ASTM D5072-09(2016)
(Test Method)Standard Test Method for Radon in Drinking Water
Standard Test Method for Radon in Drinking Water
SIGNIFICANCE AND USE
5.1 The most prevalent of the radon isotopes in ground water is 222Rn. This isotope presents the greatest health risk compared to the other naturally occurring radon isotopes if ingested via the water pathway.
SCOPE
1.1 This test method covers the measurement of radon in drinking water in concentrations above 2 Bq/L.
1.2 This test method may be used for absolute measurements by calibrating with a 226Ra standard or for relative measurements by comparing the measurements made with each other.
1.3 This test method is used successfully with drinking water samples and Type III reagent water conforming to Specification D1193. It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
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: D5072 − 09 (Reapproved 2016)
Standard Test Method for
Radon in Drinking Water
This standard is issued under the fixed designation D5072; 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 PB2004-105421, July 2004
1.1 This test method covers the measurement of radon in
3. Terminology
drinking water in concentrations above 2 Bq/L.
3.1 Definitions:
1.2 This test method may be used for absolute measure-
3.2 For definitions of terms used in this standard, refer first
ments by calibrating with a Ra standard or for relative
toTerminologyD7902andsecondtoTerminologyD1129.For
measurements by comparing the measurements made with
terms not defined in this standard, or in Terminologies D7902
each other.
or D1129, reference may be made to other published glossa-
1.3 This test method is used successfully with drinking
ries.
water samples and Type III reagent water conforming to
SpecificationD1193.Itistheuser’sresponsibilitytoensurethe
4. Summary of Test Method
validity of this test method for waters of untested matrices.
4.1 This test method is based on the scintillation counting
1.4 The values stated in SI units are to be regarded as
of Rn and its progeny.
standard. No other units of measurement are included in this
4.2 Inaglassliquidscintillationvial,analiquotofunaerated
standard.
water is drawn into a syringe then gently injected beneath 10
1.5 This standard does not purport to address all of the
mL of a suitable liquid scintillation cocktail that does not
safety concerns, if any, associated with its use. It is the
contain an emulsifier. The vials are capped, shaken, and
responsibility of the user of this standard to establish appro-
allowed to stand 3 hours prior to counting to permit dark
priate safety and health practices and determine the applica-
adaptation and buildup of short-lived radon progeny. Radon-
bility of regulatory limitations prior to use.
222 contained in the sample is selectively partitioned into the
scintillation cocktail. The sample is counted using a liquid
2. Referenced Documents
scintillation counting system optimized for detection of Rn
2.1 ASTM Standards:
activity.
D1129Terminology Relating to Water
D1193Specification for Reagent Water
5. Significance and Use
D2777Practice for Determination of Precision and Bias of
5.1 The most prevalent of the radon isotopes in ground
Applicable Test Methods of Committee D19 on Water
water is Rn. This isotope presents the greatest health risk
D3370Practices for Sampling Water from Closed Conduits
compared to the other naturally occurring radon isotopes if
D7902Terminology for Radiochemical Analyses
ingested via the water pathway.
D5847Practice for Writing Quality Control Specifications
for Standard Test Methods for Water Analysis
6. Interferences
2.2 Other Documents:
6.1 Other radionuclides soluble in the scintillation cocktail
Multi-Agency Radiological LaboratoryAnalytical Protocols
may interfere. High energy beta/gamma emitters, even though
Manual EPA402-B-04-001A, NUREG1576, NTIS
theyarenotsolubleinthescintillationmix,mayalsointerfere.
These interferences will cause a high bias if present in a
This test method is under the jurisdiction ofASTM Committee D19 on Water
significant quantity. These interferences would be rare in
andisthedirectresponsibilityofSubcommitteeD19.04onMethodsofRadiochemi-
drinking water samples but may be observed in some cases.
cal Analysis.
Current edition approved Feb. 1, 2016. Published February 2016. Originally
6.2 Areduced or increased counting efficiency may result if
ɛ1
approved in 1992. Last previous edition approved in 2009 as D5072–09 . DOI:
sample quenching is significantly different than that of the
10.1520/D5072-09R16.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or calibration standard.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
6.3 Scintillation stock cocktails and sample cocktail mixes
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. must be dark-adapted to prevent artificial excitation of fluors
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5072 − 09 (2016)
which may lead to falsely elevated count rates which could 10. Sampling
NOTE1—RefertoPracticesD3370forapplicablesamplinginstructions.
compromise data quality.
Also see U.S. Environmental Protection Agency reports EPA 520 and
EPA 600.
7. Apparatus
10.1 Attach the sampling funnel and tube to a faucet with
7.1 Sampling Funnel.
the standard faucet fitting.
7.2 Tube, with standard faucet fitting.
10.2 Slowly turn on the water and allow a steady stream to
7.3 Disposable Syringe, 12 mL capacity, with 20 gauge, 38
flowoutofthefunnelforapproximately2min.Thispurgesthe
mm hypodermic needle.
tube and ensures a fresh sample.
