Two types of high flow rate sampling heads and two versions of a low flow rate sampling head for collecting airborne dust on filter media are examined critically. The errors of the sampling train and sources of error in sample handling are described. The total precision for each of the four samplers is 5#x2013;6 r.s.d. as determined experimentally by gravimetrical and chemical analysis of the samples. Pairwise comparisons of different sampler types indicate an agreement within 10for one high flow rate sampler and both low flow rate samplers, provided a well homogenized aerosol is presented at moderate wind speeds.
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