Van Dorn sampler

Sample collection varies from hand sampling procedures at a single point to more sophisticated multipoint sampling techniques, such as the equal discharge increment (EDI) method or equal transit rate (ETR) method. Different types of water samplers can be used to collect water samples from bodies such as rivers, seas, lakes, etc. The Blumer sampler [30], Deutsche Hydrographisches Institute sampler (DHI) [31], and a high volume water sampler, designed to pump water from a defined depth below the water body surface outside the wake of the survey vessel, are suitable as samplers [32], The Kemmerer and van Dorn samplers may also be used for water sample collection. For rivers, up- and downstream samples are usually required, as well as the points where tributaries or waste drains join the main stream under study. 

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