Skip to main content

Historic Preservation - Technical Procedures

Spectitle:

Removing Oil And Fat Stains From Marble

Procedure code:

0445511R

Source:

Outdoor Sculpture Manual - Center For Public Buildings

Division:

Masonry

Section:

Marble

Last Modified:

06/28/2012

Details:

Removing Oil And Fat Stains From Marble



REMOVING OIL AND FAT STAINS FROM MARBLE


THE CLEANING OR REMOVAL OF STAINS FROM STONE MAY INVOLVE THE USE
OF LIQUIDS, DETERGENTS OR SOLVENTS WHICH MAY RUN OFF ON ADJACENT
MATERIAL, DISCOLOR THE STONE OR DRIVE THE STAINS DEEPER INTO POROUS
STONES.  USE THE PRODUCTS AND TECHNIQUES DESCRIBED HERE ONLY FOR
THE COMBINATIONS OF DIRT/STAIN AND STONE SPECIFIED.


PART 1---GENERAL

1.01 SUMMARY

    A.   This procedure includes guidance on poulticing marble
         stained with oil and fat containing substances such as
         oil based paints, lipstick, butter, cream, milk, peanut
         butter, hand lotions, mustard and deposits bound to the
         surface by or consisting entirely of oils, grease and/or
         bituminous products.  

    B.   Oil stains are usually light brown or yellow in color.

    C.   Most oil based products are composed of some material,
         often pigmented, suspended in an oily vehicle.  When such
         a product is applied to a surface, the oil tends to
         penetrate into porous substrates such as masonry.  The
         pigmented matrix may rest on the surface, while the oil
         is absorbed into the stone, generally causing a darkening
         effect.

    D.   Poulticing is the most effective means of removing oil
         and fat stains from marble.  A solvent is used to
         dissolve the oil, and a medium is applied to the surface
         which absorbs the oil, drawing it to the surface and into
         the poulticing medium as it dries.

         1.   Stain removal by conventional washing is usually
              impossible.  The pigmented matrix may be removed by
              scraping or washing; however, the dark oil stains
              are usually quite apparent, especially on white or
              light colored stone.  

         2.   Abrasive cleaning techniques are INAPPROPRIATE and
              NOT RECOMMENDED, as they result in excessive loss
              of surface material and altered texture.
              Furthermore, abrasive cleaning will not remove
              deeply penetrated oil staining.  

         3.   Steam cleaning is also INAPPROPRIATE and NOT
              RECOMMENDED for this type of stain removal as the
              steam heat reduces the viscosity of the oil and
              drives it deeper into the stone, spreading the
              stain.

    E.   See 01100-07-S for general project guidelines to be
         reviewed along with this procedure.  These guidelines
         cover the following sections:

         1.   Safety Precautions

         2.   Historic Structures Precautions

         3.   Submittals

         4.   Quality Assurance

         5.   Delivery, Storage and Handling

         6.   Project/Site Conditions

         7.   Sequencing and Scheduling

         8.   General Protection (Surface and Surrounding)

         These guidelines should be reviewed prior to performing
         this procedure and should be followed, when applicable,
         along with recommendations from the Regional Historic
         Preservation Officer (RHPO).

    F.   For additional information on poulticing, see 04455-02-R.

    G.   For general information on the characteristics, uses and
         problems associated with marble, see 04455-01-S.


PART 2---PRODUCTS

2.01 MANUFACTURERS

    A.  ProSoCo, Inc.
         www.prosoco.com
         
2.02 MATERIALS

    NOTE:  Chemical products are sometimes sold under a common
    name.  This usually means that the substance is not as pure as
    the same chemical sold under its chemical name.  The grade of
    purity of common name substances, however, is usually adequate
    for stain removal work, and these products should be purchased
    when available, as they tend to be less expensive.  Common
    names are indicated below by an asterisk (*).

    A.   Acetone (C3H6O):

         1.   A volatile fragrant flammable liquid ketone used
              chiefly as a solvent and in organic synthesis and
              found abnormally in urine.

