Hazards & Safety

Environmental Contaminants Encyclopedia

How to use this product

I. How to Use:

First review the topics covered in this product by looking over the topics and file names in Entries, Filenames.

Next, try searching for information in the encyclopedia by clicking on the "Search Engine" choice on the Contaminants Encyclopedia Index Page.

No matter what kind of browser is being used (even Microsoft Internet Explorer), the "Netscape Search Engine" page will open. Do not enable either the "match case" or the "match whole word" options. Try a simple search first by typing in the word "Irwin" and clicking on the "search" button. Since Irwin is the senior author's last name, the search will bring up all 120 encyclopedia files. Since all the files are Adobe Acrobat PDF files, the extension on the end of all files will be ".pdf" target="_blank". The first part of the file reflects the file subject, so the "mercury.pdf" target="_blank" file is an Adobe Acrobat file summarizing information of mercury.

Next try clicking on any of the 120 PDF files. If the file comes up normally and can be read immediately, it means that some version of Adobe Acrobat Reader is already installed on the local drive (usually a hard drive) being used, and that the browser (Netscape, MS Explorer, America Online/AOL, etc.) setup has already been modified to choose Acrobat Reader (either as a plug-in working within the browser or as a Helper Application launched separately) for reading Adobe Acrobat (*.pdf) files. If the file came up normally, everything is already working! Skip the next paragraph and continue reading down the list of tasks.

If the browser did not open the file normally, but instead something else happened, like:

• Some sort of "download" message appeared, or
• A message like "no helper application is defined" appeared,

skip the rest of this list for now and move down to item II (Install Reader) below.

Once a PDF file is open on the internet browser in use:

1. First single click on the "bookmark" button (usually third from the left on the upper tool bar in internet versions) to bring up a split screen showing the bookmarks, and then
2. Move down the list of bookmarks on the narrow split screen to the left and single click on each bookmark in turn to move through and become familiar with the major headings. The same procedure may be used to bring up bookmarks in any of the PDF files provided herein.

   Note: The bookmark button always has text to the right and bullets with lines to the left. On certain (not all) computer/browser/ISP combinations, the bookmarks take a while to load the first time the bookmark button is clicked. In subsequent uses, the conversion is much faster.

The other way to search for information once an Adobe Acrobat PDF file is open is to use "Acrobat Find" (click on the tool bar button with the stand-alone binoculars). For details, see "Organization of Each Entry" on the Contaminants Encyclopedia Index Page.

Now that the basics are covered, try searching the Contaminants Encyclopedia for words like mercury, selenium, trichloroethylene, alkanes, oil spills, petroleum, fuel oil number 6, jet fuel 4, and ethylbenzene, used motor oil, and vinyl chloride. Then try searching for combinations such as:

• Jet Fuel 4 and fate
• Diesel 2 and Fate

A faster way to open files: If Adobe Acrobat Reader is already installed on the local drive being used, a user can more quickly open any of the Contaminants Encyclopedia PDF files by typing the file name (see Entries, Filenames) after "/toxic/" at the end of the active URL. In other words, in the browser type in the URL "www.nature.nps.gov/toxic/referenc.pdf" target="_blank" to open the references file. References are documented as numbers within brackets, using the format of the Journal of Environmental Toxicology and Chemistry, with all references listed in numerical order in a separate file labeled "REFERENC.pdf" target="_blank"). In the same manner, use URL "www.nature.nps.gov/toxic/mercury.pdf" target="_blank" to open the mercury file. Opening files this way is not only faster, but the bookmarks seem to load faster after the PDF files have been opened this way. Do not capitalize .pdf, since some browsers do not work right if PDF is capitalized.

In open Adobe Acrobat files, if the "Hand" button is selected as the cursor (it toggles on and off on the tool bar), the user can push the page up and down by dragging the hand up and down the page. If the "ABC" button (the "Select Text" button) is selected instead of the hand button, the cursor can be used in normal Windows style as a cursor to highlight blocks of text. Blocks of text can then be copied and pasted into other windows documents.

