design stage
In Bentley civil products, corridor design stages have a significant impact on the type and accuracy of data exported in an i-model (.icm.dgn). Design stages and associated settings are typically part of a company’s libraries, and vary depending on the standards the company wishes to use. Individual DGN files will only contain the stages (and feature definitions) used in their particular project. Each corridor in a DGN file may have an independent design stage setting.