![](https://cdn.austrian-standards.at/thumbnail/shop/Product_Icons/118162/image-thumb__118162__as_book_product_detail_preview/Icon_ISO.png)
![](https://cdn.austrian-standards.at/thumbnail/shop/Product_Icons/118162/image-thumb__118162__as_organization_pdp_logo/Icon_ISO.png)
ISO 9964-3:1993
Issue date: 1993 04 28
Water quality — Determination of sodium and potassium — Part 3: Determination of sodium and potassium by flame emission spectrometry
The principle of the method specified is aspirating the sample into a gas flame of sufficient thermal energy to cause any sodium and potassium present to emit its characteristic radiation and measuring the intensity at a wavelength of 589,0 nm for sodium and 766,5 nm for potassium. Applies to water samples with a mass concentration of sodium and potassium of up to 10 mg/l. For higher concentrations, a smaller test portion is taken for analysis. The lower limits of determination are less than 0,1 mg/l for both sodium and potassium.