ORBECO SP600, Instruction Manual, Page: 94 / 334

92 SP600 Spectrophotometer 01/2008
1.1 Methods
COD MR
with Tube Test
0 – 1 500 mg/l O
2
1. Open one white capped reaction vial and add 2 ml
deionized water (this is the blank (Note 1)).
2. Open another white capped reaction vial and add
2 ml of water sample (this is the sample).
3. Close the vials with the cap tightly. Invert the vial gently
several times to mix the contents.
(CAUTION: The vial will become hot during mixing!)
4. Heat the vials for 120 minutes in the preheated reactor at
a temperature of 150°C .
5.
(CAUTION: The vials are hot!)
Remove the tubes from the heating block and allow them
to cool to 60°C or less. Mix the contents by carefully
inverting each tube several times while still warm.
Then allow the tubes to cool to ambient temperature
before measuring. (Note 2).
6. Place the vial (the blank (Note 3, 4)) in the sample
chamber making sure that the marks are aligned.
7. Press
ZERO
key.
8. Remove the vial from the sample chamber.
9. Place the vial (the sample (Note 3, 4)) in the sample
chamber making sure that the marks are aligned.
10. Press TEST key.
The result is shown in the display in mg/l COD.
Zero accepted
prepare Test
press TEST
prepare Zero
press ZERO
Ø 16 mm
1 3 1