Code of Maine Rules › 06 - DEPARTMENT OF ENVIRONMENTAL PROTECTION › 096 - DEPARTMENT OF ENVIRONMENTAL PROTECTION - GENERAL › Chapter 424 - LEAD MANAGEMENT REGULATIONS › Appendix 096-424-D - Lead-Based Paint Inspection Protocol

Current through 2024-29, July 17, 2024
1. Introduction
A. XRF performance characteristic sheets and
				  manufacturer's instructions.
When an XRF instrument is used for testing
				  paint in residential dwellings and pre-1978 child occupied facilities, it must
				  have a HUD -issued XRF Performance Characteristic Sheet (PCS). XRFs must be
				  used in accordance with the manufacturer's instructions and the PCS. The PCS
				  contains information about XRF readings taken on specific substrates,
				  calibration check tolerances, interpretation of XRF readings, and other aspects
				  of the model's performance.
(1) If discrepancies exist among the PCS, the most stringent
				  guidelines should be followed. For example, if the PCS has a lower (more
				  stringent) calibration check tolerance than the manufacturer's instructions,
				  the PCS should be followed.
2. Inspections in Single-Family Housing.
List
				  all testing combinations or each individual surface or component including
				  those that are painted, stained, shellacked, varnished, coated, or wallpaper
				  which covers painted surfaces.
A. Select testing combinations
(1) Perform XRF testing (including the calibration check
				  readings).
(2) Collect and analyze paint-chip samples for testing
				  combinations that cannot be tested with XRF, that have inconclusive XRF
				  results, or for client-approved confirmation of XRF results.
(3) Classify XRF and paint-chip results.
(4) Evaluate the work and results to ensure the quality of
				  the paint inspection.
(5) Document all findings in a report at a minimum meeting
				  the requirements of Section
				  7(A)(3).
B. Listing testing combinations.
Develop a list
				  of all testing combinations in all interior rooms, on all exterior building
				  surfaces, and on surfaces in other exterior areas, and fences, playground
				  equipment, and garages as applicable. An inventory of a house may be completed
				  either before any testing or on a room-by-room basis during testing.
C. Number of room equivalents to inspect.
Test
				  all room equivalents inside and outside the dwelling unit. The final report
				  must include a final determination of the presence or absence of lead-based
				  paint on each testing combination in each room equivalent. For varnished,
				  stained, or similar clear-coated floors, measurements in only one room
				  equivalent are permissible if it appears that the floors in the other room
				  equivalents have the same coating.
(1) Some testing combinations have multiple parts. For
				  example, a window testing combination could theoretically be broken down into
				  the interior sill (stool), exterior sill, trough, sash, apron, parting bead,
				  stop bead, casing, and so on. Because it is highly unlikely that all these
				  parts will have different painting histories, usually they should not be
				  considered separate testing combinations unless their professional judgment and
				  field condition dictate otherwise. (Inspectors should regard parts of building
				  components as separate testing combinations if they have evidence that
				  different parts have separate, distinct painting histories). Windows and doors
				  would typically have at least two combinations, interior and exterior.
D. Number of testing combinations to inspect.
Inspect each testing combination in each room equivalent, unless similar
				  building component types with identical substrates (such as windows) are all
				  found to contain lead-based paint in the first five interior room equivalents.
				  In that case, testing of that component type in the remaining room equivalents
				  may be discontinued,
if and only if
the purchaser of the
				  inspection services agrees beforehand to such a discontinuation. The inspector
				  should then conclude that similar building component types in the rest of the
				  dwelling unit also contain lead-based paint. For example, if an inspector finds
				  that baseboards in the first five room equivalents are all positive, the
				  inspector - with the client's permission - may conclude that all remaining room
				  equivalents in the unit contain positive baseboards. This is sometimes referred
				  to as a "positive stop."
(1) Because it is highly unlikely that testing combinations
known
(and not just presumed) to have been replaced or added
				  to the building after 1977 will contain lead-based paint, they need not be
				  tested. If the age of the testing combination is in doubt, it should be
				  tested.
E. Building component types.
Results of an
				  inspection may be summarized by classifying component types across room
				  equivalents if patterns or trends are supported by the data.
F. Substrates.
Several types of XRF instruments
				  do not require "substrate correction," needed to correct a systematic bias in
				  an XRF instrument resulting from interference from substrate material beneath
				  the paint. However, all substrates across all room equivalents should be
				  grouped into one of the six substrate categories (brick, concrete, drywall,
				  metal, plaster, or wood) shown on the XRF Performance Characteristic Sheet for
				  the instrument being used. Substrate correction procedures, if required, can
				  then be applied for all building component types with the same substrate. For
				  example, the substrate correction procedure for wooden doors and wooden
				  baseboards can use the same substrate correction value.
