1. n. [Drilling Fluids]

A test to measure static filtration behavior of water mud at ambient (room) temperature and 100-psi differential pressure, usually performed according to specifications set by API, using a static filter press. The filter medium is filter paper with 7.1 sq. in. filtering area. A half-size cell is sometimes used, in which case the filtrate volume is doubled.

Synonyms: API fluid-loss test,  static filter press

Antonyms: high-pressure, high-temperature filtration test

See related terms: filtercake,  filter medium,  filter press,  filter-cake quality,  filter-cake thickness,  filtrate,  filtrate tracer,  filtrate volume,  filtration,  fluid-loss control,  fluid-loss-control material,  relative filtrate volume,  spurt loss,  static filtration