Defines requirements for protective provisions against the effects of stray currents resulting from operating d.c. traction systems. Applicable to all metallic fixed installations forming part of the traction systems, and to any other unrelated metallic components located in any position in the earth, which may carry stray currents as a result of the railway system operation. Applicable to all new electrification of a d.c. railway system, and may also apply to existing electrified systems where the effects of stray currents are considered.