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An official website of the United States government
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Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

* PHIN VADS usage tip: On the “View" page in PHIN VADS, “View Version Description” outlines guide version and updates as applicable. You can also navigate to previous versions or subscribe to future updates.