 Inherently flame-retardant fabrics such as certain brand polyesters are commonly used for flame retardant curtain fabrics.Fire-retardant fabrics are normally treated to different British Standards; normally this depends on the end usage of the fabrics.BS 476 is a fire treatment for fabrics that are normally for wall hanging, and must only be used as for that purpose, where as CRIB 5 is a fabric fire treatment for upholstery and must only be used for furnishing and upholstery purposes, even if both fabrics have been treated for fire-retardancy.