For the standards DIN ISO 1219-1 and ISO 1219-2 the following status applies:

- DIN ISO 1219-1:2006-10: withdrawn, replaced by ISO 1219-1: 2012-06
- DIN ISO 1219-2:1995-12: withdrawn, replaced by ISO 1219-2: 2012-09
The function of a component cannot be identified conclusively with the designation code of ISO 1219-2:2012-09. In the Festo Didactic documentation we select the following representation:
- The identification letters of products or the reference identifiers are being used in circuit diagrams according to EN 81346-2:2009-10 as of 2014.
- Component designation with two letters is used more frequently.
- The circuit symbols are displayed to ISO 1219-1:2012-06 and EN 60617-2:1997-08 to EN 60617-13:1994-01