Key Points for Regular Calibration and Maintenance of COD Analyzers

COD analyzers are widely used and crucial instruments in water quality testing, playing a key role in monitoring chemical oxygen demand (COD). To ensure the accuracy and long-term stability of test results, regular calibration and scientific maintenance are essential. Proper calibration and maintenance not only extend the lifespan of the equipment but also effectively avoid detection errors and ensure the reliability of monitoring data.

Regular calibration is the core element in maintaining the accuracy of COD analyzers. Because analyzers are affected by various factors such as temperature, humidity, light source aging, and reagent concentration changes during long-term use, it is recommended that users perform calibration according to the manufacturer's requirements or laboratory standard cycles. Generally, instruments with frequent daily testing should be calibrated with standard samples weekly or monthly to ensure that the comparison error between the measurement results and the standard solution remains within a reasonable range. Freshly prepared standard solutions should be used during calibration, and comparison and correction should be strictly performed according to the operating procedures.

Maintenance is an important measure to ensure the stable operation of the instrument. COD analyzers are susceptible to the effects of reagent residue, reaction tube fouling, and optical component contamination during long-term operation. Therefore, reaction flasks, colorimetric tubes, and optical detection windows should be cleaned regularly to prevent the accumulation of organic matter that could cause measurement errors. For automated COD analyzers, reagent delivery lines should also be checked regularly for blockages or leaks, and aging components should be replaced promptly to prevent impact on detection efficiency.

Environmental management is also an essential aspect of maintenance. COD analyzers should be placed in a dry, well-ventilated experimental environment free from strong magnetic interference, avoiding direct sunlight and high temperature and humidity conditions that could damage the optical system. If the equipment is not used for an extended period, reagents should be emptied and the equipment kept clean to prevent residual liquid from crystallizing and clogging the lines.

Regular calibration and maintenance of COD analyzers are crucial for ensuring accurate test results and stable equipment operation. Scientific management and standardized operation not only improve work efficiency but also provide more reliable data support for water quality monitoring and environmental management.