To check the uniformity of particle suspension, it is recommended to perform three equal volume particle counts on the liquid sample, and the repeatability must meet certain requirements before taking the average as the final test result (the deviation between the three counts of the smallest particle size detected must be within 10%); Otherwise, the test results cannot be averaged and must be retested.

When using a liquid particle counter to detect liquid samples, extra caution must be taken if the measured liquid sample is incompatible with the previous one. There may be liquid film or droplets from the last detected liquid sample on the sensor window, which can cause incorrect particle counting. Therefore, when replacing the liquid sample, a series of solvents should be used to clean the channel of the sensor. When using a liquid particle counter to detect liquid samples, extra caution must be taken if the measured liquid sample is incompatible with the previous one. There may be liquid film or droplets from the last detected liquid sample on the sensor window, which can cause incorrect particle counting. Therefore, when replacing the liquid sample, a series of solvents should be used to clean the channel of the sensor.

When detecting liquid samples such as petroleum ether and gasoline, due to their low viscosity and high volatility, if a higher working flow rate is used for testing, the liquid sample will easily vaporize and form bubbles when passing through the sensor window at high speed, causing counting errors. Therefore, the sampling flow rate for detection should be reduced to at least 30ml/min.

To ensure uniform particle suspension and improve the repeatability of detection results, a desktop liquid particle counter is generally equipped with a magnetic stirrer inside. If the detected liquid sample contains ferromagnetic particles, the ferromagnetic particles will quickly settle under the magnetic field of the magnetic stirrer, thereby affecting the detection results. Therefore, if it is suspected that the detected liquid sample contains ferromagnetic particles, the magnetic stirrer should be turned off first before using a liquid particle counter for detection.

When using a liquid particle counter to detect oil-based liquid samples, the instrument counts free water in the oil sample as particles, causing counting errors. A normal oil sample should be clear and transparent. When the oil sample contains free water, it will appear cloudy and opaque from the appearance. When using a liquid particle counter for detection, the number of particles between 15-25 μ m will significantly increase, resulting in abnormal particle size distribution.

When there is suspicion of water content in the oil sample, heating treatment can be carried out to allow the water to evaporate before testing.

When using a liquid particle counter to detect oil-based liquid samples, the instrument will also count the bubbles in the liquid sample as particles, causing counting errors. When there are bubbles in the liquid sample, if a liquid particle counter is used for analysis, the number of particles above 100 μ m will significantly increase, and the particle size distribution will appear abnormal. In this case, ultrasonic or vacuum methods are used to remove gas from the liquid sample.