About Portable Document Format (PDF) Files


HTML (the code behind Web pages) cannot maintain all the original formatting and presentation of many documents. In such cases, we use a different format: Portable Document Format (PDF). PDF documents maintain the look of the original document, and they can be viewed on any Macintosh, PC, or Unix computer. First, however, you must download and install a PDF reader program.

Installing Adobe Reader

The Adobe Reader Web site Exit AIRNow contains detailed information on this product, and allows you to download free copies of Adobe Reader for Windows, Macintosh, or UNIX systems. Please note that there are other PDF viewers you can use instead.

We suggest that you configure Adobe Reader as a plug-in application for your Web browser. You won't have to wait for a separate application to launch; you can read PDFs directly in your browser. You can start reading the PDF file while it's still downloading. You can also read PDF pages side by side.

If you already have a Web browser installed on your computer when you install Adobe Reader, it should automatically install itself as a browser plug-in. You will know that it is properly installed as a helper application if you see the PDF file in the browser window, with a row of special Reader buttons along the top of the viewing screen.

Downloading Large Adobe PDF Files

Download times of large PDF files vary based on connection speed. If a document is labeled with a megabyte, it should be considered a large file and it may take a while to download to your PC. At EPA, PDF file sizes are labeled and megabytes are indicated by MB.

Printing Adobe PDF Files

When printing Adobe PDF files from within your web browser, do NOT use the web browser print facility. Instead, use the print button at the left end of the special Adobe Reader tool bar, which appears immediately above the viewing window. See illustration below for location of this print button.

Accessibility of Adobe PDF Files

Visit http://www.adobe.com/accessibility.html Exit AIRNow for more information on how to make PDF files more accessible to people with disabilities.


Adobe®, Reader®, and Adobe Type Manager® are registered trademarks of Adobe Systems Incorporated in the United States and/or other countries. © Copyright Adobe Systems Incorporated. All rights reserved.


The preceding links are not located on the EPA Web site but are provided to help you find tools and information you may need to read content from the EPA Web site. These links do not represent an endorsement of the products or any commercial enterprise.

This page was last updated on Thursday, May 22, 2014.