[en] The heavy water cooled and moderated pressurized water reactor MZFR with a thermal power of 200 MW will be dismantled step-by-step within the framework of sectional decommissioning licenses. The past decommissioning step (6^th sectional license) in general covered the removal of the primary systems and of all reactor support systems inside the reactor building. The measures for radiation protection during dismantling and handling of the large components of the primary system, such as the fuel element loading machine, fuel element transfer system, steam generator and pressurizer shall be pointed out. The measures taken for the reduction of the dose rate during dismantling and cutting of the components for the purpose of conditioning or unrestricted reuse at the Central Decontamination Department (HDB) shall be described. Chemical decontamination of the primary circuit and its components, which had to be executed in order to reduce the dose rates for subsequent manual dismantling, shall be presented. The dismantling of parts of the fuel element transfer system, e.g. the highly activated components at the fuel transfer tube with dose rates up to 850 mSv/h had to be executed. Furthermore, it will be reported about the method of separating the heating area of the pressurizer as well as the technical execution of the transportation of the steam generators in one piece under the spatial conditions within the building. The efforts undertaken for the protection of individuals in view of the difficult radiological boundary conditions (high concentrations of tritium in all systems as well as very high alpha contamination of the fuel transfer system) will be explained. Moreover, dose-minimizing measures during cutting of the primary circuit and its components at HDB shall be described by the example of the cutting of a steam generator. The collective dose of the personnel during dismantling and removal of the components at the MZFR is compared with the collective dose exposure during the following cutting and treatment at HDB. It is pointed out that the dose limit values are in compliance with the valid radiation protection regulations and the EURATOM basic standards. It shall be demonstrated that cutting and dismantling of highly contaminated and activated parts with high dose rates can be executed safety in terms of both the radiation exposure of the personnel and the technical, financial and time expenditure. (author)