This paper presents a CPS(Cyber-physical System) home safety architecture for home safety problem detection and reaction and shows some example cases. In order for home safety problem detection, there are three levels of events defined: elementary event, semantic event and entire event, which representing the meaning from parameter to single safety problem, and then the whole safety status of a house. For the relationship between these events and raw data, a Finite State Machine (FSM) based modeling is applied. Including the raw data, these are taken as input and output to the three levels of FSMs. By using this way of event composition, not only single safety problem, but also safety level of the whole house can be precisely described. In order to verify the mechanism of hierarchical FSMs and by using this mechanism, safety problems and safety level of a house can be correctly represented. And also verify that different levels of events can precisely representing what is happening. Two simulation cases are proposed: one is heat stroke and another is carbon monoxide poisoning. The simulation result shows that the simulation targets are satisfied.