简介:2.1 For liquid samples (i.e., those containing less than 0.5 % dry
solid material), the sample, after filtration through a 0.6 to 0.8 µm glass fiber
filter, is defined as the 1312 extract.
2.2 For samples contai简介:2.1 For liquid samples (i.e., those containing less than 0.5 % dry
solid material), the sample, after filtration through a 0.6 to 0.8 µm glass fiber
filter, is defined as the 1312 extract.
2.2 For samples containing greater than 0.5 % solids, the liquid phase,
if any, is separated from the solid phase and stored for later analysis; the
particle size of the solid phase is reduced, if necessary. The solid phase is
extracted with an amount of extraction fluid equal to 20 times the weight of the
solid phase. The extraction fluid employed is a function of the region of the
country where the sample site is located if the sample is a soil. If the sample
is a waste or wastewater, the extraction fluid employed is a pH 4.2 solution.
A special extractor vessel is used when testing for volatile analytes (see Table
1 for a list of volatile compounds). Following extraction, the liquid extract
is separated from the solid phase by filtration through a 0.6 to 0.8 µm glass
fiber filter.
2.3 If compatible (i.e., multiple phases will not form on combination),
the initial liquid phase of the waste is added to the liquid extract, and these
are analyzed together. If incompatible, the liquids are analyzed separately and
the results are mathematically combined to yield a volume-weighted average
concentration.详细>