I purchased this heater because reviews of lower wattage ones stated that they could not keep chicks warm enough unless they were in the basement or house. Mine were going to be in an attached garage.I was skeptical that this would keep the chicks warm enough because the temperature in the garage was upper 40s. The directions said to keep the heater no closer than 6 inches from the shavings. This was not good enough and the newly hatched chicks were standing to keep warm. I lowered it to 5 inches and they settled down and it worked great afterwards. I did raise the heater to 6 inches after a week. I was not concerned with a risk of fire because the shavings were not hot. That was because the garage was cool. Had the garage been warmer, then 6 inches would have been fine.These heaters work really well. I have an LED light bulb on a timer so the chicks will get a sleep cycle at night. The chicks are much calmer with this method of brooding and are doing amazingly well.The units does have an intense smell of epoxy for the first day. It does go away and then the only smell you will have is chick poo, which is worse. (and normal)You do need to remember to clean out under the heater. The chicks will poop under it a lot and raise the bed up. You should do this every three or four days. I use a dust pan.I have 65 chicks under this one (11x40) and I think that is about the limit. I cannot remember how many chicks the manual states it will cover. While other reviewers stated that you can do more chicks because the chicks are moving around, if you do a nighttime sleep cycle, they all congregate under the brooder heater when it is dark.I will never go back to heat lamps. These work much better, are safer, and cost less to run. It also makes their feathers come in faster because they grow faster when the chicks are exposed to colder temps when they are not under the heater. This does not affect slow feathering breeds, however.