The following FAQ is designed to answer your questions about our PDFs.

If you have additional questions, please contact Customer Service.

Sharing National Academies Press PDF files:
About the PDF Files Offered at NAP:
Downloading PDFs:

Sharing National Academies Press PDF files

May I share my PDF with others?

All of the National Academies Press books (electronic and printed versions) on this website are copyrighted by the National Academy of Sciences with all rights reserved. You may not distribute, post, or copy our work without written permission from the National Academies Press. Posting or distributing our PDF files not only violates our copyright but it also could proliferate the sharing of non-authoritative versions of our reports.

We encourage sharing our books via approved means to help to maximize the impact of our work. Please use the following methods to ensure that everyone receives up-to-date, authoritative files directly from the National Academies Press servers.

  • Point your colleagues to the book's unique URL indicated above. Example: www.nap.edu/catalog/12614.html. Each book will have a different number before the .html extension.
  • Use the widget on the book's catalog page for embedding on your Website. The widget will allow people to download the PDF for free without leaving your site but will pull the file from our servers, ensuring an authoritative version.
  • Click the share buttonshare button demo on the book's catalog page to conveniently access the tools to tell your colleagues about the book and point to its free PDF file.
  • Connect the book with your friends and colleagues via Facebook Facebook button demo and Twitter buttons twitter button demo found on the book's catalog page.

Please see our Terms of Use for additional information.

For all other copyright inquiries, more information is available on our Rights & Permissions page.

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About the PDF Files Offered at NAP

Are all books available in PDF format?

The National Academies Press is proud to be one of the only online bookstores that provides anyone in the connected world with free page-by-page access to all of our books. We began doing this in 1996.

As of June 1st 2011, PDFs of reports that were previously for sale on the National Academy Press (NAP) website and PDFs associated with future reports will be offered free of charge to all Web visitors.

There are a small number of older reports that never had PDF files and therefore, those reports are not available for download. In addition, there are contractual requirements that preclude NAP from offering some PDF files for free. Those include the series "Nutrient Requirements of Domestic Animals" and books in the Joseph Henry Press imprint. Reports from the Transportation Research Board are available in various formats on their site, www.trb.org.

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Downloading PDFs

How do I download PDF files?

You may download PDF files from the National Academies Press either by A) creating an account or B) as a guest.

Creating an Account

To create an account either click here or on the Register link on the top right of any page on our site.

You can also create an account by clicking the Download Free PDF button on any book page and then selecting the Create an Account button.

Downloading as a Guest

To download a PDF as a guest, click on the Download Free PDF button on any book page, then select Continue as Guest.

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What is a PDF file?

PDF is an acronym for Portable Document Format. The PDF file is designed to look the same on the screen and in print, regardless of what kind of computer or printer someone is using and regardless of what software package was originally used to create it. Although they contain the complete formatting of the original document, including fonts and images, PDF files are highly compressed, allowing complex information to be downloaded efficiently.

What software do I need to read a PDF?

Almost all modern operating systems will have a default program for opening up PDFs, such as Preview on Macs, that will open the file when you double-click on it. Additionally, most modern web browsers are capable of viewing PDFs, so you can drag and drop a PDF into the browser to read it.

If neither your operating system or your browser is capable of opening PDFs, you can download Adobe Reader here, which will allow you to open and read PDFs.

How long will it take for me to download a PDF file from your Web site?

The time it will take you to download our PDF files depends on the type of connection you have and the size of the book. The following table provides estimated times.

Estimated time to download the average chapter:
28.8K about 3-4 mins/chapter
56 K about 2 mins/chapter
T1/Cable/DSL about < 1 minute/chapter

Estimated time to download the average book:
28.8K About 30 minutes
56K About 15 minutes
T1/Cable/DSL < 3 minutes

What's the best strategy if I'm on a very slow, bad line?

Try downloading individual chapters (instead of the entire book), or start the whole-book download at the end of the day, before you go to sleep, and let it download overnight.

When I download files, where on my computer will they be saved?

While different browsers may have different default locations for the files downloaded from that browser, most modern browsers will save the file in a folder called Downloads. If you're unclear about where the files are being saved, look in the settings of your browser for the default download location.

On iPhones and iPads, choosing to download the PDF will only open the PDF in a browser window, but will not save it automatically. Once the PDF has loaded in the browser window, tap somewhere in the page and you will see a button that says "Open In" in the top right on the iPad and the top left on the iPhone. Tap that button, and that will allow you to save the PDF to iBooks or any other app that will allow you to read PDFs, such as Amazon Kindle or Dropbox.

How do I view or print my downloaded files?

To view or print your downloaded files, you must have a PDF reader such as Adobe Reader or Mac Preview loaded on your computer. In Windows Explorer, Mac Finder or other file management program, locate the drive and folder where you downloaded your files and double click on the filename. At that point, your default PDF-reading program will open and display your PDF file for viewing. To print the file, use the printing function in the application.

Why are some PDF files on your site searchable and others are not?

The majority of the PDF files on our site are fully searchable. They are called "native" PDF files and are created from source files. A few of the PDF files are created from pictures of the pages, and are called "scanned image" PDF files. These are very large and are not searchable. We create this type of PDF when no source files are available.

Still have questions?

Contact customer service and we'll be happy to help you.

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