ISO 7766:2003 写真廃棄物の処理—シアン化物の分析—分光分析によるヘキサシアノ鉄酸塩（II）およびヘキサシアノ鉄酸塩（III）の測定 | ページ 2

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 7766 was prepared by Technical Committee ISO/TC 42, Photography.

Introduction

This International Standard is devoted to the analysis of photographic wastes; it encompasses the analysis of complexed iron cyanides (hexacyanoferrates) in photographic effluents.

Some of the chemicals specified in the test procedures are caustic, toxic, or otherwise hazardous. Specific warning, caution and danger notices are noted but, in addition, the normal precautions required during the performance of any chemical procedure should be exercised at all times.

In the case of effluents, the photographic laboratory can best establish conformity to regulations by appropriate chemical analysis. In some cases, in-house analyses will be possible; but the use of an outside laboratory will often be required.

Complexed cyanides are used in the bleaching stage of colour photographic processing and it is, therefore, possible for the cyanide portion of the resulting photographic effluent to reach a reportable level. Complexed cyanides contribute to the total cyanides in those tests in which the sample preparation breaks down the complexed cyanides. It is the purpose of this International Standard to provide a method giving an independent determination of the cyanide present as hexacyanoferrate complexes. Due to the chemical behaviour of cyanide complexes, it is not possible to specify a single method for the quantitative determination of complexed cyanides in these effluents.

The analysis of cyanide is covered in various aspects in the following International Standards:

• ISO 6703-1:1984, Water quality — Determination of cyanide — Part 1: Determination of total cyanide;
• ISO 6703-2:1984, Water quality — Determination of cyanide — Part 2: Determination of easily liberatable cyanide.

1 Scope

This International Standard establishes a test method for the determination of hexacyanoferrate(II) (ferrocyanide) and hexacyanoferrate(III) (ferricyanide), referred to hereafter as Fe(CN)₆, in photographic processing effluents ¹⁾ . Results are reported as hexacyanoferrate, Fe(CN)₆.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

Bibliography