ASTM D7058 Standard Test Method for Determination of the Red Dye Concentration and Estimation of Saybolt Color of Aviation Turbine Fuels and Kerosine Using a Portable Visible Spectrophotometer
8. Sampling
8.1 Samples shall be taken in accordance with Practice D4057 or D4177.
8.2 Precautions shall be taken to shield the samples from light prior to analysis.
9. Calibration and Standardization of the Apparatus
9.1 Calibrate the instrument according to the procedure described in Annex A2.
NOTE 1 - The instruments are calibrated at the factory by the vendor.
9.2 Qualify the instrument according to the procedure described in Annex A3.
NOTE 2 - The instruments are qualified at the factory by the vendor.
9.2.1 If the qualification procedure is performed by the vendor, then the user shall perform a quality control check according to the procedure described in Section 10.
10. Quality Control Checks
10.1 To confirm the performance of the instrument periodically, measure the red dye concentration and the estimated Saybolt color of three control samples using the procedure outlined in Section 11. The quality control check standards shall be analyzed at least once a week or before the sample analysis if the instrument is used less frequently than weekly or if the instrument is moved to a different laboratory or field location.
