IEC 81346-2:2009

Defines object classes and associated letter codes for these classes to be used in reference designations. Applicable in all technical areas and may be applied at any position in a tree-like structure set up in accordance with IEC 61346-1

Extends the letter codes of the main classes for purposes or tasks of objects in accordance with IEC 61346-2. Applies to all disciplines, such as construction, process and electrical engineering, power generation and distribution, process engineering facilities, naval architecture and ocean engineering.

IEC 81346-2:2019 establishes classification schemes with defined object classes and their associated letter codes, and is primarily intended for use in reference designations and for designation of generic types. The classification schemes are applicable for objects in all technical disciplines and all branches of industry. IEC 81346-2:2019 has the status of a horizontal standard in accordance with IEC Guide 108. It is also intended for use by technical committees in preparation of publications related to reference designations in accordance with the principles laid down in IEC Guide 108. IEC 81346-2:2019 cancels and replaces the first edition published in 2009. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) The entry classes of the classification scheme have been defined to reflect the “inherent function” of the object classified; b) The classes are defined to align with the principles of ISO 22274 and ISO 704; c) A three-level classification scheme has been defined, which provides a greater flexibility for the designer in some technical fields; d) Classes are defined by their definition and provided with a preferred term. Examples are provided if needed; e) A separate classification scheme for spaces has been provided.