RO
SR EN ISO 7393-2:2018
Water quality - Determination of free chlorine and total chlorine - Part 2: Colorimetric method using N,N-dialkyl-1,4-phenylenediamine, for routine control purposes (ISO 7393-2:2017)
ISO 7393-2:2017 specifies a method for the determination of free chlorine and total chlorine in water, readily applicable to lab- and field-testing. It is based on measurement of the absorption, the red DPD colour complex in a photometer or the colour intensity by visual comparison of the colour with a scale of standards that is regularly calibrated. This method is appropriate for drinking water and other waters, where additional halogens like bromine, iodine and other oxidizing agents are present in almost negligible amounts. Seawater and waters containing bromides and iodides comprise a group for which special procedures are to be carried out. This method is in practice applicable to concentrations, in terms of chlorine (Cl2), from, for example, 0,000 4 mmol/l to 0,07 mmol/l (e.g. 0,03 mg/l to 5 mg/l) total chlorine. For higher concentrations, the test portion is diluted. Commonly, the method is applied as a field method with mobile photometers and commercially available ready-for-use reagents (liquid reagents, powders and tablets). It is essential that those reagents comply
Status :
Valid
Approval date : 6/29/2018
Number of pages : 24
ICS : 13.060.50 Examination of water for chimical substances
Technical Committee : 52 - Water quality
- Replaces SR EN ISO 7393-2:2002
- Normative reference SR EN ISO 3696:2002
- Normative reference SR EN ISO 5667-3:2018
- Normative reference SR ISO 8466-1:1999