What is ISO/TR 17534-4 about?
ISO/TR 22814 provides practical guidance for performing and interpreting measurements using dynamic light scattering (DLS) that goes beyond the treatment of measurement artifacts. ISO/TR 22814 is intended to help users with experiments planning, in particular with respect to obtaining the necessary information on the sample and deciding whether DLS is the most appropriate method.
ISO/TR 22814 provides information on how to prepare samples in an appropriate way, verify the proper functioning of the instrument, and interpret the data correctly, including ways to assess data quality. ISO/TR 22814 focuses on the practical steps required to obtain DLS results of excellent quality, rather than on theoretical considerations, and covers not only the measurement of solid particles but also emulsions and bubbles.
Who is ISO/TR 22814 for?
ISO/TR 22814 on good practice for dynamic light scattering (DLS) measurements is relevant to:
- Testing authorities
- Spectroscopists
- Metrologists
- Physiochemical engineers
Why should you use ISO/TR 22814?
DLS measures the hydrodynamic particle size, which includes the electrical double layer surrounding the particle. Other measurement techniques, for example, laser diffraction, measure the volume equivalent particle size based on the physical dimensions of the particle itself.
ISO/TR 22814 is about Dynamic light scattering (DLS), which is a widely used technique for the characterization of particles with equivalent hydrodynamic diameters below a few micro meters. DLS is a method based on first principles and does not require calibration by the user with a particle size reference material. However, the metrological traceability of the DLS results depends on the accuracy of several input factors that are verified at regular intervals. In addition, the method performance is checked at regular intervals to ensure reliability.
ISO/TR 22814 provides modern instruments that allow users with minimal training or background to use this technique. ISO/TR 22814 has been developed as guidance for good practice in DLS and complements. Good practice, as it relates to instrument type, depends on the scattering angle used for the measurement.
Overall, ISO/TR 22814 is helpful as it provides the analyst with basic information about the sample, it is equally important for the customer or submitter to stipulate the purpose and desired outcome of the analysis. ISO/TR 22814 determines the level of effort expended and aids the analyst in the experimental design.
