A crane for lifting and transporting loads includes a base frame to transfer loads onto a support surface by a plurality of contacts in contact with the surface. An arm for lifting loads is rotatable relative to the base frame around a vertical axis. The angular range of the arm around the vertical axis includes angular fields, and load sensors. Each load sensor is associated with a respective contact to detect the force on the support surface. A control system obtains, from the load sensors, the value of the force, and detects the angular field where the arm is located. The control system determines a danger condition based on the values detected by the load sensors, according to different criteria in at least two different angular fields. The control system carries out predetermined functions of the crane, if the danger condition is reached.