There are 4 main cleaning codes when it comes to cleaning upholstery fabrics. Each one is different but has some things in common. Certified upholstery cleaning companies with trained and experienced technicians can clean them all. 

Cleaning Code "W" – These are the easiest fabrics to maintain and clean most effectively. Fabrics with this code mean they are designed for very busy areas and can be steam cleaned for optimal results. They are also easy to maintain and remove stains.  With "W" coded fabric is that you don't need any stain repellent applied to it. Water-based products work best on these fabrics anyway.

Cleaning Code "WS" –  This is also a good choice of fabrics for everyday use. They are not as strong as "W" coded fabrics, but they are also easy to maintain with proper professional care from certified upholstery cleaning firms. Fabrics with this code would benefit greatly from applying a solvent-based stain repellent treatment. 

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Cleaning Code "S" –  Fabrics with this code do not like water and can be seriously damaged by wet cleaning methods or staining with water-based products. Clean stains with a mild, waterless solvent or a dry cleaner. Clean only in a well-ventilated room and never use any product that contains carbon tetrachloride, which is very toxic. Fabrics with this code need maintenance cleaning more frequently than the first two coded fabrics.

Cleaning Code "XS or X" – This type of fabric you never want to buy. It cannot be cleaned with either solvent or water, and even a stain repellent treatment will discolor the fabric, causing possible shrinkage and distortion of fabric lint. This fabric can only be vacuumed.