Sampling shallow-water samplers

A manually operated piston sampler (Figure B.16) consists of a metal tube (length 2 m) in which a piston with rubber sealing perfectly fits (diameter 50 mm). Because of combined action of creating a vacuum while raising the piston and simple manpower, a hollow metal tube can be pushed into the subsoil over a distance of 2.0 m in loose/soft sediment. A disturbed sample with a penetration depth of 2.0 metres is retrieved. In a marine environment, (2) divers operate the piston sampler. It is often used for small sand searches (<1,000,000 m ) in shallow water depths (<25 m). 

EN ISO 28265 Water quality - Methods of biological sampling - Guidance on the design and use of quantitative samplers for benthic macro-invertebrates on stony substrata in shallow freshwaters (ISO 8265 1988) 1994 Under revision... 

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