An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

National Service Center for Environmental Publications

How to Search for Publications Using Advanced Search

The Advanced Search tool in the National Service Center for Environmental Publications (NSCEP) allows you to control the breadth or narrowness of your search by specifying how the key words you provide are used and the relationships between them.  You can control how aggressive the search needs to be in matching your terms and where those terms should be applied.  As with the other searches, you can limit which publication date ranges to include in the search.  

Another function of Advanced Search is to provide options on how the system will present what it finds.  You can control how many matching documents to present at one viewing and how they are to be sorted.  When you choose a document to examine more closely, what page you want to see first and how that document is to be displayed.

You should be aware that what you enter in the search text box will depend on how you intend to search the repository.

What to look for: Enter your search terms and controls or phrases that describe your concept.  

How to look for it: Lets you tell the search engine how to look for your search terms.  All of the searches produce a result list of documents matching the search criteria.  The first four of these flavors will be affected by the use of Stop Words, so be careful what you enter.
(Learn more about stop words in searches.)

There are five different modes of search offered:

  1. cloud search - is a special case of the "all words" search.  This variant does not automatically display the result list.  Instead, the number of documents found is reported.  The resulting documents provide the seeds for a word cloud that can be used to assist in reducing the results list to a more manageable size, making this a form of progressive search.
  2. boolean operators – Allows you to enter your own combination of terms in the search box using AND, OR, and NOT as well as other controls available as part of the syntax native to the search engine.   Words entered in this mode that are not separated by some form of operator must appear together and in order in a document for it to qualify for the results list.  This search mode will usually offer the most powerful and precise results.
  3. all words - search for multiple terms.  Every word entered must appear somewhere in the text.  Unlike the boolean search, word order is irrelevant and each word is treated individually.  This will mean that the more terms you add to the list, the smaller the set of resulting documents offered will be.
  4. any words – search for documents with any of the search terms.  This will mean that the more terms you add, the larger the number of resulting matches will be.  This flavor of search is similar to using the boolean OR operator in a native search and is most useful when you need to search for various synonyms.
    Example: regulation rule ordinance
  5. exact phrase – search for multiple terms in exact order given.  This is the only search that ignores the substance of any stop word or command word entered, treating it only as a place holder in the phrase.
    • Example: wind farms are producing energy ("are" is a stop word that will be ignored - results will contain the other words in order with a stop word between "farms" and "producing")

Results precision (fuzziness): Allows you to search for variations of a word, including plural forms of nouns and different tenses of verbs. Select up to a four character difference.

Example: pollut searches for: pollution, pollute, pollutants…  but you will want to understand what a "fuzzy" search really means...

Select the dates to search: Limit the search to a set range of publication dates.

Control which page will be viewed first: Selecting the first page found with matching search keyword(s) allows you to quickly navigate to the pages on which your search term(s) appear(s).