Note from JWR:

I was up on the roof yesterday, doing the semi-annual de-gunking of the wood stove chimney spark arrestor, and the annual cleaning of the chimney itself. A messy job, but one that is crucial for fire safety. (Creosote-fueled chimney fires are commonplace, and are almost always the result of lax chimney-cleaning discipline.) Every survival retreat owner should have a set of chimney-cleaning rods and brushes, and the discipline to use them regularly!