Configuration > System Configuration > Dimension styles
  
Dimension styles
When you activate the option Default settings in the Dialog box ATHENA options, ATHENA loads the dimension styles in new drawings from the file ATHENA\DATALOCAL\ath_dim.dex. This is the library file containing the dimension styles.
As standard, metric (mm) and British (inch) dimension styles are provided. Which is displayed depends on the current setting for the drawing units.
The ASCII files with the file extension *.dim from earlier ATHENA versions are no longer used. For reasons of compatibility though they are converted during the program start into an ath_dim.dex if the file ath_dim.dex has not been found.
Note 
If ATHENA is installed in a network, you can move the library file ath_dim.dex into the DATAGROUP folder to ensure that all ATHENA users in the network use the same dimension styles.
Use the AutoCAD command _dimstyle to create and change dimension styles. You will find further information in the AutoCAD documentation.
Use the command Manage dimension styles to manage dimension styles of the drawing or of the library.