ASTM E2120-10(2016)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E2120 − 10 (Reapproved 2016)
Standard Practice for
Performance Evaluation of the Portable X-Ray Fluorescence
Spectrometer for the Measurement of Lead in Paint Films
This standard is issued under the fixed designation E2120; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.2 ANSI Standards:
ANSIN538–1979Classification of Industrial Ionizing Ra-
1.1 This practice covers portable X-ray fluorescence (XRF)
diation Gauging Devices
instrumentsintendedforthemeasurementofleadinpaint.Itis
ANSIN323–1978RadiationProtectionInstrumentationTest
intended that manufacturers apply this practice to one unit of a
and Calibration
particular model of an instrument when that model is initially
2.3 ISO Standards:
available.Replicatetestsonadditionalunitsofthesamemodel
ISO 2919 Radiation Protection – Sealed Radioactive
of an instrument are to be performed at the discretion of the
Sources – General Requirements and Classification
manufacturer. This practice also is intended for use by third
2.4 UL Standards:
parties performing independent evaluation of portable X-ray
UL544Safety for Medical andDental Equipment
fluorescence instruments.
UL3101–1 Chemical Analyzers
1.2 All performance evaluation data are to be in SI units.
3. Terminology
1.3 Tests of performance are based on replicate measure-
mentsofcertifiedreferencepaintfilmsonavarietyofsubstrate 3.1 Definitions:
materials. Tests are performed to determine: bias, precision, 3.1.1 accuracy, n—the theoretical maximum error of a
linearity,limitofdetection,interferences,substrateaffects,and measurement, expressed as the proportion of the amount being
stability. measured without regard for the direction of the error, that is
achieved with a given probability (typically 0.95) by the
1.4 This standard does not purport to address all of the
method.
safety concerns, if any, associated with its use. It is the
3.1.2 bias, n—the discrepancy between the mean of the
responsibility of the user of this standard to establish appro-
distribution of measurements from a method and the true
priate safety and health practices and determine the applica-
concentration being measured.
bility of regulatory limitations prior to use.
3.1.3 limit of detection, n—the smallest (true) signal that
2. Referenced Documents
willbedetectedwithaprobability1–β(βistheprobabilityof
an error of the second kind, failing to decide that a substance
2.1 ASTM Standards:
is present when it is), where the a posteriori decision mecha-
D3332Test Methods for Mechanical-Shock Fragility of
nismhasabuilt-inprotectionlevel,α(αistheprobabilityofan
Products, Using Shock Machines
error of the first kind, deciding that the substance is present
E344Terminology Relating to Thermometry and Hydrom-
when it is not), against falsely concluding that a blank
etry
observation represents a “real” signal. The β and α terms
E456Terminology Relating to Quality and Statistics
typicallyare5%or1%,dependingontherequirementsofthe
E1605Terminology Relating to Lead in Buildings
testing program.
1 3
ThispracticeisunderthejurisdictionofASTMCommitteeD22onAirQuality Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
and is the direct responsibility of Subcommittee D22.12 on Sampling andAnalysis, 4th Floor, New York, NY 10036, http://www.ansi.org.
of Lead, for Exposure and Risk Assessment. Available from Underwriters Laboratories (UL), 333 Pfingsten Rd.,
Current edition approved March 1, 2016. Published June 2016. Originally Northbrook, IL 60062-2096, http://www.ul.com.
approved in 1999 as PS116–99. Last previous edition approved in 2010 as Kennedy, E.R., T.J. Fischbach, R. Song, P.M. Miller, and S.A. Shulman,
E2120–10. DOI: 10.1520/E2120-10R16 Guidelines for Air Sampling and Analytical Method Development and Evaluation,
For referenced ASTM standards, visit the ASTM website, www.astm.org, or DHHS(NIOSH)PublicationNo.95–117.NationalInstituteforOccupationalSafety
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM and Health, Cincinnati, OH 45226, May 1995.
Standards volume information, refer to the standard’s Document Summary page on Currie, L.A., “Limits for Qualitative Detection and Quantitative
the ASTM website. Determination,” Analytical Chemistry, Vol 40, No. 3, 1968, pp. 586–593.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2120 − 10 (2016)
3.1.4 precision, n—the closeness of agreement between
(Film 1) <0.2x
(Film 2) 0.2x to 0.5x
repetitivetestresultsobtainedunderprescribedconditions(see
(Film 3) 0.7x to 1.3x
TerminologyE456).Theprecisionofasingleinstrumentisthe
(Film 4) 1.5x to 2x
random component of its accuracy and is usually indicated by
(Film 5) >2x
the value of the standard deviation.
