Soiled rags are often generated by printing and painting operations, and during vehicle and equipment maintenance and repair. Typically, rags are used in cleaning or degreasing operations together with a solvent or mixture of solvents. In practice, a solvent is applied to a rag which is then used to clean a surface or the solvent is applied to a surface which is then cleaned with a rag. Rags can also be used to wipe off excess paint or printing inks from work surfaces. This process is repeated until the rag becomes so contaminated that it must be discarded or cleaned before reuse. Rags may also be used in the application of stains or in cleaning up spills of paint, solvents, or other liquids.
Discarded rags could contain toxic levels of characteristic hazardous waste such as lead or methyl ethyl ketone (MEK). It is even more likely that the discarded rags may be contaminated with an F-listed hazardous waste such as a solvent or degreaser (typically acetone, xylene, toluene, MEK, MIK, tetrachloroethylene, trichloroethylene). Solid wastes mixed with listed hazardous waste generally remain a listed hazardous waste.
Rags that are hazardous waste and must be disposed of as such:
- Soiled rags which are used to remove applied solvents from equipment during cleaning operations if F-listed solvents are used or if the resulting mixture is ignitable.
- Soiled rags to which an F-listed or ignitable solvent has been added for cleaning purposes.
- Soiled rags used to clean up a spill of a hazardous material such as solvents or other ignitable materials.
Rags which are non-hazardous and can be disposed of into the sanitary trash:
- Soiled rags used to clean up spilled paint.
- Soiled rags used in the cleaning operations involving non-hazardous chemicals.
- Soiled rags used in the application of stains.
- Rags contaminated with oils where no solvents are involved.
If free liquids are present in nonhazardous rags, absorbent may be added prior to disposal or they may be allowed to air dry. No free liquids are to be placed into the sanitary trash.
If there is any question as to whether or not a rag should be considered a hazardous waste, contact the Director of Environmental Management (417-836-8334).
Waste Management Options
Solvent contaminated rags generated on the University campuses must be stored in accordance with the hazardous waste accumulation regulations. Rags that are potentially hazardous waste will be placed in the appropriately marked containers. The containers must be kept securely closed to prevent the release of fumes or spillage of the “waste”. The rags will be shipped off-site as a waste flammable solid.
Where possible, Missouri State will convert to equally effective nonhazardous cleaning solvents.