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Historic Preservation - Technical Procedures

Spectitle:

Removing Copper, Silver And Nickel Stains From Ceramic Tile

Procedure code:

0931005R

Source:

Hspg Prepared For Nps - Sero

Division:

Finishes

Section:

Ceramic Tile

Last Modified:

02/24/2012

Details:

Removing Copper, Silver And Nickel Stains From Ceramic Tile



REMOVING COPPER, SILVER AND NICKEL STAINS FROM CERAMIC TILE


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


PART 1---GENERAL

1.01 SUMMARY

    A.   This procedure includes guidance on removing copper,
         silver and nickel stains from ceramic tile.

    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).


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.   Household ammonia:

         CAUTION:  DO NOT MIX AMMONIA WITH CHLORINE BLEACHES, A
         POISONOUS GAS WILL RESULT!  DO NOT USE BLEACH ON BIRD
         DROPPINGS.

         1.   Other chemical or common names include Ammonium
              Hydroxide; Ammonia water*; Aqua ammonia*.

         2.   Potential hazards:  TOXIC; MAY IRRITATE THE EYES.

         3.   Available from chemical supply house, grocery store
              or pharmaceutical supply distributor, or hardware
              store.

    B.   Nitric acid (HNO3):

         1.   A corrosive liquid inorganic acid used especially
              as an oxidizing agent, in nitrations, and in making
              organic compounds such as fertilizers, explosives
              and dyes.

         2.   Potential Hazards:  CORROSIVE TO FLESH; CORROSIVE
              TO CONCRETE, STEEL, WOOD OR GLASS.

         3.   Available from chemical supply house or hardware
              store.

    C.   Clean, potable water

2.03 EQUIPMENT

    A.   Clean natural fiber rags, or sponges

    B.   Stiff bristle brushes (no iron wire)


PART 3---EXECUTION

3.01 EXAMINATION

    A.   Examine the ceramic tile surface carefully to determine
         the type and cause of staining before proceeding with any
         cleaning operation.

3.02 ERECTION, INSTALLATION, APPLICATION

    A.   For Copper Metal Stains:

         NOTE:  DO NOT USE THIS TREATMENT ON GLAZED TILE.

         1.   Wash the surface using a clean cloth or sponge
              soaked with a 10% nitric acid solution.

         2.   Rinse the treated area immediately with clean,
              clear water and allow to dry.

    B.   For Silver and Nickel Stains:

         1.   Wash the affected area using a clean cloth or
              sponge soaked with household ammonia.

         2.   Rinse the treated surface with clean, clear water
              and allow to dry.

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

                             END OF SECTION