3.3.8.1 Discussion—An example CRM in use is the NIST
Standard Reference Material (SRM) 2579, which consists of
3.2 ThedefinitionsgiveninTerminologiesE344andE1605
five films at <0.0001, 0.29, 1.02, 1.63 and 3.53 mg Pb/cm ,
shall apply to this practice.
respectively.
3.3 Definitions of Terms Specific to This Standard:
NOTE1—ThesupplyofNISTSRM2579standardpaintfilmsisnow(as
3.3.1 battery charger, n—a means for recharging a portable
of1998)exhausted,thoughitislikelythatthisSRMwillbereplacedwith
instrument’s self-contained battery pack, usually converting
a new SRM. CRMs from NIST or commercial vendors may be used in
110 VAC to low level DC power.
place of NIST SRM 2579, provided the action level of concern, for
example, HUD action level of 1.0 mg/cm , is represented by one of the
3.3.2 cycle or reading time, n—a period of X-ray data
new films.
collection (counting) performed automatically by some instru-
3.3.9 stray radiation, n—the sum of leakage and scattered
ments. Such time may be established by a standardization
radiation as measured according to 7.1.8.
procedure that would adjust for variation in the strength of the
3.3.10 useful beam, n—radiation that passes through the
radioactive source. Also, it might be adjustable on some
window aperture, cone, or other collimating device of the
instruments to achieve different levels of measurement preci-
source housing; sometimes called primary beam.
sion. Depending on the instrument model, one “cycle time”
may be equivalent to one “measurement time” or several
3.3.11 X-ray detector, n—a device that generates an elec-
“cycles” may be automatically or manually averaged to equal
tronic signal as a result of the interception of an X-ray.
one “measurement time.” The time begins with the opening of Examples include gas proportional counters, for example, Xe,
the XRF instrument shutter to expose the paint film surface to
solid scintillation counters, for example, CsI, and semiconduc-
the source radiation and is concluded when the source shutter tor devices of elemental, for example, Si or Ge, or compound,
for example, HgI , CdTe, or CdZnTe, composition.
is closed.
3.3.3 display unit, n—an electronic device that presents the
4. Summary of Practice
results of the measurement to the user. Other parameters such
4.1 The X-ray instrument is evaluated with respect to a
as total measurement time also may be presented.
series of manufacturer’s requirements for bias, precision,
3.3.4 measurement time, n—the duration of a single mea-
effects of environment, data display, battery operation,
surement observed in real time.Ameasurement may comprise
construction, markings, and documentation. The performance
several individual readings or cycles.
of the instrument is evaluated in the laboratory by measuring a
3.3.5 measurement value, n—the readout of a lead concen- series of standard lead-containing paint films placed on a wide
tration in mg/cm obtained at the end of one cycle time (or variety of different substrate materials. Data from replicate
measurements and comparison of measured and expected
several cycle times if multiple readings are averaged) or at the
end of one measurement time. values are then used to determine bias, precision, limit of
detection, linearity, interferences, substrate effects, and stabil-
3.3.6 probe, n—a hand-held device containing the radioac-
ity; radiation safety is evaluated, as well.
tive source, X-ray detector, and associated mechanical and
electrical components that is placed against the test sample to
5. Significance and Use
perform the measurement. The probe may constitute a part or
5.1 TheXRFinstrumentisusedtomeasuretheleadcontent
all of the XRF instrument.
in paint films in buildings and related structures in order to
3.3.7 radioactive source, n—a radioactive material (for
determine the potential lead hazard and the possible need for
57 109 241
example, Co, Cd,and Am)thatemitsX-raysorgamma
in-place control or abatement, or both.
rays that serve to cause ionization of the lead atoms in the
5.2 This practice also is to be used for the laboratory
sample, and subsequently a cascade of higher energy electrons
evaluation of the performance of portable X-ray fluorescence
intothevacatedlowerenergyshells.Astheseelectronsfallinto
instrumentation.
the lower energy orbitals, they emit energy in the form of
X-rays that are characteristic of lead.