7.4 Glass Liquid Scintillation Vials, 20 mL capacity with
10.3 Reduce the flow of water and invert the funnel. The
polyethylene inner seal cap liners.
flow should be adjusted to a level that does not cause
turbulence in the pool of water contained in the funnel.Allow
7.5 Liquid Scintillation Counter.
excess water to spill over one edge of the funnel.
8. Reagents and Materials
10.4 Examine the hose connection and tubing for air
8.1 Purity of Reagents—Reagent grade chemicals shall be bubbles or pockets. If these are visible, raise or lower the
funnel until they are removed.
used in all tests. Unless otherwise indicated, it is intended that
all reagents shall conform to the specifications of the Commit-
11. Calibration and Standardization
tee onAnalytical Reagents of theAmerican Chemical Society,
3 226
where such specifications are available. Other grades may be 11.1 Add a known quantity of traceable Ra standard
used, provided it is first ascertained that the reagent is of solution to a known volume of water.
sufficiently high purity to permit its use without lessening the 222
11.2 Preparethree Rncalibrationstandardsbycombining
accuracy of the determination. 226
a 10 mL aliquot of the Ra standard solution with 10 mL of
8.2 Purity of Water—Unless otherwise indicated, references scintillation cocktail in a 20 mL glass scintillation vial.
to water shall be understood to mean conforming to Specifi- Securely cap each vial and shake to mix the contents.
cation D1193, Type III.
11.3 In liquid scintillation vials, prepare three background
8.3 Radioactive Purity of Reagents—Radioactive purity samplescontaining10mLofTypeIIIreagentwaterand10mL
shall be such that the measured radioactivity of blank samples of scintillation solution. Cap the vials and shake to mix the
doesnotexceedthecalculatedprobableerrorofmeasurements. contents.
8.4 Radium-226 Solution Standard, traceable to a national 11.4 Allowapproximately30daysforbuildupofradon(that
standardslaboratorysuchastheNationalInstituteofStandards is, secular equilibrium with Ra).
and Technology (NIST) or the National Physical Laboratory
11.5 Shake vial to transfer nearly all the radon to the
(NPL).
scintillation mix phase (radon is highly soluble in the scintil-
8.5 Scintillation Cocktail Mix, without emulsifier. Toluene lation mix). The Ra remains in the aqueous phase and,
based mix is acceptable. therefore, does not contribute significantly to the count rate.
11.6 Allowforthebuildupofshort-livedradonprogenyand
9. Safety
for dark-adapting by waiting 3 hours before counting.
9.1 Somescintillationcocktailscanposeasignificanthealth
11.7 Count the standard samples for a counting period
hazard if handled improperly. Refer to manufacturer instruc-
sufficientlylongtoobtainarelativecountinguncertaintyof<1
tions for the safe use of these materials.
%(10000netcountsminimum).Countbackgroundsamplesat
least as long as the test samples.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For Suggestions on the testing of reagents not EPA520/5–83–027MethodsandResultsofEPA’sStudyofRadoninDrinking
listed by the American Chemical Society, see Annual Standards for Laboratory Water. Published December 1983.Available from U.S. Government Printing Office
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE,
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, Washington, DC 20401, http://www.access.gpo.gov.
MD. EPA 600/2–87/082 Two Test Procedures for Radon in Drinking Water.
If this water is not aerated or degassified prior/subsequent to demineralization, Published March 1989. Available from U.S. Government Printing Office Superin-
radon background may be substantial. This can happen if the lab uses RO, EDI or tendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC
only deminerialization resins for purification of their water. 20401, http://www.access.gpo.gov.
D5072 − 09 (2016)
11.8 Calculate the calibration factor (CF) as in accordance 13.2 SampleActivity,AC—Calculate the radon activity con-
with 13.1. centrationinthesampleasfollows.Firstcalculatethenetcount
rate in counts per second:
12. Procedure
R 5 R 2 R (2)
n a b
Then calculate the activity concentration of radon in the
12.1 Cleanscintillationvialswithalcoholandadd10mLof
sample, in becquerels per litre (Bq/L), using the following
scintillation cocktail.
equation:
12.2 Collect unaerated sample in accordance with Section
R
n
10.
AC 5 (3)
CF 3D 3V
a
12.3 Placethetipofthehypodermicneedleapproximately3
where:
cm under the surface of the water in the funnel and withdraw
AC = activity concentration of Rn (Bq/L),
a few millilitres of water and eject this water. Using this
−1
R = Sample count rate (s ),
a
procedure, rinse the syringe and hypodermic needle two or
−1
R = background count rate (s ),
b
three more times.
