About PDF Files
Files identified as "PDF" or "Adobe Acrobat" are in the Portable Document Format developed by Adobe Systems, Inc. PDF files can be viewed with any of the programs listed at right and printed with most of them. This list may not be comprehensive. (These and other links to external websites will open in a new browser window by default.)
Most of the PDF documents on this website are in PDF versions 1.4 through 1.6. The following table shows PDF versions and the corresponding minimum version of Adobe Reader required. For the other software listed at the right, you will need to check the documentation of the software to see which versions are required to read each PDF version.
In most cases, a PDF document will appear on screen and print exactly like the original document. However, due to variations in your installed fonts, computer display and printer drivers, parts of a document (especially equations and special characters) may not appear or print correctly. For this reason, the PDF version of regulations or other official documents are not considered the official version.
With some versions of web browsers and readers, a PDF document may not appear when you click on the link. If you encounter that problem, try this: