Two cell libraries are used during i-model publishing, one for 2D and one for 3D.Default cell libraries are installed with the product and these can be customized by the user. The files are Sewer2D.cel and Sewer3D.cel, and can be found in the Bentley\SewerGEMS8 directory.

If no cell library is found, default cells are used (e.g. a circle in 2D and a sphere in 3D).