1 Scope
This International Standard specifies the application of dynamic light scattering
(DLS) to the measurement of average hydrodynamic particle size and the measurement of the size distribution of mainly submicrometre-sized particles, emulsions or fine bubbles dispersed in liquids. DLS is also referred to as quasi-elastic
light scattering (QELS) and photon correlation spectroscopy (PCS), although it actually
is one of the measurement techniques.
This International Standard is applicable to the measurement of a broad range of dilute
and concentrated suspensions. The principle of dynamic light scattering for a concentrated
suspension is the same as for a dilute suspension. However, specific requirements
for the instrument set-up and specification of test sample preparation are required
for concentrated suspensions. At high concentrations, particle-particle interactions and multiple light scattering can become dominant and may result in
apparent particle sizes that differ between concentrated and dilute suspensions.