When you save a CATIA file, a log file of the conversion is created:
The log file for conversion to CATIA® lists the conversion parameters and information about the entities converted in the process.
In the log file you find:
Convert Surface to NURBS by using tolerance value: 0.001000 Conversion successfully completed. The solid #66 is manifold at tolerance 0.010000 Conversion successfully completed. The solid #314 is manifold at tolerance 0.010000 Conversion successfully completed. The solid #419 is manifold at tolerance 0.010000 Conversion successfully completed. The solid #548 is manifold at tolerance 0.010000 Conversion successfully completed. The solid #653 is manifold at tolerance 0.010000 Conversion successfully completed. The solid #824 is manifold at tolerance 0.010000 Number of entities not processed All entities have been processed Number of entities processed ARC :2 SOLID :6 List of entities moved to a different layer No entity in layers higher than 255 List of CATIA converted entities 340 CURVE(S) 84 SURFACE(S) 84 FACE(S) 6 VOLUME(S) 2 CIRCLE(S) Code Page used : Index size: 28432 Data size: 202184 Model Size: 999.999978 Tolerance for identical curves: 0.010000