1 Scope
This standard specifies definitions and series of DN (nominal size).
This Standard is applicable to pipework components specified in relevant standards which use DN designation system.
Note: Other methods of size designation are also used, e.g. products having threaded, compression, solder or welded end connections or products designated by NPS (nominal pipe size), OD (outside diameter), ID (inside diameter), but these are not defined in this International Standard.
