Then, I took the trash to the basement around 1:30. As I got off the elevator on the third floor a little before 2:00, I thought I heard a high-pitched ringing; ut lasted maybe three seconds, then there was a pause of 3-5 seconds before it rang again. It was not loud, but my fear was someone's smoke detector was going off. I called 911, and ten minutes laterI spoke to three firemen who confirmed there was an alarm ringing somewhere in the building. I guess everything is uder control since we've not been ordered to evacuate.