THE PURPOSE AND APPLICATION OF ISO 21501 （的目的和应用ISO 21501）.pdf

THE PURPOSE AND APPLICATION OF ISO 21501-4 APPLICATION NOTE CC-117 (US) Introduction ISO 21501 is titled “Determination of particle size distribution – Single particle light interaction methods” and consists of 4 parts. Part 4: Light scattering airborne particle counter for clean spaces applies to handheld, portable and remote airborne particle counters used in cleanrooms. This standard was released in 2007, and, together with ISO 21501-2 and 21501-3, replaces ISO 13323- 1:2000. The purpose of ISO 21501-4 is “to provide a calibration procedure and verification method for particle counters, so as to minimize the inaccuracy in the measurement result by a counter, as well as the differences in the results measured by different instruments.” ISO 21501-4 sets minimum performance standards for airborne particle counters and defined methods for calibration and verification of performance. While standards existed previously that covered these topics, none were as comprehensive as ISO 21501-4. Scope of ISO 21501-4 Table 1 shows the parameters that are listed within ISO 21501-4 and the accompanying requirements. In addition, ISO 21501-4 requires that the calibration particles have a standard uncertainty of the mean particle size ≤ ±2.5%, defines the minimu