Wool is characterized by a number of special properties and is therefore almost completely self-cleaning. The protein in wool neutralizes odors and pollutants from sweat. Bacteria have less chance of development and cannot develop unpleasant odors. Wool contains wool fat (lanolin). This means that water and dirt cannot penetrate a fiber. Wool is even dirt-repellent! Washing is therefore not always necessary. Shaking something out and ventilating well outdoors can work wonders.