What are the common methods and instruments used for water quality testing? What do I need to pay attention to?

What are the common methods and instruments used for water quality testing

The following are the common methods and instruments used for water quality testing:

Chemical analysis: This is the most traditional method of water quality testing, which mainly includes titration, spectrophotometry, colorimetry and so on. These methods are mainly through the reaction of chemical reagents and specific substances in the water to detect water quality parameters, such as total hardness, ammonia nitrogen, nitrate and so on.

Instrumental analysis: With the progress of science and technology, more and more instruments are used for water quality testing, such as spectrophotometer, spectrometer, chromatography and so on. These instruments can detect water quality parameters, such as total organic carbon (TOC), polycyclic aromatic hydrocarbons, etc. more quickly and accurately.

Biological detection method: certain microorganisms or biomarkers can also be used for water quality testing, such as algae, protozoa, bacteria and so on. These organisms can reflect the nutrient level of the water body, the degree of organic pollution and so on.

Online monitoring systems: These systems usually include sensors and data collectors, which can monitor various parameters of water quality in real time, such as temperature, pH, dissolved oxygen, etc.. Online monitoring systems generally require regular calibration and maintenance.

When conducting water quality testing, the following matters need to be noted:

Sampling point selection: the choice of sampling points should be representative, able to reflect the water quality of the entire water body. At the same time, the sampling point should be far away from the source of pollution to ensure that the collected water samples are not affected.

Calibration and maintenance of instruments: All testing instruments need to be calibrated and maintained regularly to ensure their accuracy and stability. In addition, the expiration dates of reagents should be checked regularly and expired reagents should be replaced in a timely manner.

Laboratory safety: When conducting water quality testing, you need to pay attention to laboratory safety, such as wearing protective clothing, avoid direct contact with toxic and hazardous substances.

Data processing and analysis: test data need to be processed and analyzed in a timely manner to draw accurate conclusions. Data should be analyzed using appropriate statistical methods to avoid the impact of data fluctuations on the results.

Reporting of results: Test results need to be reported to relevant organizations or the public in a timely manner. The report should be clear and concise, including the location of sampling points, testing items, testing methods, and testing results.

Quality control: In order to ensure the accuracy and reliability of water quality testing, strict quality control is required. This includes quality control within the laboratory and external quality supervision. Internal laboratory quality control can be carried out through repeated testing, spiking recovery, etc.; external quality supervision can be carried out through participation in laboratory comparison, proficiency testing, etc..

Records and archives management: water quality testing records and files is an important part of the water quality testing work. These records and files should include sampling records, testing records, instrument use records, reagent use records. Records and files should be properly preserved for future reference and analysis.

Personnel training and management: personnel engaged in water quality testing need to be professionally trained, with the appropriate skills and knowledge. At the same time, personnel management should establish a sound system and process, including personnel recruitment, training, assessment, promotion and so on.

Emergency plan: for possible emergencies, such as instrument failure, data anomalies, etc., emergency plans should be developed. The emergency plan should include the emergency response process, spare parts reserve, personnel deployment and so on.

Compliance and certification: water quality testing should be in accordance with relevant laws, regulations and standards. For the need to issue a statutory report of the testing program, should obtain the appropriate qualification and metrological certification. In addition, in order to improve the quality and credibility of water quality testing work, can participate in international or regional quality certification system certification.

Water quality meter