The purpose of this standard is to define the characteristics that shall be met and the tests that shall be passed by the accessories for the underground distribution network of electric energy transmission and distribution companies, with high voltage cables up to 18/30 (36 kV) according to the UNE HD 620. The accessories included in the scope of this standard are the following: unipolar joints; unipolar interior and exterior terminations. Mixed unipolar or three-polar joints between cables with dry insulation and cables with impregnated paper insulation are outside the scope of this standard.