BERYLLIUM and compounds, as Be: METHOD 7102, Issue 2, dated 15 August 1994 - Page 3 of 3 CALIBRATION AND QUALITY CONTROL: 9. Calibrate daily with at least six working standards over the range 0.005 to 1 µg Be per sample. a. Use serial dilutions of known amounts of calibration stock solution in 2% Na 2SO 4/ 3% H 2SO 4 to prepare working standards.