An automatic door operator for use in an entrance system that comprises a swing door member being operable between a closed position which prevents passage, and an open position which admits passage, the automatic door operator comprising: an electric motor; an activation sensor configured for manual actuation by a person wishing to pass through the entrance system; and a controller having a normal operating mode and an emergency mode, wherein, in the normal operating mode, the controller is responsive to the activation sensor and configured for: when the activation sensor is actuated, controlling the motor to generate torque for causing the door member in the entrance system to move from the closed position to the open position, and to stay in the open position during a configured hold open period, and when the configured hold open period has lapsed and the activation sensor is maintained actuated, controlling the motor to generate torque for causing the door member to remain in the open position during an extended hold open period; wherein, in the emergency mode, the controller is responsive to the activation sensor and configured for controlling the motor, when the activation sensor is actuated, to generate torque for causing the door member in the entrance system to move from the closed position to the open position, to stay in the open position during the configured hold open period, but ignore a spurious indication of a maintained actuation of the activation sensor and thereby prevent the door member from remaining in the open position during an extended hold open period. an electric motor; an activation sensor configured for manual actuation by a person wishing to pass through the entrance system; and a controller having a normal operating mode and an emergency mode, wherein, in the normal operating mode, the controller is responsive to the activation sensor and configured for: when the activation sensor is actuated, controlling the motor to generate torque for causing the door member in the entrance system to move from the closed position to the open position, and to stay in the open position during a configured hold open period, and when the configured hold open period has lapsed and the activation sensor is maintained actuated, controlling the motor to generate torque for causing the door member to remain in the open position during an extended hold open period; when the activation sensor is actuated, controlling the motor to generate torque for causing the door member in the entrance system to move from the closed position to the open position, and to stay in the open position during a configured hold open period, and when the configured hold open period has lapsed and the activation sensor is maintained actuated, controlling the motor to generate torque for causing the door member to remain in the open position during an extended hold open period; wherein, in the emergency mode, the controller is responsive to the activation sensor and configured for controlling the motor, when the activation sensor is actuated, to generate torque for causing the door member in the entrance system to move from the closed position to the open position, to stay in the open position during the configured hold open period, but ignore a spurious indication of a maintained actuation of the activation sensor and thereby prevent the door member from remaining in the open position during an extended hold open period.