Is insulation with EPS fire barrier necessary for a multi-family house?

Hello, I want to insulate my multi-family house (building class III, as it is under 7 m high up to the top building ceiling) with EPS. Even the consultant, who wants to sell everything, cannot tell me exactly whether a fire barrier is necessary or not. If I look at the Bavarian building regulations or Google now, it is not possible for me to get the information. Everyone writes something different.

Does anyone here perhaps know?