5.3 This practice is to be used as a guide for determining
that the manufacturer of portable X-ray instrumentation has
3.3.8 standard paint films, n—free-standing, certified refer-
met certain requirements, most of which deal with instrument
ence paint films, that is, certified reference materials (CRMs),
construction.
that are acquired from the National Institute of Standards and
Technology(NIST)oracommercialvendor.Theleadlevelsin 5.4 The evaluation may be performed by the manufacturer,
thestandardpaintfilms(CRMs)shallbebasedon“x”levelfor
or an independent party. The results may be presented to
leadwhere“x”isequaltotheappropriatelocal,state,orfederal various government agencies and, upon request, potential
action level for lead in coatings (in mg/cm of lead coating). purchasersandusersoftheinstrumentation.Allorpartsofthis
The paint films shall be as follows: practice also may be performed by an X-ray instrument
E2120 − 10 (2016)
owner/user to determine the acceptability of an instrument or performance of the device may be degraded should one or
whether the performance of an instrument continues to be more of the following occur:
acceptable, or both. (1)Operation outside the manufacturer’s stated tempera-
ture and humidity range.
5.5 This practice may be used by field testers for quality
(2)Storage outside the manufacturer’s stated temperature
control by performing selected activities described in the
and humidity range.
document on a regular and recurring basis in a manner similar
(3)Mechanical shock equivalent to hitting the probe or
to those protocols followed by users of laboratory instruments.
displayunitagainstadoorframeorsimilarobject,ordropping
5.6 Limitation—Bias and precision, as determined in the
either more than a distance of 30 cm (1 ft).
laboratorybythispractice,togetherprovideonlyanestimateof
NOTE 2—The critical velocity, V , which is the velocity at which
c
the accuracy that may be achieved in the field.Accuracy in the
product failure just begins to occur, may be determined using Test
fieldwilldependupontheinstrumentcalibration,theformand
Methods D3332. (Formal procedure for testing for failure due to rapid
composition of the substrate, the structure of the paint film
change in the velocity occurring from collision.)
being analyzed, as well as other factors.
6.1.5 Data Display Resolution—The digital data display
shall have incremental steps not greater than 0.1 mg/cm ; that
6. Requirements
is, a resolution of at least 60.1 mg/cm .
6.1 Unless otherwise specified, the following requirements
6.1.6 Battery Condition—When the instrument is battery
are to be met by the manufacturer of the X-ray instrument.
operated, the bias, precision, and other operational parameters
6.1.1 Bias—The manufacturer shall provide a value or
such as calibration stability shall not be affected by battery
valuesforthebiasoftheinstrumentmodelthathas[have]been
condition, unless a continuous automatic indication of unreli-
determined using the procedure presented in Section 7 of this
able battery condition is provided.The indication of unreliable
practice. This value shall be made available to potential users,
battery condition must be presented until the battery condition
and also to interested parties, for example, the U. S. Environ-
is corrected. When an instrument uses a rechargeable battery,
mental Protection Agency and the U. S. Department of
some indication shall be provided by the instrument system to
Housing and Urban Development.
indicate that the battery is charging.
6.1.2 Precision—The manufacturer shall provide a value or
6.1.7 Construction:
values for the precision of the instrument model that has been
6.1.7.1 Electrical—The instrument and accessories (such as
determined using the procedure presented in Section 7 of this
battery chargers) shall meet the electrical safety requirements
practice. This value shall be made available to potential users,
of UL544 and UL3101–1.
and also to interested parties, for example, the U. S. Environ-
6.1.7.2 The surface of the instrument including the probe,
mental Protection Agency and the U. S. Department of
controlconsole,andaccessoriesshallwithstandphysicalclean-
Housing and Urban Development.
ing using a damp cloth, HEPA vacuum, or manufacturer’s
6.1.3 Limit of Detection—The manufacturer shall provide a
recommended procedures without performance degradation.
value or values for the limit of detection of the instrument that
6.1.7.3 The instrument shall withstand a free fall of 3 m
has been determined using the procedure presented in Section
(10ft) onto a flat concrete surface at 25°C (77°F) without
7 of this practice. This value shall be made available to
evidence of mechanical or electronic failure that could present
potential users, and also to interested parties, for example, the
a radiation, or electrical safety hazard, or both. The essential
U. S. Environmental ProtectionAgency and the U. S. Depart-
criteriaforpassingsuchatestarethatthereshallbenoexternal
ment of Housing and Urban Development.
dispersal of radioactive material and that the source capsule
6.1.4 Environment:
shall remain captive in its protective source housing. Dummy
6.1.4.1 Operating Environment—The instrument shall be
sources and X-ray detection devices may be used in these
capable of meeting the manufacturer’s performance specifica-
evaluations.
