I am registered both in Virginia and Arkansas.  Arkansas requires 15 PDH's per year (Professional Development Hour) I have been completing this requirement for some 8 to 10 years.  They are flexible in their requirements and include reasonable items to which most engineers would be exposed.  Please note their concept. 

PDH- Contact hour of instruction or presentation; CEU= 10 PDH's; Includes active participation in professional or technical societies; Patents;  Authoring published papers, articles, books; Teaching or instructing in college courses, continuing education courses or presenting or attending qualifying seminars, in house courses, workshops, or professional or technical presentations made at meetings , conventions, or conferences.

The have build different PDH into what ever exposure you may have had, i.e.: 2 PDH's for active participation in professional and technical societies (each organization) 1 PDH for each hour of professional development at seminars professional or technical presentations; 45 PDH's for 1 college or unit semester hour of credit received.; 10 PDH's for each published paper, article or book.

These are presented ideas that would probably occur within the course of an engineer's normal work and are not overly onerous to accomplish.