         2.   Other chemical or common names include Dimethyl
              ketone; Propanone

         3.   Potential Hazards:  VOLATILE AND FLAMMABLE SOLVENT

         4.   Available from chemical supply house or hardware
              store.

         -OR-

         Mineral Spirits:

         1.   A petroleum distillate that is used especially as a
              paint or varnish thinner.

         2.   Other chemical or common names include Benzine*
              (not Benzene); Naphtha*; Petroleum spirits*;
              Solvent naphtha*.

         3.   Potential Hazards:  TOXIC AND FLAMMABLE.

         4.   Safety Precautions:

              a.   AVOID REPEATED OR PROLONGED SKIN CONTACT.

              b.   ALWAYS wear rubber gloves when handling
                   mineral spirits.

              c.   If any chemical is splashed onto the skin,
                   wash immediately with soap and water.

         5.   Available from construction specialties
              distributor, hardware store, paint store, or
              printer's supply distributor.

         -OR-

         Commercial cleaner such as "Stand Off Oil and Grease Stain
         Remover" (ProSoCo, Inc.), or approved equal.

    B.   White absorbent material (molding plaster, untreated
         white flour, white tissue, paper towels, powdered chalk,
         talc, baking powder, baking soda, fullers earth or
         laundry whiting), or a commercial absorbent material such

        "Stand Off Poultice Powder"(Prosoco), or approved equal.

    C.   Mineral water

    D.   Plastic sheeting

    E.   Clean dry towels for blotting the area after treatment

2.02 EQUIPMENT

    A.   Glass or ceramic container for mixing the solution

    B.   Wooden utensil for stirring the ingredients

    C.   Wood or plastic spatula

    D.   Masking tape


PART 3---EXECUTION

3.01 EXAMINATION

    A.   Examine the marble surface CAREFULLY to determine the
         cause of staining before proceeding with any cleaning
         operation.

3.02 ERECTION, INSTALLATION, APPLICATION

    NOTE:  BEGIN CLEANING BY USING THE GENTLEST METHOD POSSIBLE.
    TEST CLEAN A SMALL AREA BEFORE ATTEMPTING TO CLEAN LARGE AREAS
    TO DETERMINE APPROPRIATE DWELL TIMES AND NUMBER OF
    APPLICATIONS NECESSARY TO ADEQUATELY REMOVE THE STAIN.  

    A.   Apply a poultice:

         1.   Rinse the area to be treated with mineral water.

         2.   Mix the acetone or mineral spirits in a glass or
              ceramic bowl.  Use an amount adequate to fully
              cover the affected area.

         3.   Thoroughly moisten the stained surface with this
              liquid.  Be sure to dampen well beyond the stain.

         4.   Mix the remaining liquid with the white absorbent
              material to form a paste the consistency of oatmeal
              or cake icing.  (Approximately one pound of paste
              is needed for every square foot of surface area to
              be treated).

         5.   Using a wooden or plastic spatula, apply the paste
              to the stained surface in layers no more than 1/4
              inch thick.  The poultice should extend well beyond
              the stain to prevent forcing the stain into
              previously clean stone.

         6.   Check the coating for air pockets or voids.

         7.   Cover the poultice with plastic sheeting and seal
              with masking tape.

         8.   Let set for 48 hours (unless otherwise specified).

         9.   After set period, dampen the poultice with mineral
              water.

         10.  Remove the poultice with a wooden or plastic
              spatula to avoid scratching the surface.

         11.  Again, thoroughly rinse the cleaned area with
              mineral water, blot with clean towels and allow the
              surface to dry.

         12.  Once the surface has dried completely, check for
              remaining residue and repeat the treatment if
              necessary.

    -0R-

    B.   Apply a commercial cleaner following manufacturer's
         instructions.

                         END OF SECTION
 


oil on marble,fat on marble,poultice,poulticing oil or fat stains,oil, paint,lipstick,butter, cream,milk,peanut butter,lotion,oil,grease,bituminous