tions for bias and precision when operating in an environment
of2to35°C(35to95°F)andarelativehumidityof15to95%, 6.1.7.4 Radiation—The instrument shall meet the radiation
noncondensing. safety features and requirements presented in Section 3 of
6.1.4.2 Storage Environment—The instrument shall be ca- ANSIN538–1979.
pable of meeting the manufacturer’s performance specifica- (1) Source Integrity—The radioactive material shall be in
tions for bias and precision after imposing each of the the form of a sealed source that shall be classified in accor-
following conditions: storage at 43°C (110°F) for up to one dance with ISO2919.
month; transportation for up to 12 h at a maximum of 50°C (2) Gamma and X-Ray Beam Controls—The probe shall
(120°F), with a relative humidity of 15 to 95%, noncondens- include a manual excitation beam control designed so that
ing; storage at 0°C (32°F) for up to one month; and transpor- when the source shutter is in the OFF condition, the measured
tation for up to 12 h at a maximum of –10°C (15°F). The radiation levels in the useful beam space are no greater than a
manufacturershallindicatetheperiodoftimenecessaryforthe dose rate of 50 Sv/h at 30 cm and 1000 Sv/h at 5 cm as
instrument’s batteries to be charged and for the instrument to measured in accordance with the procedures summarized in
stabilize at the measurement temperature prior to a calibration 7.1.8. A locking mechanism shall be provided to physically
check, or recalibration, if necessary. securetheradiationbeaminthefullyOFFcondition.Aneasily
6.1.4.3 Manufacturer’s Instructions—The instruction checked indicator signal, which positively indicates when the
manual shall include a statement that informs the user if the excitation-useful beam control system is not in the fully OFF
E2120 − 10 (2016)
condition, and when it is in the fully OFF condition, shall be ous performance to the requirements of 6.1.1 and 6.1.2. The
located on or adjacent to the radiation source housing. manufacturer shall provide specific instructions for the adjust-
ment of the instrument if user adjustment is permitted by the
6.1.8 Marking—All markings for purposes of identification
manufacturer. Test equipment or fixtures required for adjust-
or instruction must be clear and legible. Deterioration of the
ment must either be described in sufficient detail to permit
markings on the instrument shall not occur when subjected to
fabrication or purchase, or manufacturer’s equipment or fix-
cleaningasdescribedin6.1.7.2oraccordingtomanufacturer’s
tures must be made available to users.
procedures.
6.1.9.5 Detailed Specifications—The manufacturer shall
6.1.8.1 Instrument Marking—The instrument shall be
provide specifications of the instrument’s bias (see 6.1.1),
marked with the manufacturer’s or distributor’s name, model
precision(see6.1.2),andenvironmentallimitations(see6.1.4).
designation,andserialnumber.Italsoshallbemarkedwiththe
date of the most recent calibration of the instrument, as
7. Performance Tests
performed by the manufacturer.Alternatively, this latter infor-
7.1 This section describes apparatus and procedures for
mationmaybeprovidedinawrittendocumentthatisprovided
verifying conformance to certain performance requirements of
with the instrument.
Section 6. These tests are not required of the manufacturer
6.1.8.2 Measurement Probe—The portion of the instrument
unless specified by the user. Verification procedures are not
containing the radioactive material shall be marked with a
includedforrequirementsthatcanbeverifiedbyobservationor
durable, permanent label indicating the type and amount of
inspection, or where a standard procedure is not needed, such
radioactive material, the measurement (radio assay) date, the
as the requirements of 6.1.4.1. The manufacturer shall certify
standard radiation symbol, and a caution notice that shall read
that the product will comply with the requirements, if tested in
as follows, or similarly: CAUTION—RADIOACTIVE MA-
accordance with this section. With the exception of the
TERIAL.
potentially destructive tests, any single portable X-ray fluores-
6.1.8.3 OperatingInstructions—Operatinginstructionsshall
cence instrument shall be capable of undergoing the following
be provided with the instrument. Radiation safety warnings
tests in any sequence without impairment of performance.
must be provided on the instrument.
