ISO/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.
The recently updated edition of the standard (ISO/IEC 81346:2019) is the result of extensive work by IEC and ISO to update the standard to make it applicable in a broader set of industries, and to provide users with the option of applying more detailed classification when creating reference designations.
The updated and new classification schemes are now based on the rules given in ISO 704, which means that the classification now consists of clearly defined classes of objects that provide a 100% stable classification through the entire object life-cycle.
We believe the new edition is very useful, and therefore would like to introduce you to part of it in brief here.
Entry classes
The classification scheme for technical objects has 17 entry classes in total, identified by the following letter codes:
Changes to the standard
RDS/81346 deals with systems and their relations. The output from 81346 is a reference designation which designates systems and their elements. There are three kind of relations to be used: Part-of relations (see 81346-1), Type-of relation (see 81346-2, 2019 edition) and pragmatic relations (to handle non-hierarchal relations for example for interface among systems).
In relation to the update of 81346-2, it became clear that the classification provided needed an update with new definitions following rules from ISO 704 and sub-classes controlled by type-of relations.
The differences between the 2009 and 2019 editions are shown below:
ISO/IEC 81346-2: 2009 edition | NEW ISO/IEC 81346-2: 2019 edition |
---|---|
Interdisciplinary | Interdisciplinary (expanded) |
Two-letter classification | Three-letter classification |
Implemented in object libraries | Stability for object libraries |
Type-of relations not clear | Type-of relations 100% perfect |
Backwards compability to 1996 edition | Backwards compability to 2009 edition |
Entry class: Intended purpose or task (unstable) | Entry class: Inherent function (stable) |
Definitions missing or unclear | Definitions for all classes implemented |
Class codes
With the 2019 edition it is now possible to distinguish between a door and a window, but also between a temperature transmitter and a temperature switch and so on.
Class code | Class definition | Class name (preferred term) |
||
---|---|---|---|---|
Q | object for controlling access or flow | controlling object | ||
controlling object to a space | space access object | |||
QQC | space access object for upright passage by persons | door |
Inclusion of alternative industry terms
The new edition is backwards compatible with the 2009 edition but now with crystal clear definitions of each class. This has also opened the possibility to include a range of different terms from any industry to be assigned to the updated classification in 81346-2, as the examples of terms with GPA shows below.
Class code | Class definition | Class name (preferred term) | Examples of terms | ||
---|---|---|---|---|---|
G | object for providing a controllable flow | generating object | |||
GP | object for providing a controllable flow of liquid | liquid flow generating object | |||
GPA | object for providing a controllable flow of liquid by forcing trapped liquid to the discharge side | positive displacement pump | peristaltic pump, piston pump, rotary gear pump, screw pump, vacuum pump |