dust fraction

The Neptunian rings contain a large quantity of micrometer-sized dust: the dust fraction by cross-section area is between 20% and 70%.

The two dust fractions are weighed and reported separately, as well as the total dust collected, all being expressed in grams per kilogram.

Nuisance, inhalable and respirable dust fractions are all sampled using a constant volumetric pump for a specific sampling period.

In analogy, the inhalable dust fraction is the fraction of dust entering nose and mouth which may be deposited anywhere in the respiratory tract.

The respirable dust fraction is dust that enters the 'deep lung' and is considered to be less than 10 micrometers AED.

A series of samples were obtained using the membrane filter method employing a variety of sample techniques, including personal and para-occupational sampling for respirable and inspirable dust fractions.

Ultra-fine dust fractions that pass through the measuring gas filter may give the impression of low contents of gaseous fluorine compounds in rotary kiln systems of the cement industry.