Shabbat: Walking into Room with Motion Detector

Do not walk into a room on Shabbat that has a motion detector that causes LED lights or room lights to go on--unless you can enter the room without turning them on.
Note If you enter a room and then find that there is a motion detector that will turn on a light or an LED, you should not move until someone else has entered the room and the light has turned on. You may then leave while the light is still on.
Note Sometimes motion detector lights do not always go on, due to a defective detector or because you can walk slowly enough or out of the detector range.  If so, then it is not a “psik reisha” and you may walk past the detector, even if it sometimes does turn on the lights. However, you may not use the light that goes on unless there is enough ambient light from other sources that you can see without needing the triggered light.
Examples
  • If you can avoid triggering the LED by walking slowly, you may enter the room.
  • If you can open a door slowly without triggering the LED, and by letting the door swing closed the LED will light up, you may do so and then walk past the detector while the LED is on, but only if the door takes at least 2.5 seconds to close.

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