The LD-5R digital dust indicator is a relative concentration meter based on the light scattering method. It measures the dust level in less time than the filtrated collection method.
 
Due to its characteristics, the relative concentration may be converted into mass concentration with the use of the coefficient of conversion into mass concentration (K factor) calculated on the basis of the filtrated collection method.
 
The LD-5R PM2.5 digital dust indicator is a combination of the LD-5R with a PM2.5 cyclone particle size selector to perform the simplified measurement of PM2.5 concentrations