3. Number and Location of XRF Readings
A. Number of XRF readings for each testing combination.
XRF testing is required for at least one location per testing
				  combination, except for interior and exterior walls, where four readings should
				  be taken, one on each wall. Multiple readings on the same testing combination
				  or testing location are, therefore, unnecessary, except for interior and
				  exterior walls.
(1) Because of the large surface areas and quantities of
				  paint involved, and the possibility of increased spatial variation, take at
				  least four readings (one reading on each wall) in each room equivalent. (For
				  room equivalents with fewer than four walls, test each wall.) For each set of
				  walls with the same painting history in a room equivalent, test the four
				  largest walls. Classify each wall based on its individual XRF reading. If a
				  room equivalent has more than four walls, calculate the average of the
				  readings, round the result to the same number of decimal places as the XRF
				  instrument displays, and classify the remaining walls with the same painting
				  history as the tested walls, based on this rounded average. When the remaining
				  walls in a room equivalent clearly do not have the same painting history as
				  that of the tested walls, test and classify the remaining walls individually.
				  For exterior walls, select at least four sides and average the readings
				  (rounding the result as described above) to obtain a result for any remaining
				  sides. If there are more than four walls and the results of the tested walls do
				  not follow a classification pattern (for example, one is positive and the other
				  three are negative), test each wall individually.
B. Location of XRF readings.
The selection of
				  the test location for a specific testing combination should be representative
				  of the paint over the areas that are most likely to be coated with old paint or
				  other lead-based coatings. Thus, locations where the paint appears to be
				  thickest should be selected. Locations where paint has worn away or been
				  scraped off should not be selected. Areas over pipes, electrical surfaces,
				  nails, and other possible interferences should also be avoided if possible. All
				  layers of paint should be included, and the XRF probe faceplate should be able
				  to lie flat against the surface of the test location.
(1) If no acceptable location for XRF testing exists for a
				  given testing combination, a paint-chip sample should be collected and sent to
				  a lead laboratory recognized by NLLAP for analysis of lead in paint. The sample
				  should include all paint layers and should be taken as unobtrusively as
				  possible. Because paint-chip sampling is destructive, a single sample may be
				  collected from a wall and used to characterize the other walls in a room
				  equivalent. For greater reliability, consider collection and analysis of more
				  than one sample.
4. Documentation of XRF Reading Locations.
Descriptions of testing combinations must be sufficiently detailed to permit
				  another individual to find them. While it is not necessary to document the
exact
spot or the
exact
building component on
				  which the reading was taken, it is necessary to record the
exact
testing combination measured. Current room uses or colors can change
				  and should not be the only way of identifying them. A numbering system, floor
				  plan, sketch, or other system, is to be used to document which testing
				  combinations were tested.
A. Side identification.
Identify perimeter wall
				  sides with letters, numbers, or Roman numerals. For example, Side A for
				  single-family housing is the street side for the address. Side A in
				  multi-family housing is the apartment entry door side. Side B, C, and D are
				  identified clockwise from Side A as one faces the dwelling unit; thus, Wall B
				  is to the left, Wall C is across from Side A, and Side D is to the right of
				  Side A. Each room equivalent's side identification follows the scheme for the
				  whole housing unit. Because a room can have two or more entries, sides should
				  not be allocated based on the entry point. For example, giving a closet a side
				  allocation based on how the room is entered would make it difficult for another
				  person to make an easy identification, especially if the room had two closets
				  and two entryways.
B. Room equivalent identification.
Room
				  equivalents should be identified by both a number and a use pattern (for
				  example, Room 5-Kitchen). Room 1 can always be the first room, at the A-D
				  junction at the entryway, or it can be the exterior. Rooms are consecutively
				  numbered clockwise. If multiple closets exist, they are given the side
				  allocation: for example, Room 3, Side C Closet. The exterior is always assigned
				  a separate room equivalent identifier.
C. Sides in a room.
Sides in an interior room
				  equivalent follow the overall housing unit side allocation. Therefore, when
				  standing in any four-sided room facing Side C, the room's Side A will always be
				  to the rear, Side B will be to the left, and Side D will be to the
				  right.
D. Building component identification.
Individual
				  building components are first identified by their room number and side
				  allocation (for example, the radiator in Room 1, Side B is easily identified).
