operators also check clothing for foreign objects before placing them into the machine. items such as plastic pens will dissolve in the solvent bath and may damage textiles beyond recovery. some textile dyes are "loose" (red being the main problem), and will release dye during solvent immersion. operators will dry clean red clothing separately from lighter-color textiles to avoid color transfer. the solvent used must be distilled to remove impurities that may transfer to clothing. operators checked clothing for dry-cleaning compatibility, including fasteners. many fasteners that decorate clothing either are not dry cleaning solvent proof or will not withstand the mechanical action of cleaning. operators will remove them and restitched them after the cleaning. or, operators will wrap them in a small padded protector. fragile items, such as feather bedspreads or tasseled rugs or hangings, may be enclosed in a loose mesh bag. the density of perchloroethylene is around 1.7 g/cm³ at room temperature (70% heavier than water), and the sheer weight of absorbed solvent may cause the textile to fail under normal force during the extraction cycle unless the mesh bag provides mechanical support.