(a) If a rule document has an associated graphic as defined in §91.2 of this title (relating to Definitions), name the rule graphic file as follows: aa_bbbb_cccc-x."file extension." In this scheme, aa denotes the title number, bbbb denotes the chapter number, cccc denotes the rule number, and x indicates the number of the graphic file (if there is more than one accompanying the rule). Example: 01_0091_0001-3.html indicates this is the third file submitted for