NIH has adopted AIA layer naming conventions. The AIA CAD Layer Guidelines, U.S. National CAD Standard Version 2.0 contains the AIA master layer list that contractors must follow. NIH has developed electronic templates with the most common layers for each discipline (see Section 5.0 Files for Download). The templates are available at http://qualtrax.od.nih.gov/ ORF Guidance Document, Architectural and Engineering Standards.

Layer names consist of four defined field groups: Discipline Designator, Major Group, two Minor Groups, and Status. The Discipline Designator and Major Group are mandatory. The Minor Groups and Status fields are optional. Each field is separated from adjacent fields by a dash (“-“) for clarity.

A one or two character discipline designator followed by a four-character major group designator indicating the building system. Two four-character minor group designators may be added to further define the major group. Lastly an optional one-character status designator can be used. For example, AD-WALL-FULL-TEXT-N would be the layer for full height architectural demo wall text not in contract. Refer to section 2.2.4 Sheet File Designators for Level one and Level 2 Discipline Designators.

The AIA master layer list allows different layer names for the same information such as A-COLS, I-COLS, and S-COLS. NIH does not allow the use of duplicate names preferring that the information be placed on the layer of the discipline responsible for the information. For example, columns should always be placed on the structural layer (S-COLS), lighting should always be placed on the electrical layer (E-LITE), and plumbing fixtures should always be placed on the plumbing layer (P-FIXT). Additional layers may be may be required for specified projects.