This International Standard gives methods for deter-mining the silver content in photographic effluents from photographic processing wastes. Sampling, sample preservation and analytical methodology are included.
Three analytical procedures are given with two sup-porting sample treatment methodologies:
a) a flame atomic absorption spectroscopy (AAS) method;
b) two potentiometric iodide titration (PT) methods.
The choice of treatment is dependent on the analysis method and form of sample. Where AAS is the cho-sen method for analysis, cyanogen iodide-treated or preserved samples may be analysed directly. For the PT method, two digestion procedures are given: Di-gestion A for effluents with low salt content, and Di-gestion B for samples with high solids content.