				  If multiple similar component types are in a room (for example, three windows),
				  they are differentiated from each other by side allocation. If multiple
				  components are on the same wall side, they are differentiated by being numbered
				  left to right when facing the components. For example, three windows on Wall D
				  are identified as windows D1, D2, and D3, left to right. If window D3 has the
				  only old original sash, it is considered a separate testing combination from
				  the other two windows. Codes or abbreviations for building components and/or
				  locations may be used in order to shorten the time needed for data entry. If
				  codes or abbreviations are used, the inspection records and the inspection
				  report must include a table showing their meaning.
(1) A sketch of the dwelling unit's floor plan is required by
				  this protocol. Whatever documentation is used, a description of the room
				  equivalent and testing combination identification system must be included in
				  the final inspection report.
5. XRF Calibration Check Readings.
In addition
				  to the manufacturer's recommended warm up and quality control procedures, the
				  XRF operator should take the quality control readings recommended below, unless
				  these are less stringent than the manufacturer's instructions. Quality control
				  for XRF instruments involves readings to check calibration. Most XRFs cannot be
				  calibrated on-site; actual calibration can only be accomplished in the
				  factory.
A. Frequency and number of calibration checks.
For each XRF instrument, two sets of XRF calibration check readings are
				  required at least every 4 hours. The first is a set of three nominal-time XRF
				  calibration check readings to be taken before the inspection begins. The second
				  occurs either after the day's inspection work has been completed, or at least
				  every 4 hours, whichever occurs first. To reduce the amount of data that would
				  be lost if the instrument were to go out of calibration between checks, and/or
				  if the manufacturer requires more frequent calibration checks, the calibration
				  check can be repeated more frequently than every 4 hours. If the XRF
				  manufacturer recommends more frequent calibration checks, the manufacturer's
				  instructions should be followed. Calibration should also be checked before the
				  XRF is turned off (for example, to replace a battery or before a lunch break)
				  and after it is turned on again. For example, if an inspection of a large house
				  took 6 hours, there would be three calibration checks: one at the beginning of
				  the inspection, another after 4 hours, and a third at the end of the
				  inspection.
(1) If the XRF is not turned off as the inspector travels
				  from one dwelling unit to the next, calibration checks do not need to be done
				  after each dwelling unit is completed. For example, in multi-family housing,
				  calibration checks do not need to be done after each dwelling unit is
				  inspected, once every 4 hours is usually adequate. Some inspectors do a
				  calibration check between units for two reasons: first, if the instrument goes
				  out of calibration during the inspection of the unit, only that unit needs to
				  be inspected, and, second, if the inspector inadvertently misses a calibration
				  check, the period between checks is less likely to exceed 4 hours.
(2) Some instruments automatically enter a "sleep" or "off"
				  state when not being used continually to prolong battery life. It is not
				  necessary to perform a calibration check before and after each "sleep" state
				  episode unless the manufacturer recommends otherwise.
B. Calibration check standard materials.
Portable XRF calibration check readings are taken on the National Institute of
				  Standards and Technology (NIST) Standard Reference Material (SRM) or NIST
				  Certified Reference Material using the nominal 1.0
				  mg/cm2 paint film (or nearly 1.0 in older sets)
				  within the SRM. The complete set of paint films can be obtained by calling
				  (301) 975-2200 or using the NIST SRM site at:
http://www.nist.gov/srm/index.cfm
.
(1) Calibration checks should be taken through the SRM paint
				  film with the film positioned at least 1 foot (0.3 meters) away from any
				  potential source of lead. The NIST SRM film should not be placed on a toolbox,
				  suitcase, or surface coated with paint, shellac, or any other coating to take
				  calibration check readings. Rather, the NIST SRM film should be attached to a
				  solid (not plywood) wooden board or another non-metal rigid substrate such as
				  drywall or attached directly to the XRF probe. The SRM should be positioned so
				  that readings of it are taken when it is more than 1 foot (0.3 meters) away
				  from a potential source of error. For example, the NIST SRM film can be placed
				  on top of a 1 foot (0.3 meters) thick piece of Styrofoam or other lead-free
				  material, as recommended by the manufacturer before taking readings.
C. Recording and interpreting calibration check
				  readings.
Each time calibration check readings are made; three readings
				  should be taken. These readings should be taken using the nominal time which
				  will be used during the inspection, selected from among those specified in the
				  PCS. The open shutter time should be adjusted, if necessary, to reflect the age
				  of the radioactive source. The readings can be recorded on the Calibration
				  Check Test Results form, or stored in the instrument's memory, and printed out
				  or transferred to a computer later. The average of the three calibration check
				  readings should be calculated, rounded to the same number of decimal places as
				  the XRF instrument displays, and recorded on the form.
