A safety control system has a control unit with safety control logic, a safety sensor arrangement, a machine arrangement operable in different operation modes, each operation mode having a different productivity, the control unit receiving and evaluating input from the safety sensor arrangement, and, in reaction to evaluation result(s), activating an operation mode determined by the safety control logic, the safety sensor arrangement having at least two functionally redundant subsystems, control unit input including information indicating availability of the functionally redundant subsystems, the control logic being configured to activate normal operation mode with normal productivity if input indicates availability of all subsystems, activate fail-stop operation mode with zero productivity if input indicates unavailability of all subsystems, activate fail-operate operation mode with productivity less than normal but above zero if input indicates at least temporary unavailability of at least one and availability of at least another one of the subsystems.