Are you obliged to keep at least 1 metre distance from the stationary object you are passing?

No, the regulations do not specify a minimum distance of 1 metre when passing an obstacle. Art. 23 para. 1 pt. 2 of the Road Traffic Act requires maintaining a "safe distance", which the driver assesses independently. The obligation to maintain a distance of not less than 1 metre applies to the manoeuvre of overtaking (not passing) a bicycle, cycle rickshaw, moped, motorcycle, or a column of pedestrians.