Skip to main content

Historic Preservation - Technical Procedures

Spectitle:

Poulticing Urine Stains From Concrete

Procedure code:

0371038R

Source:

Hstrc Concrete: Investigation & Rpr/Pre-Conf Training - 1989

Division:

Concrete

Section:

Concrete Cleaning

Last Modified:

02/24/2012

Details:

Poulticing Urine Stains From Concrete



POULTICING URINE STAINS FROM CONCRETE


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


PART 1---GENERAL

1.01 SUMMARY

    A.   This procedure includes guidance on removing urine stains
         from concrete using a trichloroethylene poultice or
         hypochlorite solution.

    B.   Safety Precautions:

         1.   DO NOT save unused portions of stain-removal
              materials.

         2.   DO NOT store any chemicals in unmarked containers.

         3.   EXCELLENT VENTILATION MUST BE PROVIDED WHEREVER ANY
              SOLVENT IS USED.  USE RESPIRATORS WITH SOLVENT
              FILTERS.

         4.   No use of organic solvents indoors should be
              allowed without substantial air movement.  Use only
              spark-proof fans near operations involving
              flammable liquids.

         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.

   C.   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).

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


PART 2---PRODUCTS

2.01 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.   For Light Staining:

         1.   Trichloroethylene (highly refined solvent):

              CAUTION:  TRICHLOROETHYLENE IS HIGHLY TOXIC AND MAY
              REACT WITH STRONG ALKALIS SUCH AS FRESH CONCRETE TO
              FORM DANGEROUS GASES.

              a.   Other chemical or common names include Ethinyl
                   trichloride.

              b.   Potential Hazards:  TOXIC.

              c.   Available from automotive supply distributor,
                   chemical supply house (both commercial and
                   scientific), dry cleaning supply distributor,
                   paint store, photographic supply distributor
                   (not camera shop), or printer's supply
                   distributor.

    B.   For Heavy Staining:

         1.   Job-prepared Hypochlorite:  Made by user, see
              03710-01-S for guidance on preparation.

              a.   Calcium Hypochlorite (CaCl2O2):

                   1)   A white powder used especially as a
                        bleaching agent and disinfectant.

                   2)   Other chemical or common names include
                        Chlorinated calcium oxide; Bleaching
                        powder*; Calcium oxymuriate*; Chloride of
                        lime*; Chlorinated lime*; Hypochlorite of
                        lime*; Oxymuriate of lime*.

                   3)   Potential Hazards:  CORROSIVE TO FLESH;
                        FLAMMABLE (WHEN IN CONTACT WITH ORGANIC
                        SOLVENTS).

                   4)   Available from chemical supply house, dry
                        cleaning supply distributor, drugstore or
                        pharmaceutical supply distributor,
                        janitorial supply distributor, swimming
                        pool supply distributor, or water and
                        sanitation supply distributor.

              b.   Sodium Orthophosphate:

                   1)   Other chemical or common names include
                        Tribasic sodium phosphate; Trisodium
                        orthophosphate; Trisodium phosphate;
                        TSP*; Phosphate of soda*.

                   2)   Potential Hazards:  CORROSIVE TO FLESH.

                   3)   Available from chemical supply house,
                        grocery store or supermarket or hardware
                        store.

    C.   Filler material such as diatomaceous earth or powdered
         talc

    D.   Cotton wadding for bandage

    E.   Mineral water

    F.   Clean dry towels for blotting the area after treatment

    G.   Clean, potable water

    H.   Accessible source of water, soap and towels for washing
         and rinsing in case of emergencies associated with the
         use of chemicals

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.   Stiff bristle brush (non-metallic)


PART 3---EXECUTION

3.01 PREPARATION

    A.   Protection:

         1.   Provide adequate wash solutions (i.e. water, soap
              and towels) before starting the job.

         2.   Whenever acid is used, the surface should be
              thoroughly rinsed with water as soon as its action
              has been adequate.  Otherwise it will continue
              etching the concrete even though the stain is gone.

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
    WASHED AWAY.

    A.   For Light Stains:

         1.   Saturate 3- or 4-layers of cotton wadding in
              trichloroethylene.

         2.   Apply the treated bandage to the stained surface
              extending it well beyond the edges of the stain and
              allow to sit for one hour.

         3.   Remove the bandage periodically, wring out,
              resaturate and reapply.  On horizontal surfaces,
              use concrete slabs or flat stones to hold the
              bandage in place.  On vertical surfaces some kind
              of prop should be devised to hold the bandage
              against the concrete.  

         4.   Repeat the process as necessary to achieve the
              desired level of cleanliness.

         5.   Remove the bandage and scrub the surface with a
              stiff bristle brush, scouring powder and clean
              water.

         6.   Thoroughly rinse the area with clean, clear water
              and allow to dry.

         7.   Repeat the process as necessary to achieve the
              desired level of cleanliness.

    B.   For Heavy Stains:

         1.   Mix enough diatomaceous earth or talc with a clear
              hypochlorite solution to make a thick paste.  For
              guidance on making job-prepared hypochlorite see
              03710-01-S.

         2.   Thoroughly wet the concrete surface to be treated
              with clean, clear water.

         3.   Apply the poultice to the stained area to a
              thickness of 1/4 inch using a wood or plastic
              spatula and allow to dry.  Be sure to spread the
              poultice well beyond the stained area.  The liquid
              portion of the paste will migrate into the concrete
              where it will dissolve some of the staining
              material.  Then the liquid will gradually move back
              beyond the concrete surface and into the poultice,
              where it will evaporate, leaving the dissolved
              staining material in the poultice.

         4.   When the poultice has dried, brush or scrape it off
              with a wooden scraper.  

         5.   Using a stiff bristle brush, scrub the surface with
              scouring powder and clean water to remove any
              residual staining.

         6.   Thoroughly rinse the area with clean, clear water
              and allow to dry.

         7.   Repeat the process as necessary to achieve the
              desired level of cleanliness.

                         END OF SECTION