Add at the end of the sentence of the 3rd paragraph: and overvoltage category III. Add after the 3rd paragraph the following note: NOTE 1 Additional requirements are necessary for circuit-breakers used in locations having more severe overvoltage conditions. Replace the 5th paragraph with the following: Circuit-breakers in compliance with this document are suitable for use in TN and TT system. Under specific conditions, circuit-breakers of this document are also suitable for use in IT systems, provided, that the requirements of HD 60364-4-43:2010 are complied with. Add after the 11th paragraph the following new paragraph: Supplementary requirements can be necessary for circuit-breakers of the screw-in types. Renumber Note as Note 2 Add after new Note 2 the following new Note 3: NOTE 3 Recommendations for the dimensional coordination between enclosures and circuit breakers for mounting on rails according to EN 60715 or equivalent means are given in the CENELEC report PD CLC/TR 50473.