I currently have 2 heat lamps in the barn (-3 right now) and one in an empty bedroom upstairs where my chick and eggs are. I dust the cover off frequenty, but it never occured to me to dust the bulb! Last night the smoke alarm kept going off in the chick room. My bedroom is downstairs, but I heard it clearly. I ran up there 3 or four times, checking every outlet and dusting the heat lamp and sniffing for smoke. Finally while laying in bed, I thought about the bulb itself! I went back upstairs and unplugged the light. Sure enough there was a thick layer of black, burnt chicken dust on the top side of the bulb!. I cleaned it off well and took the alarm down and blew dust out of it as well. The alarm has not sounded since. I can not believe how much dust the tiny creatures make! I thought I was very safe with these fixtures. I clamp them and then secure them with rope as well, but never thought about dusting the tops of the bulbs! Please check yours. And your smoke alarms too!