What are my options for determining a change in my liquid particle counter’s operating characteristics?

Исследователь смотрит на пробирку с жидкостью
There are multiple ways to determine changes in liquid particle counter (LPC) operating characteristics. Using particle data from control samples collected over time combined with a statistical process control chart are useful resources for detecting a calibration change. Operators can also compare calibration curves over time to detect a change in calibration.

Changes can also be detected by analyzing a primary or secondary calibration suspension according to 6.2 and 6.3 and comparing the particle concentration data to the corresponding particle size distribution for the sample. If the results match within allowable limits, the instrument’s sizing and counting ability has not been significantly affected. If the results don’t align, a significant change has occurred.

An alternative method is to analyze a primary or secondary calibration suspension and resulting data as described above, followed by analyzing an ISO UFTD sample prepared in accordance with Annex A, and comparing the particle concentration data with the limits provided in Table A1. If the results match within allowable limits, the instrument’s sizing and counting ability has not been significantly affected. If the results don’t align, a significant change has occurred.

Finally, returning your liquid particle counter to the original manufacturer for evaluation and assessment of a calibration change is also an option.