Sensor device and care support system

Provided is a care support system which can ensure an appropriate response by care workers, etc. by promptly notifying events of persons in need of care, etc. while reducing network traffic to thereby reduce the burden on the care workers, etc. and quickly ensure safety of the persons in need of care. A sensor box SB itself determines that a subject has tripped and fallen or fallen from somewhere on the basis of image data corresponding to the subject's state. Thus, compared, for example, to when a management server SV determines the fall, the need to send a large amount of image data is eliminated so that traffic is limited and internet congestion is avoided. Further, a ring buffer 16 overwrites and stores the image data obtained by a camera 112 for a certain period of time, and when an SB control processing unit 14 determines that a specific event (a fall) has occurred to a subject Ob on the basis of the image data, the SB control processing unit 14 cuts out a portion of the image data stored in the ring buffer 16 and saves the same in a temporary retirement buffer 17. Thus, by viewing, after the event, the image data saved in the temporary retirement buffer 17, it can be accurately determined under what circumstance the specific event occurred to enable appropriate measures to be taken and to prevent the same thing from happening again.