Original Articles
M. El Ouchy, K. El Ouedghiri M
Abstract
For the control and the monitoring of water quality, it is always necessary to use valid, reliable and reproducible methods. Measurements of the pH and electrical conductivity are among the obligatory analyzes of control for all types of water. These measurements are regulated and standardized, but they must be confirmed, thanks to experimental work, to validate the aptitude of use as well as the performances of these methods of analysis with an aim of using them in routine in a laboratory. This work presents the criteria of validation of the methods of control of the pH and electrical conductivity for the drinking water. Thus, we studied specificity, the calibration (linearity), the accuracy, fidelity (repeatability, intermediate fidelity, and reproducibility), the limit of quantification, the limit of detection and the uncertainty of measurement. These criteria were studied according to the requirements of the standards NM 03.7.001, NF T 90-2010, ISO 5725, ISO 17025 and the Rodier document. The validation of the methods of measurement of the pH and electrical conductivity was carried out within the unit of chemistry on the level of the Regional Diagnostic Laboratory Epidemiological and Environmental Health within of Regional Health Directorate of Fez city - Morocco. This laboratory have been adopted the standard ISO 17025, v 2005 in its services of analyzes since the year 2008.