DIN 38405-13:1981-02

1 General information and concepts
2 Quantitative determination
      2.1 Determination of total cyanide
             2.1.1 Decomposition of the cyanides and
                      separation of the cyanide of hydrogen
             2.1.2 Titrimetric determination by means of
                      silver nitrate
                      2.1.2.1 End-point determination by
                                 observation of the Tyndall
                                 effect
                      2.1.2.2 End-point determination by
                                 use of the indicator
                                 o-dimethylaminobenzylidene-
                                 rhodanine
             2.1.3 Photometric determinations by means of
                      barbituric acid-pyridine
      2.2 Determination of the readily liberatable cyanide
             2.2.1 Liberation and separation of the cyanide
                      of hydrogen
             2.2.2 Titrimetric determination by means of
                      silver nitrate
                      2.2.2.1 End-point determination by
                                 observation of the Tyndall
                                 effect
                      2.2.2.2 End-point determination by
                                 use of the indicator
                                 p-dimethylaminobenzylidene-
                                 rhodanine
             2.2.3 Photometric determinations by means of
                      barbituric acid-pyridine
      2.3 Determination of the cyanogen chloride

Specifies cyanides that may be present in the water by virtue of the introduction of trade wastes in dissolved and/or undissolved form. They may be present in the form of cyanide of hydrogen, of cyanide ions, of complex-bonded cyanides, of organic compounds containing cyanogen groups, and in the form of cyanogen chloride.