What is ANSI?
The American National Standards Institute (ANSI) is a privately funded federation of business and industry, standards developers, trade associations, labor unions, professional societies, consumers, academia, and government agencies.  ANSI does not itself write standards.  ANSI is the United States member of ISO.

Is ASME Accredited by ANSI?
ASME is an accredited Standards Developing Organization that meets the due process requirements of the American National Standards Institute (ANSI).  Codes and Standards that are developed under an accredited program may be designated as American National Standards.