(1) Large deviations from the NIST SRM value will alert the
				  inspector to problems in the instrument's performance. If the observed
				  calibration check average is outside of the acceptable calibration check
				  tolerance range specified in the instrument's PCS, the manufacturer's
				  instructions should be followed to bring the instrument back into control. A
				  successful calibration check should be obtained before additional XRF testing
				  is conducted. Readings not accompanied by successful calibration checks at the
				  beginning and end of the testing period are unreliable and should be repeated
				  after a successful calibration check has been made. If a backup XRF instrument
				  is used as a replacement, it must successfully pass the initial calibration
				  check test before retesting the affected test locations.
6. Substrate Correction.
XRF readings are
				  sometimes subject to systematic biases as a result of interference from
				  substrate material beneath the paint. The magnitude and direction of bias
				  depends on the substrate, the specific XRF instrument being used, and other
				  factors such as temperature and humidity. Results can be biased in either the
				  positive or negative direction and may be quite high.
A. When substrate correction is not required.
Some XRF instruments do not need to have their readings corrected for substrate
				  bias on any substrate. Other instruments may only need to apply substrate
				  correction procedures on specific substrates and/or when XRF results are below
				  a specific value. The
XRF Performance Characteristic Sheet
should be consulted to determine the requirements for a specific instrument and
				  each mode of operation (e.g., nominal time, or time required for intended
				  precision). XRF instruments which do not require correction for any substrate,
				  or require corrections on only a few substrates, have an advantage in that they
				  simplify and shorten the inspection process.
B. Substrate correction procedure.
XRF results
				  are corrected for substrate bias by subtracting a correction value determined
				  separately in each house for each type of substrate where lead paint values are
				  in the substrate correction range indicated on the XRF Performance
				  Characteristic Sheet (PCS). In single-family housing, the substrate correction
				  value is determined using the specific instrument(s) used in that house. The
				  correction value (formerly called "Substrate Equivalent Lead" or "SEL") is an
				  average of six XRF readings, with three taken from each of two test locations
				  that have been scraped visually clean of their paint coating. The locations
				  selected for removal of paint should have an initial XRF reading on the painted
				  surface of less than 2.5 mg/cm2, if possible. If all
				  initial readings on a substrate type are greater than 2.5
				  mg/cm2, the locations with the lowest initial
				  reading should be chosen. Because available data indicate that surfaces with
				  XRF readings in excess of about 3.0 mg/cm2 or 4.0
				  mg/cm2 are almost always coated with lead-based
				  paint, and since bleed-through of lead into the substrate may occur, or pipes
				  and similarly interfering building components may be behind the material being
				  evaluated, locations with such high readings should be avoided for substrate
				  correction.
(1) After all, XRF testing has been completed but before the
				  final calibration check test has been conducted, XRF results for each substrate
				  type should be reviewed. If any readings fall within the range for substrate
				  correction for a particular substrate, obtain the substrate correction
				  value.
(2) On each selected substrate requiring correction, two
				  different testing combinations must be chosen for paint removal and testing.
				  For example, if the readings are inconclusive for some wooden baseboards,
				  select two baseboards, each from a different room. If some wooden doors also
				  require substrate correction, the inspector should take substrate correction
				  readings on one door and one baseboard. Selecting the precise location of
				  substrate correction should be based on the inspector's ability to remove paint
				  thoroughly from the substrates, the similarity of the substrates, and their
				  accessibility. The XRF probe faceplate must be able to be placed over the
				  scraped area, which should be completely free of paint or other
				  coatings.
(3) The size of the area from which paint is taken depends on
				  the size of the analytical area of the XRF probe faceplate; normally, the area
				  is specified by the manufacturer. To ensure that no paint is included in the
				  bare substrate measurement, the bare area on the substrate should be slightly
				  larger than the analytical area on the XRF probe faceplate.
(4)In all, six readings must be taken for each substrate type
				  that requires correction. All six must be averaged together. Take three
				  readings on the first bare substrate area. Record the substrate and XRF
				  readings on the "Substrate Correction Values" form. Repeat this procedure for
				  the second
bare
substrate area and record the three readings
				  on the same form. Substrate correction values should be determined using the
				  same instrument used to take readings on the painted surfaces. If more than one
				  XRF model was used to take readings, apply the substrate correction values as
				  specified on each instrument's PCS.
