Leo Harper
Particle diameter and particle-number concentration answer different questions, so choose a counter standard by evaluating both. Diameter identifies the size reference your documented method requires. Concentration tells you how many
“NIST-traceable” does not mean a particle standard has approval from the National Institute of Standards and Technology (NIST). Traceability applies to a specified measurement result—such as a particle diameter assigned
Here’s how to choose particle counter calibration standards: start with the instrument’s documented procedure, then match diameter, material, format, measurement medium, concentration, documentation, and handling requirements. A cleanroom class or
Performing calibration and verification in accordance with ISO 21501-4 helps ensure that light-scattering airborne particle counters (LSAPCs) produce reliable particle sizing and concentration measurements. Instruments conforming to this document are
Your SSIS tool calibration is only as valid as the PSL size you select. Order the wrong size from a 18-option catalog and your scanner will produce size response data
Calibration wafer standards for thin film measurement can be purchased from specialized semiconductor metrology suppliers that support thickness measurement, surface characterization, and process control applications. These suppliers provide calibration wafers
Choosing the right dry silica microsphere size depends primarily on your instrument’s detection range, the specific application (such as aerosol testing or semiconductor validation), and the accuracy requirements dictated by
Dry silica microspheres are solid, non-porous particles composed of silicon dioxide (SiO₂), manufactured to precise spherical geometries and tight size distributions. Dry silica microspheres are used as particle size standards
Dry silica microspheres are solid SiO₂ particles supplied as a dry powder, while Polystyrene spheres are polymer microspheres, typically dispersed in a de-ionized water suspension. The original term for polystyrene
Neutral buoyancy of a cleanroom fog, in the context of airflow visualization, describes the condition where aerosol fog droplets remain suspended in the air column long enough to faithfully trace the movement of