Sizing Accuracy of a LiQuilaz-S Particle Counter

The need to verify the performance of a volumetric Optical Particle Counter (OPC) is necessary in many applications. This paper describes the correct method to verify the performance of a LiQuilaz-S series optical particle counter by calculating the sizing accuracy. In order to calculate the sizing accuracy, you must precisely collect particle count data and know the instrument’s resolution. These instructions apply to collecting data in Facility Net software using LiQuilaz-S series volumetric spectrometers.

Accurate sizing and counting have implications in qualifying chemical delivery systems, accepting incoming chemicals, or qualifying incoming parts. Therefore, the need for optical particle counters to match and a way to qualify their performance is thus very important to many users. To verify an OPC, one must use appropriate methods to ensure time and or money is not wasted. These methods include good laboratory technique, proper equipment set up, data collection, and using the sizing calculator, as described in this paper. Particle Measuring Systems (PMS) uses sizing accuracy to verify the performance of our LiQuilaz-S OPCs.

The LiQuilaz is a volumetric instrument that counts 100% of the particles passing through the sensor. 100% of the fluid passing through the capillary is analyzed because the capillary is fully illuminated by the laser beam, as shown in the image here. Therefore, the LiQuilaz will always count 100% of the particles eliminating the need to perform count standard tests. Counting Accuracy refers to the instruments ability to count the correct concentration of particles in a solution. Sizing Accuracy refers to the instruments ability to correctly determine the size of a Polystyrene Latex Sphere (PSL).

Interested in learning more?  This paper details how to conduct the test and understand the results.