The subject of natural fibers encompasses several different aspects and each is handled differently. Natural Fibers would include fibers such as Wool, Cotton, Silk, and Sisal.  Certain precautions are common to all of these such as pH sensitivity, color bleed, and browning issues. Using products specifically designed to work with these fibers such as Step 1 (Color Stabilizer) and Step 2 (Soil Break) as well as Step 3 (Extraction Rinse and Finish) and OMS will go a long way towards preventing costly mistakes when dealing with these rugs. 

Many of the same principles used in cleaning upholstery are also used for cleaning area rugs carpeting.