An electric pole unit for a switching apparatus comprising: - a main body including: - a current breaking unit positioned in the internal volume of said electric pole unit; - first and second pole terminals (3, 4) electrically connected to said current breaking unit; - an insulating housing made of a rigid electrically insulating material and enclosing said breaking unit and said first and second pole terminals (3, 4), said insulating housing comprising first and second housing ports (51, 52) at said first and second pole terminals (3, 4), respectively, and first and second housing portions (53, 54) defining said first and second housing ports, respectively; - a first pole contact arm and a second pole contact arm fixed to said main body and electrically connecting said first pole terminal with corresponding first conductor and said second pole terminal with a second line conductor, respectively; wherein each pole contact arm (10A, 10B) comprises: - a conductor element having a first contact arm terminal and a second contact arm terminal, said first contact arm terminal being coupled with a corresponding pole terminal (3, 4), said second contact arm terminal being couplable to a corresponding line conductor of an electric line; characterised in that each pole contact arm further comprises - an insulating bushing made of elastically deformable electrically insulating material and enclosing said conductor element and comprising a first contact arm port and a first bushing portion defining said first contact arm port, said first bushing portion being coupled with a corresponding housing portion (53, 54) of said insulating housing and a corresponding pole terminal (3, 4); wherein the housing portions (53, 54) and the pole terminals (3, 4) of said main body are coupled with mechanical interference to the bushing portions of said pole contact arms (10A, 10B), thereby causing a deformation of said bushing portions (53, 54) and ensuring a dielectric sealing of mechanical junctions between said pole contact arms (10A, 10B) and said insulating housing. - a main body including: - a current breaking unit positioned in the internal volume of said electric pole unit; - first and second pole terminals (3, 4) electrically connected to said current breaking unit; - an insulating housing made of a rigid electrically insulating material and enclosing said breaking unit and said first and second pole terminals (3, 4), said insulating housing comprising first and second housing ports (51, 52) at said first and second pole terminals (3, 4), respectively, and first and second housing portions (53, 54) defining said first and second housing ports, respectively; - a first pole contact arm and a second pole contact arm fixed to said main body and electrically connecting said first pole terminal with corresponding first conductor and said second pole terminal with a second line conductor, respectively; wherein each pole contact arm (10A, 10B) comprises: - a conductor element having a first contact arm terminal and a second contact arm terminal, said first contact arm terminal being coupled with a corresponding pole terminal (3, 4), said second contact arm terminal being couplable to a corresponding line conductor of an electric line; characterised in that each pole contact arm further comprises - an insulating bushing made of elastically deformable electrically insulating material and enclosing said conductor element and comprising a first contact arm port and a first bushing portion defining said first contact arm port, said first bushing portion being coupled with a corresponding housing portion (53, 54) of said insulating housing and a corresponding pole terminal (3, 4); wherein the housing portions (53, 54) and the pole terminals (3, 4) of said main body are coupled with mechanical interference to the bushing portions of said pole contact arms (10A, 10B), thereby causing a deformation of said bushing portions (53, 54) and ensuring a dielectric sealing of mechanical junctions between said pole contact arms (10A, 10B) and said insulating housing. - a current breaking unit positioned in the internal volume of said electric pole unit; - first and second pole terminals (3, 4) electrically connected to said current breaking unit; - an insulating housing made of a rigid electrically insulating material and enclosing said breaking unit and said first and second pole terminals (3, 4), said insulating housing comprising first and second housing ports (51, 52) at said first and second pole terminals (3, 4), respectively, and first and second housing portions (53, 54) defining said first and second housing ports, respectively; - a first pole contact arm and a second pole contact arm fixed to said main body and electrically connecting said first pole terminal with corresponding first conductor and said second pole terminal with a second line conductor, respectively; - a conductor element having a first contact arm terminal and a second contact arm terminal, said first contact arm terminal being coupled with a corresponding pole terminal (3, 4), said second contact arm terminal being couplable to a corresponding line conductor of an electric line; characterised in that each pole contact arm further comprises - an insulating bushing made of elastically deformable electrically insulating material and enclosing said conductor element and comprising a first contact arm port and a first bushing portion defining said first contact arm port, said first bushing portion being coupled with a corresponding housing portion (53, 54) of said insulating housing and a corresponding pole terminal (3, 4);