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Capsule- and disk-filter procedure

March 1, 2016

Capsule and disk filters are disposable, self-contained units composed of a pleated or woven filter medium encased in a polypropylene or other plastic housing that can be connected inline to a sample-delivery system (such as a submersible or peristaltic pump) that generates sufficient pressure (positive or negative) to force water through the filter. Filter media are available in several pore sizes, but 0.45 µm is the pore size used routinely for most studies at this time. Capsule or disk filters (table 5.2.1.A.1) are required routinely for most studies when filtering samples for trace-element analyses and are recommended when filtering samples for major-ion or other inorganic-constituent analyses.

Publication Year 2016
Title Capsule- and disk-filter procedure
DOI 10.3133/twri9A55.2.1.A
Authors Stanley C. Skrobialowski
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Techniques of Water-Resources Investigations
Series Number 9-A5
Index ID twri9A55.2.1.A
Record Source USGS Publications Warehouse
USGS Organization Office of Water Quality