(5) Compute the correction value for each substrate type that
				  requires correction by computing the average of all six readings as shown below
				  and recording the results on the "Substrate Correction Values" form. The
				  formula given below should be used to compute the substrate bias correction
				  value for XRF readings taken on a bare substrate that is not covered with NIST
				  SRM film. A different formula should be used when SRM film must be placed over
				  the bare substrate. The PCS specifies when this correction is necessary and
				  provides the formula for computing the correction value.
(6)
Negative values.
If more than 20 percent of
				  the corrected values are negative, the instrument's lead paint readings and/or
				  the substrate readings are probably in error. Calibration should be checked,
				  and substrate measurements should be repeated.
(7)
Discarding readings.
If the manufacturer's
				  instructions call for the deletion of readings at specific times,
only
readings taken at those specific times should be deleted.
				  Similarly, readings between a successful calibration check and a subsequent
				  unsuccessful calibration check must be discarded. Readings should not be
				  deleted based on any criteria other than what is specified by the
				  manufacturer's instructions.For example, a manufacturer may instruct operators
				  to discard the first XRF reading after a substrate change. If so,
only
the first reading should be discarded after a substrate
				  change.
7. Classification of XRF Results.
XRF results
				  are classified as positive, negative, or inconclusive.
A. A positive
classification indicates that lead
				  is present on the testing combination at or above the standard of 1.0
				  mg/cm2. A positive XRF result is any value greater
				  than the upper bound of the inconclusive range, or greater than or equal to the
				  threshold, as specified on the applicable XRF Performance Characteristic Sheet
				  (PCS).
B. A negative
classification indicates that lead
				  is not present on the testing combination at or above the standard. A negative
				  XRF result is any value less than the lower bound of the inconclusive range, or
				  less than the threshold, specified on the PCS.
C. An inconclusive
classification indicates that
				  the XRF cannot determine with reasonable certainty whether lead is present on
				  the testing combination at or above the standard. An inconclusive XRF result is
				  any value falling within the inconclusive range on the PCS (including the
				  boundary values defining the range). In single-family housing, all inconclusive
				  results should be confirmed by analysis by a laboratory recognized by EPA,
				  under NLLAP, for analysis of lead in paint, unless the client wishes to assume
				  that all inconclusive results are positive.
D. Positive, negative, and inconclusive
results
				  apply to the actual testing combination and to any repetitions of the testing
				  combination that were not tested in the room equivalents. Positive results also
				  apply to similar component types in room equivalents that were not tested. For
				  example, suppose that one baseboard in a room equivalent is tested, and that
				  the inspector decided that all four baseboards are a single testing
				  combination. The single XRF result applies to all four baseboards in that room
				  equivalent.
E.
When an inconclusive range is specified on
				  the PCS, the inconclusive range includes its upper and lower bounds. XRF
				  results are classified as positive if they are greater than the upper boundary
				  of the inconclusive range, negative if they are less than the lower boundary of
				  the inconclusive range, or inconclusive otherwise.
F.
Different XRF models have different
				  inconclusive ranges, depending on the specific XRF model and the mode of
				  operation. The inconclusive range may also be substrate specific. In some
				  cases, the upper and lower limits of the inconclusive range are equal; that
				  value is called the
threshold.
If the reading is less than the
				  threshold, then the reading is considered negative. If the reading is equal to
				  or greater than the threshold, then the reading is considered positive. Use of
				  the inconclusive range and threshold is detailed in the performance
				  characteristic sheet. The categories include substrate-corrected results, if
				  substrate correction is indicated. XRFs with
only
threshold
				  values listed on the PCS are advantageous in that classifications of results
				  are either positive or negative (no XRF readings are inconclusive). Note that
				  the final inspection report should not list inconclusive readings as a third
				  category in addition to positive and negative. There are two options for
				  addressing inconclusive readings:
(1) A paint chip may be sampled and sent to a laboratory
				  recognized by EPA, under NLLAP, for analysis of lead in paint.
(2) If the client agrees, all inconclusive readings may be
				  assumed to be positive. It is not permissible to assume any inconclusive
				  reading is negative.
8. Evaluation of the Quality of the
				  Inspection
A. Repeated testing of ten surfaces.
Data from
				  HUD's private housing lead-based paint hazard control program show that it is
				  possible to successfully retest painted surfaces without knowing the exact spot
				  which was tested. Select 10 testing combinations at random from the already
				  compiled list in the "Single-Family Housing LBP Testing Data Sheet" for
				  retesting. If possible, the same XRF instrument used in the original inspection
				  should be used in the retesting. If the XRF instrument used in the original
				  inspection is not available and cannot be returned to the site, use an XRF of
				  the same model for retesting. Use the same procedures to retest the 10 testing
				  combinations. The 10 repeat XRF results are compared with the 10 XRF results
				  previously made on the same testing combinations.
