Historic Preservation - Technical Procedures
- Evaluating When Lead Paint Mitigation Is Necessary
- Procedure code:
- 1994 Crm, Vol.17, No. 4/1997 Windows Conference Paper
- Last Modified:
- Evaluating When Lead Paint Mitigation Is Necessary
- Last Modified:
EVALUATING WHEN LEAD-BASED PAINT MITIGATION IS NECESSARY
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.
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
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
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
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
Has a paint inspection and/or risk assessment been performed by a
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 level
guidelines 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 800
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
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
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.
END OF SECTION