Water quality monitoring is a prerequisite to ensure safe water, and the quality of drinking water is directly related to people's health. In order to protect the water environment, it is necessary to strengthen the monitoring of sewage discharge. The quality of drinking water has declined, which is extremely harmful to human health. Only by strictly testing drinking water can the safety of drinking water be guaranteed.
Water quality detector, a professional instrument used to analyze the content of water quality components, plays an important role in environmental protection, water quality testing and water resources protection. So, how should we choose a water quality detector?
I. Identify what indicators need to be tested for the tested water sample
1. Main indicators: COD, ammonia nitrogen, total phosphorus, total nitrogen;
2. Special indicators: heavy metals (copper, iron, nickel, lead, zinc, chromium, etc.), oil content, BOD, etc.;
3. Conventional indicators: turbidity, chroma, PH, dissolved oxygen, etc.
II. Determine what testing standard is used for the inspected object
Standards usually used include China's current testing standards (National Standard GB, Ministry Standard JB, Industrial Standard HB), and international standards ISO or American Standard ASMI, etc.
III. Determine what method to use
1. Destructive (a detection method of taking part of the inspected article or deforming it, the detection accuracy is high but the detection speed is slow): chemical analysis, physical test.
2. Non-destructive (a detection method that does not damage the inspected items, the detection accuracy is relatively low but the detection speed is fast): radiation, sound wave, electromagnetic, penetration, mirror phase.
IV. Detection accuracy and scope of application
According to the maximum and minimum detection quantities of the inspected items, combined with the three aspects 1, 2, and 3 mentioned above, select the closest accuracy and range value.
V. Materials and internal structure
The use of the instrument should be reliable. Most of the testing instruments belong to the fatigue test motion mechanism. The stability of the material and internal structure determines the service life of the instrument. If the quality of the instrument is not ideal, it will seriously affect the accuracy of the instrument's measurement after long-term use, and even the measurement cannot be continued. So remind the majority of users to have a preliminary understanding of this before buying, to avoid such things from happening.
