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'''Specific advice''':

There are many different types of handpumps. However most of them are positive displacement pumps and have reciprocating pistons or plungers. There are suction pumps, low lift pumps, direct action pumps, intermediate life pumps, and high lift pumps. For details on these types, look them up in [http://www.wateraid.org/uk/what_we_do/sustainable_technologies/technology_notes/244.asp Technology notes: Handpumps] (by WaterAid).