TRACON Controller expressed concern regarding the failure of the facility to comply with agreed upon policies regarding certifications and authority to work positions reference traffic flows.

Narrative

I was made aware today that yesterday; a controller that is not 'certified' to work and East traffic operation; was working the West Sector. Background: when someone starts training in the subject area; they usually start on the West Sector. It is only a departure sector and one of our less complex in the area. They then normally progress to the harder sectors which includes arrivals. When this subject airport goes into East operation; the West Sector no longer is a departure sector but the main arrival sector for all air carriers landing in the area. There is a verbal agreement with management that a CPC will not work the West Sector during East operations as they have had no training on running arrivals. A controller was working the West Sector during East configuration and is only signed off on 2 sectors; none of which are arrival sectors. Also; this controller has had no live training on East operations other than a briefing during his West Sector classroom. This is extremely dangerous and contrary to what has been agreed upon with management. A CIC was on during this operation; followed by a FLM who continued letting the controller work. Recommendation; I recommend that there be a separate certification for East operations. At one time there was a policy to preclude this from happening. It was terminated a few years back when management verbally agreed not to use controllers on West Sector if they haven't had arrival training.