
8Spectrophotometer NANOCOLOR®Advance 1.0, 08.2020
en
NANOCOLOR®COD 160 REF: 985026
Overview
Thetest iss uitable for thep hot ometric det erminat ionofth ech emi-
cal oxy gen demand(C OD) .Th ete sti sin accor dan cew ith DIN ISO
15705–H45andisequivalenttoEPAStandardMethod5220D.
This test issu itab lefo rwater,was tewa terandsludge.
• Measuringrange:15–160mg/LO2(method0261)
• Num be rof te sts :2 0
• Wavelengthforphotometricdetermination:436/450nm
• Shelfli fe:12mo nth s
• Reactiontime:120minutes
• Storagetemperature:15–25°C
• Storageconditions:protectedfromsunlight,upright.
Method
Theorganiccompoundsofasampleareoxidizedbyheatingthe
sampleinamixtureofsulphuricacidandpotassiumdichromate.
Thechemicaloxygendemand(COD)ofawatersampleisthecon-
centrationofoxygenthatisequivalenttotheamountofpotassium
dichromateconsumed. Thechangeinthepotassiumdichromate
concentration is determined via the change in absorbance after
digestion.
Interferences
Theforeignmaterialsshownheredonotinterferewiththetestup
tot hei ndicatedco nce ntr ati ons (in mg/L).Thec umu lat ive effe cto f
differentinterferingionshasnotbeentested.
Datainmg/L:
• Cl-:1500
Important:Forsamplesinwhichthechloridecontentishigh,shake
thetubetosuspendtheprecipitatepriortoaddingthesample.If
thechloridecontent is greater than 1500 mg/L, you must dilute
Qualitycontrol
Themeasurementofablankvalueandastandardisrecommended
beforeeverymeasuringseriesasqualitycontrolmeasure.
Qualityda ta:
Thefollowingdataweredeterminedduringproductionaccordingto
ISO8466-1andDIN38402-A51:
• Num ber ofLOTs:7 5
• Standarddeviationofthemethod:±1.06mg/LO2
• Coe ffi cie nto fva ria tiono fth epr oce ss: ±1. 28%
• Confidenceinterval:±2.44mg/LO2
Specifieddataforprocedure:
• Sensitivity(absorbanceof0.010Acorrespondsto):2.18mg/L
O2
• Acc uracy ofa mea surem ent val ue:±8 .40 mg/ LO2
LOT-speciccerticatesareavailableatwww.mn-net.com.
Procedure
1. Openroundcellandholdslightlytilted
2. Pipette2mLofsampleintotesttube
3. Sealtesttubeandshakevigorously(usesafetybottle,cuvette
willbecomehot!).
4. Heatfor2hat148°Corfor30minat160°C
5. Takethetubefromtheheatingblock
6. Shakeagainafter10min.whilestillwarm
7. Cool toroomtemperature
8. Cleanoutsideoftesttube
9. Measure
Notes
TestasampleofCOD-freewater(REF918993)togenerateablank
Fig. 6: Test kit instruction
Perform the test according to the instruc-
tions of the respective test kit (Fig. 6). Read
them carefully to obtain accurate and reliable
results. Prepare the sample according to the
instructions.
Note: Clean all cuvettes with a lint-free
cloth before insertion to remove any
impurities or moisture from the cuvette
and to prevent soiling of the cuvette
slot.
Step 5: Run a measurement
NOTICE
Contaminated cuvettes can contaminate the cuvette slot and lead to incorrect
measurement results.
Fig. 7: Measurement of tube tests
Test tubes: Insert the barcoded tube into the
cuvette slot. The barcode is recognized and
the barcode is read automatically (Fig. 7).
For test kits without zero measurement the
result is displayed automatically after a few
seconds.
When using a test kit with zero measurement
the device rst prompts you to measure
the zero solution. The zero measurement is
triggered by pressing . Then the sample
is inserted and the sample is measured by
pressing .
Alternatively, the desired method can be called up by selecting from the lists in the MN-Tests
menu or by entering the test number in the corresponding menu.
Note: The rst time a method is called up, it is automatically started in sub-method 1.
The sub-method (chemical form) can be changed by clicking on the entry
"sub-method" in the result screen.