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Since the early seventies, the High Volume Sampler was the most
common and widely used dust sampler for ambient air. Dust is sampled
on a filter with a sampling rate of 100 m³/hr. Usually, filters
are changed every 24 hours. The sampled dust is called Total Suspended
Matter (TSP). However, in several studies since 1977 it was shown
that sampling effciciency decreases for dust particles of 40 µm
and up. Moreover, the sampling efficiency depends on wind speed
and type of dust (wet or dry).
Since the early eighties, High Volume Samplers were often provided
of a PM10-inlet, thus avoiding the efficiency biases for large particles.
In the nineties, more and more High Volume Samplers were replaced
by more convenient dust monitoring systems.
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For special studies, however, the High Volume Sampler still is useful because
of the large air volume sampled. For instance, when for chemical analysis
of rare components a large amount of dust is needed.