I've had no complaints . Back before cell phones I had a intercom in the shop so I could hear the house phone ring. Just fired some green coal, bay doors open smoke rolling out. Phone rang , I ran to house 100 yards away. Neighbor had a friend visiting . Seeing the smoke and me running . He told my neighbor to call 911 and he would run over and help. . She looked out the door , told him to calm down ,that's normal.