From what I understand, an egg will explode due to a bacteria that infects the egg and turns it rotten. The best way to prevent this from happening is to thoroughly clean the incubator between hatches with bleach water. I use a bleach water solution to clean mine out and then let it dry in the sun as its' UV rays kills anything the bleach doesn't get. Knock-on-wood, but I haven't had one explode yet.What makes an egg blow up in an incubator? Just being not fertilized and heating up?