Motion sensors vs Occupancy sensors

I recently bought a ST to start my automation journey. My requirement is that if a person enters a room, the light in the room, should automatically turn on and stay turned on as long as the person is present in the room. My question is do the latest motion sensors have this capability or shall I go for occupancy sensors?
The other solution is that I can configure the motion sensors to keep the light on for an hour once someone enters the room, but if the person leaves the room in few minutes, lights will stay on for the remaining time, wasting the energy and increasing lights bills.
I see there are some threads on this topic, but they are pretty old, so checking if something has evolved.
Thanks!!

I think most motion sensors will not reset until a certain period of “no motion”. But, of course, people don’t keep moving in any particular room (within range of the sensor), so those are not optimal. Multiple sensors in the room help; as could so extra coding to determine occupancy (there is a SmartApp published here somewhere; not sure it is perfect either, but worth a try - I don’t even remember its name…).

The only “occupancy sensor” (that I’m aware of) are Bluetooth based “Beacons” which @JDRoberts has some regarding. They are not directly compatible with SmartThings.

I use motion sensors which work pretty well, you just need to place them in the right place so that they always pick up movement or use multiple sensors as tgauchat sugguested. They are not perfect, but 90% of the time work well enough. Not really sure if there are any zwave/zigbee occupancy sensors, I would imagine a true occupancy sensor would need to detect body heat and not motion.

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I think sensors with complex “infrared video chips” can detect body heat, but I doubt there are many affordable reliable ones at this time.

PIR Motion Sensors (i.e., the kind we all use these days!!!) use IR to detect body heat … but it triggers from that “wave” of body heat moving across a simple sensor causing a ripple of “on/off/on/off” which the device says “aha! motion!”.

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