Removing Ink Stains From Terrazzo Floors

Technical Procedures Disclaimer

Prior to inclusion in GSA’s library of procedures, documents are reviewed by one or more qualified preservation specialists for general consistency with the Secretary of Interior Standards for rehabilitating historic buildings as understood at the time the procedure is added to the library. All specifications require project-specific editing and professional judgement regarding the applicability of a procedure to a particular building, project or location. References to products and suppliers are to serve as a general guideline and do not constitute a federal endorsement or determination that a product or method is the best or most current alternative, remains available, or is compliant with current environmental regulations and safety standards. The library of procedures is intended to serve as a resource, not a substitute, for specification development by a qualified preservation professional.

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We’ve reviewed these procedures for general consistency with federal standards for rehabilitating historic buildings and provide them only as a reference. Specifications should only be applied under the guidance of a qualified preservation professional who can assess the applicability of a procedure to a particular building, project or location. References to products and suppliers serve as general guidelines and do not constitute a federal endorsement nor a determination that a product or method is the best alternative or compliant with current environmental regulations and safety standards.

PART 1---GENERAL

1.01 SUMMARY

A. This procedure includes guidance on removing ink stains from terrazzo floors.

B. 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).

C. For general information on the characteristics and maintenance of terrazzo, see 09400-01-P.

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 (*).

  1. For Ordinary Ink Stains:
    1. Sodium Perborate:
      1. Other chemical or common names include Perborax*.
      2. Potential Hazards: TOXIC AND FLAMMABLE (WHEN IN CONTACT WITH ORGANIC SOLVENTS).
      3. Available from chemical supply house, drugstore or pharmaceutical supply distributor, grocery store or supermarket.
    2. Hot water
    3. Whiting:
      1. Other chemical or common names include Powdered chalk. Kitchen flour may also be substituted.
      2. Available from paint store.
  2. For Bright-Colored Ink Stains:
    1. Ammonia water:
      CAUTION: DO NOT MIX AMMONIA WITH CHLORINE BLEACHES, A POISONOUS GAS WILL RESULT! DO NOT USE BLEACH ON BIRD DROPPINGS.
      1. A weakly basic compound that is formed when ammonia dissolves in water and that exists only in solution.
      2. Other chemical or common names include Ammonium Hydroxide; Aqua ammonia*; Household ammonia*.
      3. Potential hazards: TOXIC; MAY IRRITATE THE EYES.
      4. Available from chemical supply house, grocery store or pharmaceutical supply distributor, or hardware store.
    2. Cotton batting
    3. Javelle water (Made by user). See 03710-02-S for materials, equipment and procedures for preparing Javelle Water.
  3. For Blue Ink and Indelible Ink Stains:
    1. Ammonia water (see Section 2.01 B.1. above)
    2. Cotton batting or cotton gauze

2.02 EQUIPMENT

  1. Wooden Paddle or Trowel
  2. Stoneware Jar
  3. Shallow Enameled Pan
  4. Electric or battery powered scrubbing machines

PART 3---EXECUTION

3.01 EXAMINATION

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

3.02 ERECTION, INSTALLATION, APPLICATION

NOTE: THE FOLLOWING TREATMENTS SHOULD BE USED BY TRAINED AND EXPERIENCED PERSONNEL. IMPROPER USE MAY RESULT IN BLEACHING THE TERRAZZO MATRIX, IF A COLOR DYE WAS ADDED AT THE TIME OF INSTALLATION.

  1. For Ordinary Writing Inks:
    1. Make a strong solution of sodium perborate in hot water and mix with whiting to form a thick paste.
    2. Thoroughly wet the surface to be treated with clean, clear water.
    3. Apply the mixture to the stained area in a 1/4 inch thick layer 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 masonry where it will dissolve some of the staining material. Then the liquid will gradually move back beyond the masonry 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 blot dry with clean towels.
  2. For Bright-colored Inks:

    1. Use a sodium perborate poultice as described in Section 3.02 A. above.

    -OR-

    Saturate cotton batting in ammonia water.

    -OR-

    Saturate cotton batting in javelle water (see

    03710-02-S for procedures on preparing Javelle

    Water) and mix with whiting to form a thick paste.

    -OR-

    Mix equal parts of chlorinated lime and whiting reduced to a paste with water.

    2. Follow poultice preparation and application procedures described above in Section 3.02 A.2-7. Repeat the treatment as necessary to achieve the desired level of cleanliness.

  3. For Blue Inks: Some blue ink stains cannot be removed by the perborate poultice, Javelle water, or chlorinated lime poultice.
    1. Saturate cotton batting in ammonia water.
      -OR-
      Use a strong soap solution in place of ammonia water.
       
    2. Follow poultice preparation and application procedures described above in Section 3.02 A.2-7. Repeat the treatment as necessary to achieve the desired level of cleanliness.
  4. For Indelible Inks:
    1. Treat the same as blue ink stains.
    2. For more difficult stains such as inks containing silver salts (causing a black stain), saturate ammonia water in cotton gauze.
    3. Follow poultice preparation and application procedures described above in Section 3.02 A.2-7. Repeat the treatment as necessary to achieve the desired level of cleanliness.