NF X10-102-3:2003 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 3 : nozzles and Venturi nozzles.
1995NF X10-102:1995 Measurement of fluid flow by means of pressure differential devices. Part 1 : orifice plates, nozzles and venturi tubes inserted in circular cross-section conduits running full.