Water analysis test kit COD

The reaction time must be respected to get a right measurement. It depends on the temperature of the sample. After the specified time, compare the color of the tube with the standard colors. The nearest color indicates the chemical oxygen demand of the sample. A color between two standard colors indicates a value between the two standard values. (1) Remove the line to clear the aperture from the top of the tube. (2) Press the sides of the tube to expel approximately half of volume. Maintain pressed. (3) Immerse the tube in the sample. Release the sides to fill the tube up to the half. Shake the tube a few times.(4) After the reaction time (see back ofthe page), put the tube on the color chart as shown and compare with the standard colors.