How are you allowed to transport persons on trailers used for agricultural purposes?

You answered correctly. When transporting people on agricultural trailers, German traffic rules allow it if they are sitting on proper seats, ensuring safety. In some situations, such as when someone must accompany a load, standing is also allowed, but only if it is necessary for supervising or handling the cargo. However, standing on empty trailers is never permitted, as it poses unnecessary risk. Always make sure either proper seats are used or, if standing, it is only for essential supervision of the load on agricultural trailers. This ensures both compliance with the law and safety for everyone involved.