The document specifies a method to check one of the cleaniness aspects of feather and down ready to be used throught the determination of the amount of undissolved and solved matter present in the aqueous extract.
DIN EN 1164:1998 history
1998DIN EN 1164:1998-10 Feather and down - Test methods - Determination of the turbidity of an aqueous extract; German version EN 1164:1998
1998DIN EN 1164:1998 Feather and down - Test methods - Determination of the turbidity of an aqueous extract; German version EN 1164:1998