Precautions for Calibration of the VN3100 Portable Turbidimeter

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Calibration of the VN3100 Portable Turbidimeter is of great importance, as it directly determines the accuracy of measurement results. The precautions for calibration are as follows:

1. Shake the required standard solutions thoroughly (for 2–3 minutes).

2. Let the well-shaken standard solutions stand for 5 minutes.

3. Thoroughly clean, rinse and dry the outer walls of the reagent bottles.

4. Before using all standard solutions, quickly apply a layer of silicone oil to the outer walls of the vials.

5. Perform the calibration procedure.