FIBER GUARD FIBER GUARD STAIN PROTECTION & CLEANING FOR CARPETS & UPHOLSTERY. What is FIBER GUARD FIBER GUARD is a specially formulated treatment for carpets, fabrics and upholstery which provides protection against the damage caused by soil & stains. FIBER GUARD does not change the colour of texture of your fabric of carpets. The advantages of using FIBER GUARD are: Spills and stains can ...