For each category of works set out below, DEFKON T.S.A. (A.T.E.) holds a certification (M.E.E.P. Reg. No.: 20589) of the respective class:
| BUILDING CONSTRUCTION WORKS | 3rd class |
| ROAD CONSTRUCTION WORKS | 3rd class |
| PORT CONSTRUCTION WORKS | 3rd class |
| HYDRAULIC WORKS | 3rd class |
| INDUSTRIAL/ENERGY-RELATED WORKS | 2nd class |
| ELECTRICAL-MECHANICAL WORKS | 2nd class |
