Chemical Oxygen Demand
(COD)
www.chemetrics.com | 1.800.356.3072
The CHEMetrics COD System
All Materials for COD Lab Setup are available
from CHEMetrics
4 COD Reagent Vials Kit (USEPA-accepted and Mercury-free)
4 D
igestor Block (holds 12 vials)
4 P
hotometer (single or multi-analyte)
4 C
alibration Standards (1000 and 10,000 ppm)
4 C
OD Vial Rack (holds 40 vials)
Methods The Dichromate Reactor Digestion Method
USEPA-accepted CHEMetrics offers two methods *(USEPA-accepted
USEPA-accepted
The determination of
and Mercury-free) for the determination of low-,
Chemical Oxygen Demand
mid-, and high-range COD levels in wastewater.
(COD) is widely used in
The products using the USEPA-accepted method
municipal and industrial laboratories to measure the
contain mercuric sulfate in the reagent to eliminate
overall level of organic contamination in wastewater.
chloride interferences. The Mercury-free product line
The contamination level is determined by measuring
is applicable when chloride interference is not a
the equivalent amount of oxygen required to oxidize
concern and USEPA reporting is not required.
organic matter in the sample.
CHEMetrics’ leakproof reagent vials contain pre-
References: USEPA Methods of Analysis of Water
measured solutions of sulfuric acid and potassium
and Wastes, Method 410.4 (1983). APHA Standard
dichromate. To perform the COD determination, the
Methods, 22nd ed., Method 5220 D - 1997. A.M. Jirka
analyst simply removes the Teflon-lined screw cap from
and M. J. Carter, “Micro Semi-Automated Analysis
the vial, adds sample to the vial, and replaces the cap.
of Surface and Wastewaters for Chemical Oxygen
The vial is then heated for two hours at 150°C in a
Demand,” Analytical Chemistry, Vol. 47, p. 1397 (1975).
standard digestor block.
J. A. Winter, “Method Research Study 3, Demand
Analysis, An Evaluation of Analytical Methods for Results are obtained using any photometer or
Water and Wastewater,” USEPA, 1971. ASTM D 1252- spectrophotometer that accepts a 16 mm cell including
00, Chemical Oxygen Demand (Dichromate Oxygen Hach instruments with factory-programmed calibra-
Demand) of Water, Test Method B. tions1. A generic calibration equation is included for
use with other spectrophotometers.
NOTE: No endorsement by Hach Company is implied or intended.
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www.chemetrics.com | 1.800.356.3072
Instrumental Kits
Range: 0-1500 ppm (HR)
Multi-Analyte Photometer Method: Dichromate Reactor Digestion
V-2000
(See page 14 for instrumental features) Cat#
COD (Mercury-free) Vials Kit K-7361S
Range: 0-150 ppm (LR) Kit comes in a cardboard box and contains everything needed to perform up
Method: Dichromate Reactor Digestion to 24 tests (except distilled water): 25 vials and instruction book.
Cat#
COD (Mercury-free) Vials Kit K-7366
COD (USEPA-accepted) Vials Kit *K-7350S
Kit comes in a cardboard box and contains everything needed to perform up
Kit comes in a cardboard box and contains everything needed to perform up to 149 tests (except distilled water): 150 vials and instruction book.
to 24 tests (except distilled water): 25 vials and instruction book.
COD (USEPA-accepted) Vials Kit *K-7355 Range: 0-15,000 ppm (HR+)
Kit comes in a cardboard box and contains everything needed to perform up Method: Dichromate Reactor Digestion
to 149 tests (except distilled water): 150 vials and instruction book.
Cat#
COD (Not USEPA-accepted) Vials Kit *K-7370S
Range: 0-150 ppm (LR) Kit comes in a cardboard box and contains everything needed to perform up
Method: Dichromate Reactor Digestion to 24 tests (except distilled water): 25 vials and instruction book.
Cat#
COD (Not USEPA-accepted) Vials Kit *K-7375
COD (Mercury-free) Vials Kit K-7351S
Kit comes in a cardboard box and contains everything needed to perform up
Kit comes in a cardboard box and contains everything needed to perform up to 97 tests (except distilled water): 98 vials and instruction book.
to 24 tests (except distilled water): 25 vials and instruction book.
COD (Mercury-free) Vials Kit K-7356
Range: 0-15,000 ppm (HR+)
Kit comes in a cardboard box and contains everything needed to perform up Method: Dichromate Reactor Digestion
to 149 tests (except distilled water): 150 vials and instruction book.
Cat#
COD (Mercury-free) Vials Kit K-7371S
Range: 0-1500 ppm (HR) Kit comes in a cardboard box and contains everything needed to perform up
Method: Dichromate Reactor Digestion to 24 tests (except distilled water): 25 vials and instruction book.
Cat#
COD (Mercury-free) Vials Kit K-7376
COD (USEPA-accepted) Vials Kit *K-7360S
Kit comes in a cardboard box and contains everything needed to perform up
Kit comes in a cardboard box and contains everything needed to perform up to 97 tests (except distilled water): 98 vials and instruction book.
to 24 tests (except distilled water): 25 vials and instruction book.
COD (USEPA-accepted) Vials Kit *K-7365 All COD Kits require the use of a Digestor Block along with a
CHEMetrics Photometer, a COD Photometer, or a spectrophotometer
Kit comes in a cardboard box and contains everything needed to perform up capable of accepting a 16 mm round cell. Instruments sold separately.
to 149 tests (except distilled water): 150 vials and instruction book.
A fresh reagent ampoule blank must be prepared for each series of
tests; therefore the number of samples that can be tested with each
See Product Price List for COD Quantity Discount Schedule. kit will vary.
Instructions and SDSs are posted on website.
If no shelf-life is listed for a product, then the shelf-life is at least 2 years. Accessories
Description Cat#
Vial Rack (holds 40 vials) A-0107
COD Zeroing Vial A-0183
Digestor Block US (115 Volt, 12 cells), Warranty 1 year A-0201
Calibration Standard, 1000 ppm (200 mL), Shelf-life 8 months A-73011
Calibration Standard, 10,000 ppm (200 mL), Shelf-life 8 months A-73101
Low Range COD Photometer (0-150 ppm) A-7320
High Range COD Photometer (0-1500 & 0-15,000 ppm) A-7325
This product must be refrigerated.
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*Contains mercury. Dispose according to local, state or federal laws.
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