I have had my home security alarm go off precisely because of mylar balloons in the room.
Originally Posted by
Bobster
I've been doing some reseach, and I read that a mylar ballon will trigger a PIR sensor. Hang the ballon near the sensor and let the air currents move it around, so the sensor will think somebody is always in the room.
I haven't verified this. But apparently mylar reflects infrared.