Spot Cleaning Oil Stains On Granite
SPOT CLEANING OIL STAINS ON GRANITE
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 THE
POROUS STONE. USE THE PRODUCTS AND TECHNIQUES DESCRIBED HERE ONLY
FOR THE COMBINATIONS OF DIRT/STAIN AND STONE SPECIFIED.
A. This procedure includes guidance on removing stubborn oil
stains and discoloration in local areas from granite
B. For guidance on spot cleaning other stains on granite,
refer to the following:
1. For iron stains: See 04465-01-R.
2. For copper/bronze stains: See 04465-02-R.
C. Safety Precautions:
1. DO NOT save unused portions of stain-removal
2. DO NOT store any chemicals in unmarked containers.
3. EXCELLENT VENTILATION MUST BE PROVIDED WHEREVER ANY
SOLVENT IS USED. USE RESPIRATORS WITH SOLVENT
NOTE: SOME OF THE SOLVENTS LISTED ARE KNOWN
CARCINOGENS AND MAY BE BANNED IN SOME STATES.
4. No use of organic solvents indoors should be
allowed without substantial air movement. Use only
spark-proof fans near operations involving
5. Provide adequate clothing and protective gear where
the chemicals are indicated to be dangerous.
6. Have available antidote and accident treatment
chemicals where noted.
D. 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
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).
E. For general information on the characteristics, uses and
problems associated with granite, see 04465-01-S.
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. For Scrubbing by Hand:
1. Chemical Cleaning Compound: Hydrofluoric (HF) and
phosphoric (H3PO4) acids in concentrations not
exceeding 5% weight to volume, with surfactants
such as ethoxylated alkylphenols and ethoxylated
alcohols at concentration of 1 to 2% weight to
2. Cleaning Detergent: Cleaning detergent designed
for use on masonry surfaces, free of deleterious
amounts of acids, alkalies and organic materials,
as recommended by manufacturer for masonry surfaces
of work to be cleaned as acceptable.
B. Materials for Use on New Oil Stains (Paste Application):
1. Benzol (C6H6):
a. A colorless, volatile, flammable, toxic,
liquid, aromatic hydrocarbon used in organic
synthesis, as a solvent and as a motor fuel.
b. Other chemical or common names include
Benzene; Benzole; Phene; Phenyl hydride; Coal
naphtha*; Motor benzol*.
c. Potential Hazards: FLAMMABLE.
d. Available from automotive supply distributor,
chemical supply house, dry cleaning supply
distributor, hardware store or paint store.
e. Benzene and benzine should not be confused.
Benzene is a distinct chemical compound
obtained from coal tar. Benzine is a mixture
of aromatic hydrocarbons of similar boiling
points derived from petroleum.
2. Hydrated lime or marble dust
C. Materials for Use on Linseed Oil Stains (Paste
1. Trisodium Phosphate:
NOTE: THIS CHEMICAL IS BANNED IN SOME STATES SUCH
AS CALIFORNIA. REGULATORY INFORMATION AS WELL AS
ALTERNATIVE OR EQUIVALENT CHEMICALS MAY BE
REQUESTED FROM THE ENVIRONMENTAL PROTECTION AGENCY
(EPA) REGIONAL OFFICE AND/OR THE STATE OFFICE OF
a. Strong base-type powdered cleaning material
sold under brand names.
b. Other chemical or common names include Sodium
Orthophosphate; Tribasic sodium phosphate;
Trisodium orthophosphate; TSP*; Phosphate of
soda*; (also sold under brand names such as).
c. Potential Hazards: CORROSIVE TO FLESH.
d. Available from chemical supply house, grocery
store or supermarket or hardware store.
2. Sodium Perborate:
a. Other chemical or common names include
b. Potential Hazards: TOXIC AND FLAMMABLE (WHEN
IN CONTACT WITH ORGANIC SOLVENTS).
c. Available from chemical supply house,
drugstore or pharmaceutical supply
distributor, grocery store or supermarket.
3. Powdered talc
4. Proprietary preparations of paste are also
available and should be used according to their
manufacturer's published instructions.
D. Clean potable water
A. For Poulticing:
1. Glass or ceramic container for mixing the solution
2. Wooden utensil for stirring the ingredients
B. Wood or plastic spatula
C. Stiff bristle brush (non-metallic)
1. The use of wire brushes, steel wool, or abrasive
tools for cleaning will not be permitted.
2. Provide adequate wash solutions (i.e. water, soap
and towels) before starting the job.
3.02 ERECTION, INSTALLATION, APPLICATION
NOTE: DO NOT TRY MORE THAN ONE TREATMENT ON A GIVEN AREA
UNLESS THE CHEMICALS USED FROM PRIOR TREATMENT HAVE BEEN
A. Using a Proprietary Cleaning Compound or Detergent:
1. Apply chemical cleaner or detergent to stained
surface following manufacturer's instructions.
2. Scrub the surface by hand using a stiff (non-
metallic) bristle brush. Begin at the top of the
stained area and work down.
3. Thoroughly rinse the surface with clean, clear
water and allow to dry.
4. Repeat as necessary to achieve the desired level of
B. Poulticing New Oil Stains:
1. Thoroughly rinse the area to be treated with clean,
2. Mix a solution of benzol in a glass or ceramic
3. Thoroughly moisten the stained area with this
solution, being sure to dampen an area well beyond
4. Mix the remaining liquid with hydrated lime or
marble dust to form a paste the consistency of
oatmeal or cake icing.
5. Using a wooden or plastic spatula, apply the paste
over the entire stained area in layers no more than
1/4 inch thick. Extend the poultice well beyond
the stain to prevent forcing the stain into
previously clean stone.
6. Allow to dry (approximately 48 hours).
7. After the poultice has set, dampen it with mineral
8. Remove dried paste with wooden scrapers or
9. Thoroughly rinse the area with clean, clear water
and allow to dry.
10. Check for remaining residue and repeat the process
if necessary to achieve the desired level of
C. Poulticing Linseed Oil Stains:
1. Thoroughly rinse the area to be treated with clean,
2. Make a paste composed of one part trisodium
phosphate, one part sodium perborate and 3 parts
powdered talc, mixed with a strong soap solution.
3. Follow steps 3 to 10 in 3.02 B. above.
NOTE: Finished work shall show no signs of stains, scratches,
streaks or runs of discoloration, mortar damage or other like
defects from use of cleaners. Leave all masonry surfaces neat
END OF SECTION