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National Service Center for Environmental Publications

Search Stop Words in the National Service Center for Environmental Publications

In all instances, be careful to avoid common words, referred to as "stop" words. The system will not prevent their use in a query but will generate an error message if they are not removed.

When you remove a "stop" word, you will need to add an "and" in place of the removed "stop" word. This will let the database search the field properly. If you do not add the "and" in place of the "stop" word you removed, you will get a ‘No documents found’ result. For example, if you are searching for the title: Compilation of Air Pollutant Emission Factors", you would type in the title field: "Compilation and Air Pollutant Emission Factors". 

In addition to the list below, single alphabet characters are also considered stop words but numbers are not.

NSCEP Search Stop Words
A-B C-G H-L M-O O-S T-U V-Z
a came had made of take very
about can has make on takes was
after come have makes only than way
all comes He many or that we
also could her me other the well
an did here might others their were
and do hers more our them what
another does him most ours then when
any each himself much out there where
are eol his must over these which
as eos how my said they while
at for If never same this who
be from in not see those with
because get into now sees through would
been got is   she to you
before   it   should too your
being   its   since under yours
between   just   so up  
both   like   some    
but   likes   still    
by       such