More detail: A good source of information on how to search and move around in (an already open) PDF file being displayed by an internet browser is the Adobe Acrobat Readme file (typical location: c:\acrobat3\readme.wri). Some recent information from that source is repeated below for the convenience of the user:

"The following tools have been added to the Acrobat Toolbar displayed when viewing PDF files inside the Netscape Navigator or Microsoft Internet Explorer window:

• A "copy" tool, which appears to the left of the "hand" tool; it's icon shows two pages (a page and its copy).
  Note: this is active after text has been highlighted.
• A "select text" tool, which appears to the right of the "zoom out" (magnifying glass minus) tool; its icon shows the letters "abc" in a selection box
  Note: use to change the cursor and then highlight text.
• A "find" tool, which appears to the right of the "fit width" tool; its icon is a pair of binoculars
• A "find again" tool, which appears to the right of the "find" tool; its icon is a small pair of binoculars under a curved arrow
• When viewing PDF documents within a browser window...
  • To copy text (for pasting elsewhere):
    • click on the "select text" tool
    • select the desired text
    • click on the "copy" tool
    • when you are done selecting text, click on the "hand" button to return to browsing
  • To find a text string
    • click on the "find" tool
    • enter the desired text in the Find dialog
    • click on the Find dialog's "Find" button, or
    • click on the "find again" tool to find another occurrence of the text

      Note: Finding text may take a while if pages in the PDF file must be retrieved from the Web server. During the find operation the Find dialog's "Cancel" button will not function. The find operation can be stopped using the escape key

• Select, Copy, Find, and Find Again must be done using the tools on the Acrobat toolbar. The "Copy", "Select All", and "Find..." menu items on your browser's "Edit" menu will not invoke the corresponding command on PDF documents.
• In addition, Acrobat 3.01 enables basic keyboard navigation when viewing PDF files in the browser window using Netscape Navigator and Microsoft Internet Explorer. You can use the Page Up, Page Down, Home, End, Enter, Return, and cursor keys as described in the Adobe Acrobat Reader 3.0 Online Guide (Reader.pdf). When using keyboard navigation while viewing a PDF document in Continuous or Continuous - Facing Pages modes, the document image may occasionally disappear. If this occurs you can use the toolbar navigation buttons to restore your image."

II. Install Reader:

If the PDF file could not be opened normally by the browser, and some sort of "download" link appeared, it probably means that a more recent (version 3.01 or later) Adobe Acrobat Reader is not already on the local drive being used. If this is the case, continue down this list of tasks. If instead Adobe Acrobat Reader is already installed on the local drive (a typical location might be C:\acroread for older version 2.1) or C:\acrobat3 for newer version 3.01) and some sort of "no helper application is defined" or "Choose Start Program" or "Unknown File Type" message appears rather than a download message, skip the next paragraph and move down to item III (Browser Setup) below.

In order to read the Contaminants Encyclopedia files on the internet, the user must have Adobe Acrobat Reader installed on the local drive in use (usually the hard drive). Many users who have substantial computer experience or who have used the Internet extensively will already have some version of Acrobat Reader on their computers. How to tell which version of Acrobat is already installed: look at the acrobat readme file:

• For Acrobat 3 or 3.01, the readme file will most likely be in the following path: c:\acrobat3\readme.wri
• For Acrobat 2.1 (replace this with "Reader with Search" version 3.01 if 2.1 is the only version available on the local drive being used), the readme file may be found in the following path: c:\acroread\help\readme_r.wri.

If you don't know whether or not Adobe Acrobat Reader is already on the computer being used, look through the hard drive and/or program files and see if Acrobat is already installed. If it is already installed, it will most often be in the root directory (again, under something like C:\acroread for older version 2.1 or under C:\acrobat3 for newer version 3 or 3.01) or in the program files (for example C:\program files\acrobat or C:\Program Files\Netscape\Navigator\Program\RS32E301.exe).

