The U.S. National Institute of Standards and Technology issued a document entitled “Framework for Improving Critical Infrastructure Cybersecurity” dated February 12, 2014. This document is now being used by FDA as a reference in its cybersecurity program. You can download version 1.0 here: Framework for Improving Critical Infrastructure Cybersecurity Version 1.0
See our later post on the version 1.1. update: Framework for Improving Critical Infrastructure Cybersecurity Version 1.1