IFATCA Policy is:

Remuneration for air traffic controllers should recognize the uniqueness of the Air Traffic Control profession and the associated responsibilities.

Remuneration of air traffic controllers should reflect their “employment status” in accordance with ILO Publication ISCO-08, in which air traffic controllers have been put in a category that includes Aircraft pilots, ships’ officers and other related “associate professionals”.

(See: https://www.ilo.org/public/english/bureau/stat/isco/docs/publication08.pdf)

Remuneration should be commensurate with acquired levels of skill and experience. The remuneration of controllers should therefore reflect their skills and also have relation to the acquired amount / type of ratings.

When a controller is assigned additional tasks, such as instruction or system- development, this should also be reflected by a higher remuneration level.