EN ISO 7393-1 : 2000

National foreword
0 Introduction
1 Scope and field of application
2 Definitions
3 Principle
4 Reagents
5 Apparatus
6 Procedure
7 Correction of interference due to the presence of
      oxidized manganese
8 Expression of results
9 Interferences
10 Test report
Annex A - Separate determinations of combined chlorine of
          the monochloramine type, combined chlorine of
          the dichloramine type and of combined chlorine
          in the form of nitrogen trichloride
Annex B - Preparation of water free from oxidizing and
          reducing substances
Bibliography
Table 1 - Terms and synonyms in relation to actual compounds
          in the solution
Table 2 - Analytical parameters from interlaboratory analysis
          for free residual chlorine

Defines a titrimetric procedure to determine free chlorine and total chlorine in water. This method applies to concentrations, in terms of chlorine, (Cl2), from 0,0004 to 0,07 mmol/l (0,03 to 5 mg/l) total chlorine and at higher concentrations by dilution of samples. For concentrations above 0,07 mmol/l, ISO 7393-3 also applies. Sea water and waters containing iodides and bromides require special procedures.