(1) The repeat readings and the original readings should not
				  be corrected for substrate bias for the purpose of this comparison. The average
				  of the 10 repeat XRF results should not differ from the 10 original XRF results
				  by more than the retest tolerance limit. The procedure for calculating the
				  retest tolerance limit is specified in the PCS.If the limit is exceeded, the
				  procedure should be repeated using 10 different testing combinations. If the
				  retest tolerance limit is exceeded again, the original inspection is considered
				  deficient.
9. Inspections in Multi-family Housing.
For
				  inspection purposes only, multi-family housing is defined as any group of more
				  than four units that are similar in construction from unit to unit.
Selection of housing units, common areas, and exterior
				  site areas.
The first step in selecting housing units is to identify
				  buildings in the development with a common construction based on written
				  documentation or visual evidence of construction type. Such buildings can be
				  grouped together for sampling purposes. For example, if two buildings in the
				  development were built at the same time by the same builder and appear to be of
				  similar construction, all of the units in the two buildings can be grouped for
				  sampling purposes, as can the common areas, and exterior site areas. Units can
				  have different sizes, floor plans, and number of bedrooms and still be
				  grouped.
Number of Units to be Tested in Multi-family Building
				  or Developments
Number of Similar Units, Similar
							 Common Areas, or Similar Exterior Sites
Pre-1960 or Unknown-Age Building or
							 Development: Number of Units to Test
1960-1977 Building or Development:
							 Number of Units to Test
1-10
All
All
11-13
All
10
14
All
10
15
All
12
16-17
All
13
18
All
14
19
All
15
20
All
16
21-26
20
16
27
21
17
28
22
18
29
23
18
30
23
19
31
24
19
32
25
19
33-34
26
19
35
27
19
36
28
19
37
29
19
38-39
30
20
40-48
31
21
49-50
31
22
51
32
22
52-53
33
22
54
34
22
55-56
35
22
57-58
36
22
59
37
23
60-69
38
23
70-73
38
24
74-75
39
24
76-77
40
24
78-79
41
24
80-88
42
24
89-95
42
25
96-97
43
25
98-99
44
25
100-109
45
25
110-117
45
26
118-119
46
26
120-138
47
26
139-157
48
26
158-159
49
26
160-177
49
27
178-197
50
27
198-218
51
27
219-258
52
27
259-279
53
27
280-299
53
28
300-379
54
28
380-499
55
28
500-776
56
28
777-939
57
28
940-1004
57
29
1005-1022
58
29
1023-1032
59
29
1033-1039
59
30
1500
87
44
2000
116
58
2500
145
73
3000
174
87
3500
203
102
4000
232
116
(1) The specific units to be tested should be chosen randomly
				  from a list of all units in each building or buildings. (For brevity, just
				  "units" are mentioned in describing the random selection procedure, but the
				  procedure is the same for similar units, similar common areas, and similar
				  exterior sites.) The "Selection of Units" form or a comparable form may be used
				  to aid in the selection process. A complete list of all units in each group
				  should be used and a separate identifying sequential number must be assigned to
				  each unit. For example, if apartment addresses are shown as 1A, 1B, 2A, 2B
				  etc., they must be given a sequence number (1, 2, 3, 4, etc.).
Note
: Units without identifiers
				  cannot not be selected for inspection and would bias the sampling. The list of
				  units should be complete and verified by consulting building plans or by a
				  physical inspection of the development.
(2) Specific units to be tested should be selected
				  randomly.
Note
: Tables of random numbers
				  are often included in statistics books. Today's common full-function computer
				  spreadsheet software products have random number generator functions of
				  sufficient quality for use in lead-based paint inspections.
In Microsoft Excel the code = RAND BETWEEN (X,Y), where X is
				  the first unit number in the list and Y is the final unit number in the list,
				  will generate a random whole number that can be used to randomly select a unit
				  for sampling. The Rand between function is also available in other software,
				  such as Open Office.
Inspectors are, therefore, advised to use them to obtain the
				  random numbers, which can then be used to select the specific numbered
				  units.
(a) The "Selection of Units" form is completed by filling in
				  as many random numbers as are needed in the appropriate column. Numbers for the
				  third column are obtained by multiplying the total development size by each
				  random number. Numbers for the fourth column are obtained by rounding up from
				  the previous calculation to the next whole number. If the whole number in the
				  fourth column has already been selected, that selection should not be entered
				  again. The notation "DUP" should be entered to show that the selection was a
				  duplicate. This process should continue until the required number of distinct
				  sample numbers has been selected. Common areas and exterior room equivalents
				  should be identified at this time, but they are not considered to be separate
				  units.
