Path to the chimney via roof step

Hello, a chimney was installed in the new building that protrudes relatively centrally from the roof. Maintenance openings are planned in the basement. Does a fixed path, e.g. from the roof window or the eaves, have to be created via, for example, roof access steps? Who checks or approves this?

For all questions, the chimney sweep is responsible. He must gain access to the chimney - either over the roof with steps or also with a cleaning hatch in the [DG] (the simpler and cheaper way).