, and additional testing of three well-known standard soil samples: Kursk Chernozem SP-1, Mosc ow Sod-Podzolic soil SP-2, Caspian Light Chestnut soil SP-3. The sampl es are recorded with the State Register of Measures and Measurement In struments as 901-90, 902-90, and 903-90, respectively, with a period o f application until the year 2000.