A few "safe as houses" alarms have been redesigned in an attempt to reduce the large number of complaints where alarms have sounded by accident. one of the new types of alarms is less sensitive than its predecessors. studies have shown that these newer alarms are rarely activated for no reason. "safe as houses" still sells a number of the original, sensitive alarm systems, because the increase in threshold for motion detection means that the new style alarms may fail to register break-in where limited force is being used.(some people prefer to buy alarms that sometimesactivate for no reason).