![](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 7027-2:2019
Issue date: 2019 01 18
Water quality — Determination of turbidity — Part 2: Semi-quantitative methods for the assessment of transparency of waters
This document specifies the following semi-quantitative methods for the assessment of transparency of waters:
a) measurement of visual range using the transparency testing tube (applicable to transparent and slightly cloudy water), see Clause 4;
b) measurement of visual range in the upper water layers using the transparency testing disc (especially applicable to surface, bathing water, waste water and often used in marine monitoring), see 5.1;
c) measurement of visibility by divers in a destined depth, see 5.2.
NOTE The quantitative methods using optical turbidimeters or nephelometers are described in ISO 7027-1.