H2O Lab-News

How will the REACH regulation on Chromium VI affect your COD analysis?

Chromium VI (Cr VI), one of the essential reagents in COD analysis, is listed as a "Substance of Very High Concern" on the Annex XIV list of the European Union's REACH regulation.
This does not mean that Chromium VI COD will be banned completely.

For you as a user there will be no change. The usage of Chromium VI will still be allowed for "scientific research & development". According to the European Chemical Agency (ECHA) this includes water monitoring via cuvette tests.
However, from September 2017 producers of COD tests need to have EU authorisation to sell these tests.

HACH LANGE has already started the lenghty application process for authorisation.  This work is likely to continue through 2015 but is planned to complete well before September 2017.  Our intention is to ensure continuity of supply and peace of mind for customers using this critical control parameter. We will continue to keep you up to date on this subject as we move closer to REACH deadlines.

Read on to learn more about this important sum parameter!

TOC - An alternative to COD?

At HACH LANGE we place very high regard on our environmental responsibility. In comparison to traditional standard analysis the COD cuvette test uses small amounts of reagents. Users are protected from direct contact with reagents by the design of the cuvette and its use as a digestion and evaluation vessel without any decanting etc. Used COD reagents are treated at our own state of the art Environmental Centre with a recycling rate of more than 80%.
Concern for user safety is built-in to our tests but COD analysis in general has been scrutinised for more than 25 years because of hazardous ingredients, with some countries introducing TOC as an alternative sum parameter.

What do you need to know about COD/TOC correlation?
COD is an important monitoring parameter for the efficiency of municipal and industrial wastewater treatment plants. Whist there is a rule of thumb of TOC × 4=COD, in many cases it is not possible to use a fixed correlation factor when switching to TOC. TOC measures the total organic carbon, while COD measures oxygen demand. COD is thus more closely related to the cleaning process of the plant. Any measure that does not correctly correlate could lead to plant performance issues.  

It is recommended to monitor influent and effluent for a longer period of time with COD and TOC in parallel, in order to be able to recognise anomalies when they occur. This is especially true for WWTPs with varying industrial discharges. Nearly 20 years ago HACH LANGE was the first to introduce TOC cuvette tests. Benefit from our experience now!

Please contact us if you want support in setting up a monitoring strategy. A switch to TOC is practical for certain plants but this must be carefully prepared and implemented.

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Literature to support you in your daily work.

Independent tests showed that there is no risk to your health while working with HACH LANGE COD cuvette tests in accordance with the operating instructions.
Click here to download the PDF file

COD is still one of the most important parameters in wastewater analysis: For assessing wastewater and water, and the control of wastewater treatment plants. The determination of COD with the cuvette test system offers numerous advantages.
Click here to download the PDF file

In recent years, TOC has steadily gained in importance in wastewater analysis. In relationship to COD in particular, it provides specific information about the type and origin of organic loads in wastewater. Advances have also been made in TOC analysis – no longer is major investment required, either financially or in terms of equipment.
Click here to download the PDF file

The TOC cuvette tests from HACH LANGE are unique in their use of an automated shaker to purge TIC: Saving time, eliminate the risk of human error and contamination!
Click here to download the PDF file

Additional information from local ECHA helpdesks

Exemption for the use of Annex XIV substances in analytical activities

HACH LANGE solutions deliver to you a perfectly coordinated system for lab and process analysis.

Cuvette tests for COD: minimum amounts of reagents, maximum safety
Pre-dosed reagents for maximum safety. Easy to use and photometric evaluation, packaged in a fully equipped box. Officially approved for consent limits. Environmentally friendly due to less chemicals.

  • 10 different standard measuring ranges to meet any need
  • Special measuring range for samples with high Chloride loads
  • Two measuring ranges according to ISO 15705 requirements

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 Cuvette tests for TOC: unique timesaving system

  • Convenient choice of three measuring ranges
  • All reagents are present in the cuvette in the right amounts
  • TOC-X5 shaker prepares up to eight samples simultaneously
  • Benefit from almost 20 years of experience in TOC cuvette tests

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AP 3900: Fully automated wastewater analysis

The AP 3900 is a robot that not only measures one cuvette test after another, but also processes up to ten samples in parallel, with six different parameters at the same time. Even if you have to measure another cuvette test at short notice during the analysis!

  • Increases productivity and flexibility
  • Saves time and costs
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 BIOTECTOR B7000 online TOC analyser

Complete TOC/TN measuring solution, from sample preparation to outlet. The system is available with a wide range of options.
  • Outstanding durability
  • Flexible field of application
  • High measurement accuracy
  • Extended up-time via various service options

Request more information now!
TOC Starter Kit
Do you want to know your TOC/COD correlation? Get started now!

Choose from these measuring ranges:
  • LCK385: 3-30 mg/L C
  • LCK386: 30-300 mg/L C
  • LCK387: 300-3000 mg/L C

The TOC-X5 shaker prepares up to 8 samples in just 5 minutes; reliable results without cross-contamination.

Get your starter kit now for just £460.

Request a quote now!
Orders must be placed by May 31st 2014. Offer Code H1415L must be mentioned at time of purchase. Not to be combined with any other offers or discounts.