B. Listing testing combinations and common
				  areas.
The "Multi-family Housing LBP Testing Data Sheet" form or a
				  comparable form should be used to list the testing combinations in each unit,
				  common area and exterior site that was selected for inspection. In multi-family
				  housing, the inventory of testing combinations often will be similar for units
				  that have the same number of bedrooms. The inspector should, however, list
				  testing combinations that are unique to each tested unit. For example, some
				  units may contain built-in cabinets while others do not. The selection of
				  testing combinations should, therefore, be carried out independently in each
				  inspected unit.
(1) As in single family housing, take readings on all testing
				  combinations in all room equivalents in each unit selected for testing.
				  However, common areas need to be identified and tested as well.
C. Common areas.
Similar common areas and
				  similar exterior sites must always be tested, but in some cases, they can be
				  sampled in much the same way that dwelling units are. Common areas and building
				  exteriors typically have a similar painting history from one building to the
				  next. In multi-family housing, each common area (such as a building lobby,
				  laundry room, or hallway) can be treated like a dwelling unit. If there are
				  multiple similar common areas, they may be grouped for sampling purposes in
				  exactly the same way as regular dwelling units are. However, dwelling units,
				  common areas and exterior sites cannot all be mixed together in a single
				  group.
(1) All testing combinations within each common area or on
				  building exteriors selected for testing must be inspected. This includes
				  playground equipment, benches and miscellaneous testing combinations located
				  throughout the development. The specific common areas and building exteriors to
				  test should be randomly selected, in much the same way as specific units are
				  selected using random numbers.
(2) The number of common areas to test should be taken from
				  the above table. In this instance, common areas and building exteriors can be
				  treated in the same way as housing units (although they are not to be confused
				  with true housing units).
10. Classification of XRF Results in Multi-family
				  Housing.
The inspector should record each XRF reading for each testing
				  combination on the "Multi-family Housing LBP Testing Data Sheet," or a
				  comparable form, and indicate whether that testing combination was classified
				  as positive, negative, or inconclusive as described previously for
				  single-family housing.
A.
When the inspection is completed in all the
				  selected units and the classification rules have been applied to all XRF
				  results, the HUD "Multi-family Housing: Component Type Report" form or a
				  comparable form should be completed. Building component types groups of like
				  components constructed of the same substrate in the multi-family housing
				  development are aggregated on this form. For example, grouping all interior
				  walls would create an appropriate component type if all walls are plaster.
				  Grouping all doors would not be appropriate; however, if some doors are metal
				  and some are wood. At least 40 testing combinations of a given component type
				  in a multi-family housing development must be tested to obtain the desired
				  level of confidence in the results for that component type. If fewer than 40
				  testing combinations of a given component type were tested, test additional
				  combinations of that component type. If fewer than 40 components of a given
				  type exist in the units to be tested, test all of the components that do
				  exist.
B.
In some cases, additional sampling of the
				  specific component may not be necessary. If no lead at or above the standard is
				  found on that component type, additional measurements should be taken in other
				  units to increase the sample size to 40. However, if all or most of the sampled
				  component types are positive, no further sampling is needed, provided that the
				  building owner agrees with this reduction of testing. For example, if 20 out of
				  60 doors are tested, and the majority is positive for lead-based paint, all
				  similar doors in the buildings may be presumed positive; only those doors
				  tested and found negative may be treated as negative. Note that the inspector
				  and owner may not presume a component is negative. All required XRF testing
				  and/or laboratory analysis must be completed to conclude that any or all
				  components included in a given component type are negative.
C.
The substrate and the component for each
				  component type should be recorded on the HUD "Multi-family Housing: Component
				  Type Report" or comparable form under the heading "Description" (for example,
				  wooden interior doors), as should the total number of testing combinations
				  included in the component type. In addition, for each component type, the
				  aggregated positive, negative, and inconclusive classifications should be
				  recorded as described below. Record the number and percentage of testing
				  combinations classified as:
(1) Positive for lead-based paint. This is based upon a
				  positive XRF reading in accordance with the XRF's Performance Characteristic
				  Sheet;
(2) Low Inconclusive for lead-based paint. This is based on
				  having XRF readings less than the midpoint of the XRF's inconclusive range (if
				  the XRF instrument does not have an inconclusive range (that is, it has a
				  threshold value), this aggregation element should not be provided);
(3) High Inconclusive (high) for lead-based paint. This is
				  based on having XRF readings equal to or greater than the midpoint of the XRF's
				  inconclusive range (if the XRF instrument does not have an inconclusive range
				  (that is, it has a threshold value), this aggregation element should not be
				  provided); and
(4) Negative for lead-based paint.
