ISO 5667-14-2014 pdf free download

ISO 5667-14-2014 pdf free download.Water quality — Sampling — Part 14:Guidance on quality assurance and quality control of environmental water sampling and handling
Qualité de I’eau — Echantillonnage — Partie 14: Lignes directrices pour le contrôle de Ia qualité dans I’échantillonnage et la man utention des eaux environneinentales.
7.3 Field measurements
The on-site measurements should be performed before the actual sampling, since they might still be able to give instructions that should be followed for sampling. The measurements can either be performed directly in the medium to be sampled, or in a spot sample to be discarded after the measurement. In scoop or sample collection containers, sensors or electrodes should not be used in combination because the use of various sensors could contribute to the contamination of the sample.Wl
It is important to ensure that on-site instruments are regularly calibrated. Functional tests and calibrations as well as the type of documentation are set for each parameter in the operation instruction. On-site verification of equipment in situ before and after series of measurement should be performed.
Measure and record the temperature of the sample on the site. Physical parameters (for example pH, dissolved gases, suspended solids) should be determined on-site, or as soon as possible afterwards. The p1-f-measurement in ion-poor waters with low buffering capacity or in saline waters requires special measuring conditions. For certain oxygen sensors, a minimum flow or agitation should be guaranteed. Provide alternative sensors in case of breakage.
The results of these operations (metrological control of field devices, management of calibration solutions) should be recorded and stored.
7.4 Taking the samples
7.4.1 Spot samples
Spot samples are needed to capture the current state with regard to time and/or location from a body of water. They should be taken in particular when a short-term change in the concentration of the analytes to be determined is to be expected in the sample. The reasons for this can be strong outgassing, faster degradation, adsorption or contamination. When scooping the sample by means of suitable devices, these effects are reduced.
The direct filling of the spot sample into the sample container should be favoured. The material of the vessel used should be selected according to the study parameters. Contamination ofthe sample by liquid or solid deposits to the sampling equipment should be excluded.
For further information, see ISO 5667-1 and the specific standards appropriate to the type of water under study in the ISO 5667-series.
In some cases, the sample container should be closed airtight and with no gas space above the liquid after filling.ISO 5667-14-2014 pdf free download.