Evaluating When Lead Paint Mitigation Is Necessary

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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.

The 1995 Housing and Urban Development (HUD) guidelines regarding the evaluation and control of lead-based paint hazards were 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.

This procedure includes guidance on how to evaluate when and if lead-based paint mitigation is necessary. Based on the 1995 HUD Guidelines, mitigation strategies can best be developed by asking a few questions and evaluating the answers together with a complete paint inspection and risk assessment. The following adaptation summarizes the HUD pathology and should aid in determining what lead-reduction actions should be taken.

Was the building built before 1978

The use of lead in paint was prohibited in the United States after 1978. If the building was constructed prior to 1978, it is likely that some, if not much of the paint used contained lead. HUD has estimated in a 1990 report to Congress that 90% of all privately owned dwellings built before 1940 had painted surfaces that contained lead-based paint. A figure of 80% is used to summarize the lead-based paint presence in dwellings built between 1940 and 1959. In dwellings built between 1960 and 1979, the presence of lead-based paint is further reduced to 62%. These statistics for housing may also be representative of other building types constructed during these time periods.

Are there any known cases of elevated blood-lead levels in building occupants?

Ingestion of lead-contaminated dust is the most common means of developing lead-poisoning, especially in older buildings where dust levels are naturally higher. Sources may include loose/peeling/chipping lead-based paint or lead accumulations in the soil. Adults may become symptomatic with elevated blood-lead levels of 40-50 micrograms/deciliter. Children under the age of six are at higher risk than adults for exposure to low levels of lead. Therefore, the maximum exposure level for children, before intervention, is 10 micrograms/deciliter.

Is the building historic and are preservation regulations applicable based on the age and/or significance of the structure?

Technically, any building fifty years of age or older is considered historic and is potentially eligible for listing on the National Register of Historic Places until it is deemed ineligible based on review of its qualifications. GSA manages a tremendous number of historic buildings throughout the country and has an obligation to administer these cultural properties under its control in a spirit of stewardship and trusteeship for future generations. In light of the historic preservation concerns associated with any building (in this case, GSA buildings), a formal paint inspection and risk assessment should be performed by a trained and certified lead hazard inspector as described below.

Has a paint inspection and/or risk assessment been performed by a licensed professional?

A paint inspection investigates the presence of lead-based paint on a surface-by-surface basis.

Is there lead-based paint present, and where is it?

A risk assessment evaluates the presence of lead-based paint hazards. This includes identifying sources or potential sources of lead contamination (such as friction or impact surfaces), locating lead-based paint through testing and evaluation of its condition, documenting the building and occupant type, and assessing the risks of lead exposure based on the building function and occupant make-up. The best type of lead-based paint evaluation would combine a paint inspection along with a risk assessment in order to develop an appropriate mitigation plan.

Evaluation techniques might include X-Ray Fluorescence testing (XRF) or dust-wipe sampling. XRF is useful in determining potential hazardous conditions by inspecting the lead content of sound paint. Dust-wipe sampling is a method of evaluating existing hazards by sampling dust accumulations (typically on the floor, window sills and window trough) for lead content. The results are then compared with the dust lead levelguidelines established by HUD to determine if the amount of lead measured is considered hazardous. For floors, lead levels above 100 micrograms/sq. ft. is considered hazardous; for window sills, the hazardous level is anything above 500 micrograms/sq. ft.; for window troughs, the hazardous level is anything above 800micrograms/sq. ft.`

What method of lead-hazard reduction is preferable and/or acceptable by the Regional Historic Preservation Officer? Is abatement required or necessary, or is implementing interim controls an acceptable strategy?

Abatement is classified by HUD as any treatment for eliminating lead-based paint that is considered permanent, or rather, capable of lasting twenty years. This may include any of the following: Complete removal of the lead-based paint; removal and replacement of the lead-based paint component; enclosure of the component or surface; or application of an encapsulant coating. For guidance on reducing lead-based paint hazards using abatement techniques on windows, see 09900-02-R. 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. These less aggressive methods of lead hazard control are typically preferred 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.

For guidance on reducing lead-based paint hazards using interim control techniques on windows, see 09900-03-R.The best approach to lead-based paint reduction usually involves a combination of both abatement and interim control techniques. For specific guidance in combining both of these techniques to achieve lead hazard reduction, see 09900-04-R. For information on general protection measures to reference during lead-based paint hazard-reduction work, see 09900-10-S. It should be noted that the highest risks of exposure to the hazards of lead-based paint are generally associated with housing, day care facilities or other building types where ingestion is more likely to occur. In these building types, abatement techniques may be a higher priority and may also be the only acceptable alternative. Occupants of office environments, on the other hand, are generally at a much lower risk of exposure to these hazards. In these cases, interim control methods would often be an acceptable mitigation solution. A complete risk assessment, however, is always recommended and would reveal the most important factors to consider before making any mitigation plans.