A calibration and calculation procedure is suggested in section (10.2.12.2) which is applicable to all total N, P and Si determinations both in manual and flow-analyses. A calibrated analytical setup is required for the respective inorganic component (nitrate, phosphate, silicate).
The desired sample volumes for the determination of total N , P or Si are poured into the oxidation bottles immediately after sampling. If the bottles are closed tightly, the samples may be stored without further precautions. Total Si samples only be stored in plastic bottles.