6.1.8.4 Care and Use Instructions—Instructions for the
NOTE 3—Bias, precision, and limit of detection, as determined by this
care, use, and physical cleaning of the instrument shall be practice, provide only estimates of the values that may be achieved in the
field.
provided.Properuseandapplicationofaccessories,suchasthe
NOTE4—Itisexpectedthatthemanufacturerwillevaluateonlyoneunit
battery charger shall be indicated.
of each model type produced and will reevaluate that model when any
6.1.8.5 Health and Safety Hazard Marking—Notices, as
changes that could affect performance are made.
required by local, state, and federal regulations, shall be NOTE 5—The performance tests described below use a fixed total
measurement time of nominally one minute. Modification of these
displayed on the instrument.
performance evaluation tests may be needed for instruments that are
6.1.8.6 Identification—Inorderthatpurchasersmayidentify
operated using variable measurement times, for example, instruments that
products conforming to all requirements of this specification,
read until the relative standard deviation of the number of X-rays counted
producers and distributors may include a statement of compli-
reaches a preset value.
ance in conjunction with their name and address on product
7.1.1 Calibration:
labels,invoices,andsalesliterature.Thefollowingstatementis
7.1.1.1 Themanufacturershallprovideageneraldescription
suggested when sufficient space is available: This X-ray
of the calibration procedure used, including the calibration
fluorescence instrument conforms to all of the requirements
range, a list of the standards used, and a list of the substrate(s)
establishedinthispractice.Fullresponsibilityforconformance
used or a description of the assumptions made regarding
of this product to the specification is assumed by (name and
substrates; conditions under which the calibration is not
address of producer or distributor).
applicable shall be presented.
6.1.9 Documentation:
7.1.1.2 The manufacturer shall provide a procedure and
6.1.9.1 Manufacturer’s Instructions—Instructions for use
either the required standards or descriptions of needed stan-
shall be provided. These instructions shall contain sufficient
dards to perform a check of the manufacturer’s calibration.
detail to provide a means for training in the operation,
This procedure shall include instructions for performance of
application, care, and physical cleaning of the instrument and
data treatment and criteria for deciding if the calibration is
accessories.
within the manufacturer’s specifications.
6.1.9.2 Service and Repair Manual—Aservicemanualshall
7.1.2 Accuracy—Accuracy may be calculated from values
be made available if user repair is permitted by the manufac-
of bias and precision using rigorous statistical procedures.
turer. The service manual shall provide theory of operation,
These procedures can be found in the NIOSH Technical
maintenance information, test procedures, test equipment
Report, “Guidelines for Air Sampling and Analytical Method
requirements, detailed diagrams, parts list, and specifications.
Development and Evaluation.” Such calculations are not
6.1.9.3 Bias and Precision Determinations—The manufac-
required for this practice; rather, accuracy is to be represented
turer shall make available specific instructions for tests to
by individual values of bias and precision.
determine bias and precision of the instrument, and shall
7.1.2.1 Bias—Thistestistobeperformedinanenvironment
provide the results of the instrument performance evaluation.
with a temperature of 19 to 24°C (66 to 75°F) and a relative
6.1.9.4 Recalibration—The manufacturer shall recommend humidity of 40 to 60%. The excitation source shall have an
a periodic recalibration cycle, as necessary, to ensure continu- isotopic strength within 610% of the isotopic strength of a
E2120 − 10 (2016)
nominally “fresh” or new source. To perform the test, use a using a linear regression analysis. Also calculate and report
wooden box having an inside width of 24 cm (9 ⁄2 in.) and thecorrelationcoefficient.Prepareaplotofstandarddeviations
oftheaverageofeachofthetenmeasurementvaluesversusthe
inside length of 37 cm (14 ⁄2 in.) and a height of about 50 cm
concentrationsofthestandardfilms.Includetheseresultsinthe
(20 in.) constructed from 10 mm ( ⁄8 in.) plywood, or equiva-
report of this evaluation.
lent.Thetopoftheboxshallbeopen,andtheboxistobefilled
with at least 35 cm (14 in.) of polyfoam beadboard (without
NOTE 8—These results are not to be used as an indication of the
instrument’s accuracy. They are solely to characterize the repeatability of
foil facing). Center a 23–cm (9–in.) by 35 cm (14 in.) by
the readings.
2.5cm (1 in.) thick white pine board, which is clear of major
NOTE 9—Bias and precision, as determined by this practice, provide
imperfections such as knots, on the polyfoam in the box.
only estimates of the bias and precision that may be achieved in the field.
Center a CRM at <0.2x on the top of the white pine board.
Biasandprecisioninthefieldwilldependupontheinstrumentcalibration,
the form and composition of the substrate, and the structure of the paint
Place the instrument on the film, and perform a total of ten
film being analyzed.
measurements without moving the instrument. Each measure-
7.1.2.4 Linearity with Real-World Substrates—The slope,
mentistoconsistofatotalofnominally1minofmeasurement
standard d
...