Windows 95 users who unsuccessfully tried to open a PDF file in Netscape Search (in Step one) may have gotten a download option. Click on "More Information" to go to the Plug-In Finder Page. Then click on the yellow button that says "Get Acrobat Reader." On the next page that appears, in the three option boxes, specify "Reader With Search (not just "Acrobat Reader"), specify your operating system (Win 95, Win 3.1, Mac, Unix, etc.) and specify the language (For example, English). At the bottom of the page, choose the download link (in the case of Windows 95, choose the download link "download RS32e301.exe." Try it again if the server was busy.

Those who do not already have Adobe Reader installed on a local drive can also download the latest free update of "Acrobat Reader with Search." from the Adobe Home Page. As of February 1998, free downloads and other information were available from the Adobe home page on the world wide web at www.adobe.com.

Once the Adobe Home Page is open, click on the yellow button that says "Get Acrobat Reader." On the next page that appears, in the three option boxes, specify "Reader With Search (not just "Acrobat Reader"), specify your operating system (Win 95, Win 3.1, Mac, Unix, etc.) and specify the language (For example, English).

Once Adobe Acrobat Reader 3.01 or higher is installed and functioning, read section III (immediately below):

III. Browser Setup and Browser Issues:

Installation of browser plug-ins and other browser setup details will often be automatic when newer versions (3.01 or later) of Adobe Acrobat Reader are installed on computers after an internet browser is already installed. So, if the user has just downloaded the latest Adobe Acrobat Reader with Search (version 3.01 or later), the PDF files will hopefully work just fine in the browser. However, when it comes to computers, we would never claim "nothing can go wrong!"

Viewing Adobe Acrobat PDF files over internet web browsers works best on newer software: Netscape 3.0 or newer, Microsoft Internet Explorer (MISE) 3.0, and Adobe Acrobat Reader 3.01 or newer. When viewing PDF documents within a Netscape Navigator or Microsoft Internet Explorer window, Acrobat v. 3.01 adds some new functionality.

So, if you have not already installed the free Adobe Acrobat Reader 3.01 (or newer), go back to Install Reader (Item II, above) and do so. If you have to use an older browser, be sure to read the limitations and problems provided in the Adobe Acrobat Readme file (typical location: c:\acrobat3\readme.wri) or the Adobe Home Page (www.adobe.com).

Acrobat v. 3.0 does not fully support MSIE 4.0. Acrobat v. 3.01 is designed to work with MSIE versions 3.0, 3.01, 3.02, and 4.0. However, use of Acrobat v. 3.01 with MSIE 4.0 has not been extensively tested. MISE 4.0 users should consult the latest Adobe Readme File (typical location: c:\acrobat3\readme.wri) and MISE browser plug-in discussions (see www.netscape.com) for special instructions on optimum ways to view PDF files in MISE 4.0.

Some Windows 95 users, after having downloaded Adobe Acrobat, may still get a "Unknown File Type" message when trying to open a PDF file. In that case, choose "Pick Application", then pick "Browse", then "look in" a logical place to find Acrobat Reader. Logical options include:

• C:\Acrobat
• C:\Acrobat3
• C:\Program Files\Netscape\Navigator\Programs\RS32e301.exe

The RS32e301.exe file is an Acrobat Reader installation file.

Wherever it is found, click on RS32e301.exe. Then click on "open" and "OK". If not already installed, Adobe Acrobat with Search will install to c:\Acrobat3. Once Acrobat Reader is installed, for future use of the program, a short-cut can be placed on the desk top by dragging the "Acrord32.exe" file to the desk top (full path c:\acrobat3\reader\acrord32.exe).

In Windows 3.1, once the 16 bit "Acrobat Reader with Search" has been installed on the C: drive, the browser may still have be configured to choose the correct path to Acrobat Reader. If double clicking a PDF file brings up the message "You have selected a document with a content type of application /PDF. No helper application is defined for that type. Would you like to setup an application to present this type of document?" Click Yes. In the Select Application Box, click C:, then click on C:\Acrobat3\Read16\acrord16.exe. Next, click "OK." Then wait until it works to load the PDF file.

