Instruction Manual
Dear Customer,
Thank you for choosing a Hanna product. Please read this
instruction manual carefully before using the reagent. This
manual will provide you with the necessary information for
the correct use of the reagents. If you need additional
information, do not hesitate to mail us at
Remove the product from the packing material and examine
it carefully to make sure that no damage has occurred during
shipment. If there is any damage, notify your Dealer.
Each kit is supplied complete with:
•COD test tubes (25 pcs);
•Instruction Manual.
Note: save all packing material, any defective item must be
returned in its original packing.
Two reagent kits are available, according to different ISO COD
ranges:
•HI 93754F-25 LR: COD - ISO Reagent LR
•HI 93754G-25 MR: COD - ISO Reagent MR
Each kit contains 25 ready-to-use vials with premeasured
reagents: just add sample to the vial and tightly cap it before
digestion.
Reagents are in accordance with ISO 15705:2002 method.
This method covers the determination of COD in surface water,
domestic and industrial wastes.
The sample is digested in the presence of dichromate at
150 °C for 2 hours. Oxidizable compounds reduce the
dichromate (orange) ion to the chromic (green) ion.
Before starting to use these reagent kits it is
important to read carefully this manual and the
Health & Safety Data Sheet (HSDS). Pay
particular attention to all warnings, cautions, and notes.
Failure to do so may result in serious injury to the operator.
1. Thoroughly shake and homogenize the sample. If
necessary, use a blender.
2. For sample digestion use a block heater reactor with holes
to accommodate digestion vials. Use always the safety
shield.
Preheat the reactor to 150 °C (302 °F). For correct use of
the reactor follow Reactor Instruction Manual*.
Do not use an oven or microwave because leaking samples
can generate a corrosive and possibly explosive
atmosphere.
3. Remove the cap from a reagent vial for the required COD
range.
Note: the reagent is light sensitive, thus store the unused
vials in their container and in a refrigerator if possible.
4. Using a Class A glass pipette, add 2 ml of sample to a
HI 93754F-25 vial for low range or to a HI 93754G-25
vial for medium range, while keeping the vial at a 45-
degree angle.
This is the sample.
5. Replace the cap tightly and
mix by inverting the vial a
couple of times.
Warning: as the vial
becomes very hot
during mixing, be
careful in handling it.
6. Using another clean Class A glass pipette, add 2 ml of
deionized water to another HI 93754F-25 vial for low
range or to a HI 93754G-25 vial for medium range, while
keeping the vial at a 45-degree angle, repeating steps 4
and 5. This is the blank.
Note: for an accurate measurement, run a blank with each
set of samples and use the same box of reagents for blank
and samples.
7. Wipe the outside of the
vials with the HI 731318
or a lint-free cloth and
insert the vials into the pre-
heated reactor*.
8. Heat the vials at 150 °C for
2 hours ± 10 minutes.
9. At the end of the digestion
period, turn the reactor off.
Remove the vials from the
block heater.
Warning: as the vials
are very hot, be
careful in handling
them.
10. Place the vials in the
HI 740216 rack and allow
to cool to 60 °C or less.
11. Mix the contents by carefully inverting
each vial several times while still
warm. Then allow the vials to cool to
ambient temperature before
performing the measurement.
12. For colorimetric determination of COD, follow the procedure
described in the Photometer Instruction Manual*.
* Note:for best results in readings use the Hanna equipment:
C9800 Reactor and C99 or C214 Photometers.
INTERFERENCES:
chlorides >1000 mg/L (ppm)
Samples with higher chloride concentration should be diluted.
The chemicals contained in these kits may be
hazardous if improperly handled. Read the
Health & Safety Data Sheet before performing
tests.
Safety equipment: Wear suitable eye protection and clothing,
and follow instructions carefully.
Reagent spills: If reagent spillage occurs, wipe up immediately
and rinse with plenty of water.
If reagent contacts skin, rinse the affected area thoroughly
with water. Avoid breathing released vapors.
Reagent vial disposal: Reagents contain different waste
pollutants. After use dispose of the reagent vials according to
the local regulations.
C 9800-01 Hanna Reactor (115 VAC)
C 9800-02 Hanna Reactor (230 VAC)
C 99 Hanna Photometer (for Laboratories)
C214 Hanna Photometer (for Wastewater
Treatment Application)
HI 740142 1 mL graduated syringe
HI 740143 1 mL graduated syringe (6 pcs)
HI 740216 Test tube cooling rack (25 holes)
HI 740217 Laboratory bench safety shield
Ι
SISTCODISO 12/03
www.hannainst.com
Range Reagent Sample
code q.ty
0-150 mg/L HI 93754F-25 2.0 mL
0-1000 mg/L HI 93754G-25 2.0 mL
HI 93754F-25 LR
HI 93754G-25 MR
COD
Chemical Oxygen Demand
ISO Reagents
Method
Instructions
General Description
Preliminary Examination
Health and Safety
Accessories
blank
sample
