Are the COD2 reagent vials are a good alternative to the regular COD reagent?

Document ID

Document ID TE253

Version

Version 4.0

Status

Status Published

Published Date

Published Date 25/01/2018
Question
Are the COD2 reagent vials are a good alternative to the regular COD reagent?
Summary
COD vs COD2
Answer
Before switching to COD2 reagents, consider the following:

-COD2 vials are not EPA approved and are only acceptable for non-reporting purposes.
-Chloride and ammonia are interferences for the COD2 vials. If the concentration of these compounds exceed 200 mg/L chloride and 50 mg/L ammonia then regular COD vials are recommended.
-Chloride must be present in the sample in order for ammonia to interfere significantly. If chloride is not present in your sample, ammonia levels can exceed 50 mg/L without causing interference.

You should check with your regulator if you will be reporting these results before switching.

For more information on COD and COD2 please see the article titled, Does Hach have any literature on Chemical Oxygen Demand (COD) testing?