In a certain cases, Acrobat Reader may already be installed, but when double clicking on a PDF in an internet browser, an Adobe Acrobat window may open but the file may not open. If this happens in Netscape, check to be sure the Adobe Acrobat PDF plug-in file is installed in the proper place.

In Windows 95, a typical location for the PDF plug-in file (nppdf32.dll) is the following: c:\programs files\navigator\netscape\navigator\program\plugins\nppdf32.dll. In Windows 3.1, the path will be similar but the file name will be nppdf16.dll.

In trouble shooting potential Netscape problems, a user can also choose the "Options" pull down menu, then choose "Preferences", and then choose "Helpers." In the box, a path to the Acrobat Reader executable .exe file (for example, something like C:\Acrobat3\Reader\AcroRd32.exe) should appear (or try typing it into the box if absent).

If the Acrobat PDF files can be maximized to take up a full screen (except for the top browser tool bars), your browser is probably using Acrobat Reader as a plug-in. With a plug-in, the PDF file shows up in the browser itself much like a standard HTML page. When using PDF files in a browser, plug-in, no menus are visible, so use the buttons to navigate the file. The commands for find, find again, and copying to a clipboard may work differently in a browser plug-in than in a helper application. If problems are encountered in those functions, the user can always use the "Save as" function to save the file, then open the file on a local drive in Reader.

If the PDF window cannot easily be maximized to take up most of a full screen, Acrobat Reader may be working as a helper application. When working as a helper application, Adobe Acrobat is launched as a separate application.

Adobe Acrobat PDF files are used very broadly on the internet, and the Contaminants Encyclopedia PDF files opened normally in the Microsoft Internet Explorer and AOL/Excite browsers used during recent trials. To get the most out of the Contaminants Encyclopedia files as well as the many other PDF files on the internet, it is best to use a browser that supports Adobe Acrobat PDF plug-ins (such as Netscape 3 or later or Microsoft Internet Explorer 3 or later).

If all else fails, the Contaminants Encyclopedia PDF files can usually be downloaded one at a time by first using the provided search engine to find the file of interest and then right clicking on the PDF file name link. Once downloaded, the file can be opened utilizing an Adobe Acrobat reader installed on a local drive. This will allow the user to read the files one at a time, but the user will not be able to search through multiple files simultaneously unless they are using the internet search engine or the local drive Adobe Acrobat "Search" engine provided with CD-ROM versions of this product.

Library computers: The only major problems we encountered in trying to get Encyclopedia PDF files to open properly during trials were on public library machines which had been restricted by local staff to prevent downloads and other common functions. Some did not have the proper Acrobat plug-ins installed, and one was trying to run a 16 bit Acrobat Program on a 32 bit Windows 95 system. So if you are having trouble with browser setup at a public library or other public computer, talk to the system administrator to get the problems resolved so that PDF files can be viewed normally.

There are a large number of browser/computer/ISP setup possibilities. We didn't try opening the files over the internet with Mac or Unix or the many other non-windows operating systems and browsers to see how easily they utilize Adobe Acrobat. If problems are encountered, seek help from the home pages (and/or technical assistance lines) of the browser, soft ware, and/or ISP being used.

The Adobe Acrobat Home page (www.adobe.com) has links to technical assistance and answers to common questions. Included in one section is things to try if PDF files are not opening correctly.

For assistance from Netscape, first click on "Help" on the toolbar, then choose "About Plug-Ins." This will tell you which plug-ins are already installed. Information from Netscape may also be obtained from the Netscape home page ( www.netscape.com). If an Adobe Acrobat Plug-in needs to be installed or updated, choose Get Acrobat Reader from Adobe home page (www.adobe.com).

For assistance related to Microsoft Internet Explorer, look over the options at www.microsoft.com.

For other browsers, use the help lines provided by Adobe (www.adobe.com) and/or the browser being used. Again, since no software was independently developed for this project, technical questions related to software should be directed to the manufacturer of whatever software is being used to read the files, rather than to the National Park Service. Getting Adobe Acrobat Reader to work efficiently with your internet browser is a good thing to do anyway, because there are many PDF resources on the internet.

Once browser setup is complete, return to How to Use (section I above):