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.
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.
REDUCING LEAD-BASED PAINT HAZARDS USING INTERIM CONTROL TECHNIQUES ON WINDOWS
The 1995 Housing And Urban Development (HUD) guidelines regarding the evaluation and control of lead-based paint hazards were developed in order to provide guidance in lead abatement/reduction work required for federally assisted housing projects. Though these guidelines are not enforced on private housing projects or projects involving other building types, they are a well-recognized reference for making buildings lead-safe, and their use as a resource is recommended in any construction project requiring lead- reduction work. For this reason, these guidelines are frequently referenced in this and other related procedures.
A. This procedure includes guidance on removing lead-based paint from windows using interim control techniques.
B. Interim controls are temporary methods of controlling lead-based paint hazards and include special cleaning and dust removal procedures, stabilization of the existing paint film, and special treatment of friction and impact surfaces. Abatement, on the other hand, is considered to be a permanent treatment for eliminating lead-based paint and may include complete removal of the paint or the feature/component itself.
C. Interim control techniques are preferred over abatement in preservation work since more original material can be retained and preserved. However, regular maintenance is required and necessary in order for this type of strategy to be successful. This works well in office environments with dedicated cleaning and maintenance staff.
D. For guidance in evaluating mitigation strategies for lead-hazard reduction, see 09900-03-S. For general protection measures in lead-based paint hazard reduction work, see 09900-10-S. For guidance in reducing lead-based paint hazards using abatement techniques or combination of abatement and interim control techniques on windows, see 09900-02-R and 09900-04-R respectively.
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
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).
A. Red Devil, Inc.
Pryor, OK 74361
B. ProSoCo, Inc.
Lawrence, KS 66117
C. Diedrich Technologies, Inc.
Schenectady, NY 12303
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 general cleaning or 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. Trisodium Phosphate (TSP):
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 ENVIRONMENTAL QUALITY.
1. Strong base-type powdered cleaning material sold under brand names.
2. Other chemical or common names include Sodium Orthophosphate; Tribasic sodium phosphate; Trisodium orthophosphate; TSP*; Phosphate of soda*; (also sold under brand names such as Red Devil).
3. Potential Hazards: CORROSIVE TO FLESH.
4. Available from chemical supply house, grocery store or supermarket or hardware store.
5. Commercial TSP supplied by Red Devil, Inc.
B. Chemical paint stripper (ProSoCo, Inc., Diedrich Technologies, or approved equal).
C. Clean, potable water
D. Masking tape
E. Primer and paint (use same manufacturer)
F. Encapsulant paint (only for sills)
G. Deglossing agent
H. Screws or wood stops
I. Razor blade
A. Putty knife
B. Sponge sanding block
3.01 ERECTION, INSTALLATION, APPLICATION
A. Cleaning and Dust Control: Clean window sills and troughs frequently (at least twice-a-week) by wiping the surface with a sponge or cloth soaked in a mixture of TSP and water.
NOTE: CLEANING WILL ONLY BE EFFECTIVE IF PERFORMED ON A
REGULAR, SCHEDULED BASIS.
B. Paint Stabilization: Similar to typical paint maintenance except for the use of water to control the spread of led dust.
6. Mist the surface with water and scrape off loose paint using a putty knife.
7. Feather edges using a sponge sanding block saturated with a deglossing agent.
8. Apply a good quality primer and top coat of paint. Use the same manufacturer.
NOTE: The application of an encapsulate paint is not considered an interim controls, but rather an abatement technique. Encapsulant paints are applied so as to completely cover the potentially hazardous area - trapping any failing paint layers under its durable, elastic skin. These paints are also quite expensive and can obscure fine detailing because of its thick consistency.
C. Treatment of Friction and Impact Surfaces: Friction and impact surfaces on windows include components that can become abraded each time the window is opened or closed, such as the sash, the jamb, the parting bead and the interior stop.
1. Mist the interior stop for the lower sash with water.
2. Score the edges with a razor blade and remove the stop. Note: If desired, apply a strip of masking tape over the edge before scoring. This will aid in catching any paint that is chipped in the process.
3. Replace the stop, or if it is desirable to keep the existing stop, treat the friction surface as described below for the treatment of the sash.
4. Remove the sash. If desired, both the upper and lower sash may be treated alike. If the upper sash is painted shut, treatment of the lower sash only is acceptable.
5. Remove the paint from the friction edges - where the sash meets or rubs against other window components. Remove the paint at least an inch on all faces of the sash. The edge facing the jamb should not need treatment, as it is typically not painted.
a. Wet plane or wet scrape to remove the paint; mist the surface with water and remove loose paint using a putty knife or other tool forscraping.
b. Feather the edges using a sponge block saturated with a de-glossing agent.
6. Remove paint from the friction surfaces of the jamb and parting stop by wet planting and wet sanding as described above.
7. Apply a good quality primer and top coat to the window components and reassemble the window.
D. Treatment of "Chewable and Accessible" Surfaces: These are most notably window sills or other similarly projecting feature at an accessible height.
1. Abatement level treatment is recommended for these types of surfaces and includes completely removing the lead-based paint using a chemical stripper, wet scraping or wet sanding.
2. Or, apply an encapsulant paint to the surface following manufacturer's instructions. This method would be preferred if the sill has some significant detailing or if, for some reason, it is important to retain the existing paint/material.
NOTE: Sills are generally the only window features
an encapsulant paint is recommended for use on. These types of paints are not effective on friction surfaces and are, therefore, not typically recommended for window work.
F. Fixing Windows in Place: If desired, this type of temporary control can eliminate contamination from friction surfaces. This method is not desirable for buildings in which the opportunity for fresh outside air is important.
1. Anchor the sash to the channel of the jamb using the inconspicuous placement of metal hardware or wood stops.
2. After the window has been fixed in place, treat the individual features using paint stabilization techniques or encapsulant paints described above.