−1
R = net count rate (s ),
n
12.4 Again, place the tip of the needle approximately 3 cm CF = calibration factor calculated as in Eq 1,
–ln(2) × T/t
½
D = decay correction factorD=e ,
belowthesurfaceofthewaterandwithdrawapproximately12
V = volume of sample analyzed (0.010 L),
mL.
a
T = time in days from collection time to midpoint of
NOTE 2—The water should be pulled into the syringe slowly to avoid
counting time, and
extreme turbulence and collection of air bubbles. If large air bubbles are
t = half-life of Rn, 3.82 d.
½
noticed in the syringe, the sample should be rejected and redrawn.
13.3 EstimatethesquareofthestandarduncertaintyofR as
n
12.5 Invert the syringe and slowly eject any small air
follows:
bubblesandextrawater.Retainprecisely10mLofwaterinthe
syringe.
J 3R 12R
n b
, ifR .0
n
t
12.6 Remove the cap from a vial and carefully place the tip 2
u R 5 (4)
~ !
n
R 1R
a b
oftheneedleintothebottomoftheliquidscintillationsolution. 5
, ifR #0
n
t
Slowly eject the water from the syringe into the vial.
where:
NOTE 3—Water is injected under the liquid scintillation solution to
prevent loss of radon from the sample. If the water is forced out of the t = counting time of the sample and background (s), and
syringe with much pressure, it will cause turbulence in the solution and
J = index of dispersion for the net counts produced by Rn
could result in loss of radon.
and its progeny.
12.7 Carefully withdraw the hypodermic needle from the
Ifthecountingtimetis3000s,thenJisapproximatelyequal
vial and replace the cap. The cap should be tightly secured to
to 1.83 if the counter is configured to count alpha radiation
prevent leakage. Shake the vial to mix the contents.
only and J is approximately equal to 2.78 if it is configured to
count both alpha and beta radiation. For longer count times
12.8 Repeat the previous steps to obtain two separate
estimate J as follows:
aliquots from each sample.
12.9 Load the samples into the liquid-scintillation counting
2λ t
i
c 1 c e
5 i
(
i50
system and after waiting for 3 h, count at least 50 minutes.
J 5 (5)
2λ t
1 2 e
12.10 After dark-adapting them, count a background
where the decay constants λ through λ are given by:
sample,consistingof10mLofwaterand10mLofscintillation
0 3
−6 −1
solution,andastandardradium-226solutionsamplefor50min λ = 2.098 × 10 s ,
−1
atthebeginningofcountingandaftereverytendrinkingwater λ = 0.003 727 s ,
−1
λ = 0.000 431 s , and
samples.
−1
λ = 0.000 581 s .
13. Calculation
and where the coefficients c through c are given either by:
0 5
13.1 Calibration Factor, CF:
c = −3.0060503
c = 0.00038339968
~C 2 C !
CS B
CF 5 (1) c = 0.026908241
A
CS
c = −0.015190995
where: c =0
c = 2.9939497
C = calibration standard count rate, counts per second
CS
−1
(s ) (as prepared in 11.2),
−1
C = average background sample count rate (s ) (as pre-
B
pared in 11.3), and
226 Lucas, H.F., Jr., and D.A. Woodward, Journal of Applied Physics, Vol. 35, pg.
A = calibration standard Ra activity, Bq.
CS
452, 1964.
D5072 − 09 (2016)
FIG. 1 Plot of J Verses Count Time (minutes) from Eq 5
ifthecounterisconfiguredtocountalpharadiationonly,orby:
R
b
2.33
Œ
c = −5.0106487
t
L 5 (8)
c
c = 0.00020574781
1 CF 3D 3V
a
c = 0.036387727
where:
c = −0.015296013
c =0 L = critical level radon activity concentration (Bq/L).
4 c
c = 4.9893513
14. Precision and Bias
if the counter is configured to count both alpha and beta
14.1 The collaborative test conducted on this test method
radiation.
included 15 laboratories each with one operator.Three activity
13.4 The combined standard uncertainty of the radon activ-
levels between 60 Bq/Land 2454 Bq/Lwere tested with three
ity concentration can be estimated as follows:
replicatesperlevel.Thedeterminationoftheprecisionandbias
2 2 2 2 2
=u R 1R 3 u CF 1u V 1u D statements were made in accordance with Practice D2777.
~ ! ~ ~ ! ~ ! ~ !!
n n r r a r
u ~AC! 5 (6)
c
CF 3D 3V
a
14.2 These collaborative test data were obtained using
reagent grade water. For other matrices, these data may not
where:
apply.
u (AC) = combined standard uncertainty of the radon activ-
c
ity concentration (Bq/L), 14.3 The overall and single operator precision have been
u (CF) = relative standard uncertainty of the calibration found to vary with level in a manner according to Table 1.
r
factor CF,
14.4 The bias of this test method, based upon the collab-
V = volume of sample analyzed (0.010 L),
a
ora
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.