Abstract: A method for removing an insulating fluid containing polychlorinated biphenyl (PCB) which was used as an insulating medium, from the pores of a porous solid electrical insulating part which had been immersed in PCB-containing insulating fluid of an electrical apparatus from the group consisting of electrical transformers, chokes and capacitors includes the steps of removing the insulating part from the electrical apparatus and subsequently immersing the insulating part in a bath containing at least one fluid solvent for PCB selected from the group consisting of aliphatic, aromatic, chlorinated and fluorinated hydrocarbons. The insulating part is moved within the bath for a period of from 8-60 minutes at a speed of from 0.02 to 0.5 meters per second, and the solvent of the bath is heated during the movement of the insulating part from the ambient temperature to a final temperature of from 5.degree. to 25.degree. C. below the boiling temperature of the solvent at the pressure prevailing in the bath.