We have a large wool rug in our den. Though we now have the rug professionally cleaned, I initially cleaned the rug by following the instructions I was given. I washed it with mild shampoo and let it dry naturally. Most of the time, this worked well. But one time I cleaned the rug and brought it back inside before it was completely dry. Damp wool is not a pleasant odor. I felt like I was living with a herd of wet, smelly sheep!