(5) Positive: Lead-based paint is present on one or more of
				  the components.
(6) Negative: Lead-based paint is not present on the
				  components throughout the development. (Lead may still be present at lower
				  loadings and hazardous leaded dust may be generated during modernization,
				  renovation, repair, remodeling, maintenance, painting or other disturbances of
				  painted surfaces.)
D.
The decision that lead-based paint is not
				  present throughout the development is reached if:
(1) 100 percent of the tested component types are negative,
				  or
(2) 100 percent of the tested component types are classified
				  as either negative or inconclusive
and
all of the inconclusive
				  classifications have XRF readings less than the midpoint of the inconclusive
				  range for the XRF in use.
(3) Note: that the midpoint of the inconclusive range is
not
a threshold; it is used only for classifying XRF readings
				  in multi-family housing in conjunction with information about other XRF
				  readings as described here.
(4) For cases with greater than or equal to 5% positives
and
less than 15% positives, as well as no positives but
				  greater than 15% high inconclusive, some confirmatory laboratory testing may be
				  needed to reach a final conclusion, unless the client wishes to assume the
				  validity of the XRF results and that all inconclusive are positive.
(a) For each testing combination with an inconclusive XRF
				  reading at or above the midpoint of the inconclusive range, a paint-chip sample
				  should be analyzed by a laboratory recognized by the EPA NLLAP for the analysis
				  of lead in paint.
(b) If all the laboratory-analyzed samples are negative, it
				  is not necessary to test inconclusive XRF results below the midpoint of the
				  inconclusive range.
(c) If, however,
any
laboratory results are
				  positive on a component type, all inconclusive equal to or above the midpoint
				  of the inconclusive range should be analyzed, or they should be presumed to be
				  positive.
(d) Percentages of positive or inconclusive results are
				  computed by dividing the number in each classification group by the total
				  number of testing combinations of the component type that were tested. For
				  example, if 245 wooden doors in a multi-family housing development were tested
				  and 69 were classified as inconclusive with XRF readings less than the midpoint
				  of the inconclusive range, 28 percent [(69 / 245) x 100 percent = 28.2 percent]
				  should be recorded on the form in the "<1.0 percent" columns under the
				  heading "Inconclusive."
11. Unsampled Housing Units.
If a particular
				  component type in the sampled units is classified as positive, that same
				  component type in the un-sampled units is also classified as positive. For
				  those cases where the number of positive components is small, further analysis
				  may determine if there is a systematic reason for the specific mixture of
				  positive and negative results.
Note
: For example, suppose that
				  a few porch railings tested negative, but most tested positive. Examination of
				  the sample results in conjunction with the building records showed that the
				  porch railings classified as positive were all original and the railings
				  classified as negative were all recent replacements. The records did not reveal
				  which units had replaced railings, and due to historic preservation
				  requirements, the replacement railings were identical in appearance to the old
				  railings. Thus, all un-sampled original porch railings could be classified as
				  positive, and all un-sampled recently replaced porch railings could be
				  classified as negative if at least 40 of the replaced porch railings had been
				  tested or were determined to have been installed after 1978.
A. Fewer than 5% positive results.
Where a small
				  fraction of XRF readings, less than 5% percent, of a particular component type
				  are positive, several choices are available:
(1) First, the inspector may confirm the results by
				  laboratory analysis, which is considered definitive when performed; a
				  laboratory lead result of 1.0 mg/cm2 or greater (or
				  0.5 percent by weight or greater) is considered positive.
(2) Second, the inspector may select a second random sample
				  (using un-sampled units only) and test the component type in those units. If
				  less than 2.5% of the combined set of results is positive, the component type
				  may be considered as having lead-based paint in isolated locations, but not
				  having lead-based paint development-wide, with a reasonable degree of
				  confidence. Individual components that are classified positive should be
				  considered as being lead-based painted and managed or abated
				  appropriately.
(3) Finally, if the client chooses not to confirm the results
				  by laboratory analysis and not to take a second set of measurements, then the
				  component type should be considered as having lead-based paint
				  development-wide. The inspector may wish to advise the client that the cost of
				  additional XRF testing or laboratory analysis is usually much less than the
				  cost of lead abatement or interim control projects. This is of particular
				  interest in the situation where few results are positive, because there is a
				  significant chance that the paint, development-wide, may not be
				  lead-based.
B.