The effect of size-selective samplers (cyclones) on XRD response

The study evaluated five size-selective samplers used in the South African mining industry to determine how their performance affects the X-ray powder diffraction (XRD) response when respirable dust samples are analysed for quartz using direct-on-filter XRD. The samplers' performance was analysed with three test dusts in an aerosol dust chamber as described in MDHS 101. The performance of size-selective samplers was found to affect the XRD response during quartz analysis and the quartz concentration measured. The performance of each sampler also changed when a different type of dust was used. Factors contributing to the XRD response were the distribution of dust on the filter, the particle size distribution of the dust sampled and the performance of the sampler. Recommendations are that a national sampler be used during the sam- pling of airborne dust at mines and at laboratories and that a national quality assurance protocol be developed to evaluate the sampler.