EPA-680/4-75-002a
April 1975
RADIOACTIVITY STANDARDS DISTRIBUTION PROGRAM
1975
by
Quality Assurance Branch
Technical Support Laboratory
National Environmental Research Center
Las Vegas, Nevada
ROAP Number 22ADB
Program Element 1HA327
NATIONAL ENVIRONMENTAL RESEARCH CENTER
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
LAS VEGAS, NEVADA 89114
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PREFACE
Quality assurance is an integral part of any viable environmental
monitoring activity. The primary goals of the U.S. Environmental Pro-
tection Agency's (EPA) quality assurance program are to improve and
document the credibility of environmental measurements. To achieve
these goals, quality assurance is needed in nearly all segments of
monitoring activities and should cover personnel, methods selection,
equipment, and data handling procedures.
Five major functions, each essential to an effective quality
assurance effort, comprise EPA's quality assurance program.
• Promulgation of standardized methods of
measurement
• Distribution of standard reference materials
• Issuance of guidelines and procedures
• Training and technical assistance
• Evaluation and certification of monitoring
activities
This manual has been prepared to assist laboratories involved with
environmental radiation measurements in developing and maintaining a
quality control program and documenting the precision and accuracy of
their data. All EPA monitoring programs are requested to make use of
this document in planning their own radiation measurements and in
assisting the States in carrying out radiation monitoring activities.
Comments concerning the utility of this document, along with any
suggestions for possible changes and revisions, are welcomed. Questions
on matters related to quality assurance of environmental measurements
in various fields should be directed to the following person(s):
Air Pollution
Mr. Thomas Clark
Methods Standardization and Performance Evaluation Branch
Quality Assurance and Environmental Monitoring Laboratory
National Environmental Research Center
Research Triangle Park, North Carolina 27711
n
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Water
Mr. John Winter, Chief
Quality Assurance and Laboratory Evaluation Branch
Methods Development and Quality Assurance
Research Laboratory
National Environmental Research Center
Cincinnati, Ohio 45268
Pesticides
Mr. Jack Thompson, Chief
Chemistry Branch
Pesticides and Toxic Substances Effects Laboratory
National Environmental Research Center
Research Triangle Park, North Carolina 27711
Radiation
Mr. Arthur N. Jarvis, Chief
Quality Assurance Branch
Technical Support Laboratory
National Environmental Research Center
Las Vegas, Nevada 89114
Periodically, manuals and documents will be issued which provide
guidelines to be followed in all phases of monitoring activities. Use
of these guidelines throughout the Agency will enable a uniform approach
to be established within EPA which ultimately can be implemented at the
State level. This should permit a significant improvement in the
validity and reliability of environmental data collected throughout
the Nation,
The implementation of a total and meaningful national environmental
quality assurance effort cannot succeed without the full support of all
monitoring programs. Your cooperation is appreciated.
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CONTENTS
Page
Preface ii
Program Objectives 1
Preparation and Calibration of Samples ... 3
Availability of Calibrated Samples 8
Participation in Calibrated Sample
Distribution Program 10
Figures
1. Calibration Certificate 4
2. Net Pulse Height Spectrum of Sodium-22
Measured with 4-inch x 4-inch Nal(Tl)
Crystal 7
iv
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PROGRAM OBJECTIVES
Environmental measurements are made daily by many different
Federal, State, local and private agencies. The data from these
measurements are used for a wide variety of purposes including assess-
ment of health effects, the establishment of standards and guides, and
for enforcement activities. It is therefore imperative that the pre-
cision and accuracy of the data be assured in order that policy de-
cisions concerning environmental quality be based on valid and compar-
able data.
The quality assurance program of the U.S. Environmental Protection
Agency is designed to encourage the development and implementation of
quality control procedures at all levels of sample collection, analy-
sis, data handling, and reporting. Quality control responsibilities,
in the radiation area, have been assigned to the Quality Assurance
Branch at the EPA's National Environmental Research Center-Las Vegas.
This branch, as an integral part of its overall quality assurance
effort, prepares and distributes a variety of calibrated low-level
radioactive samples for use in the laboratories of Federal, State, and
local agencies.
The major objective of this program is to encourage the develop-
ment of intralaboratory and interlaboratory quality control procedures
and thus insure that environmental radiation data are valid. Providing
accurately calibrated samples assists laboratories in calibrating new
instruments, implementing and maintaining routine instrument calibra-
tion programs, evaluating analytical procedures, and developing and
revising data processing programs.
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The following pages briefly describe standard preparation pro-
cedures, list the radionucl ides available, and indicate how a labora-
tory may request standards.
If your laboratory does not currently make use of the services
provided by the Quality Assurance Branch at the NERC-LV, it is en-
couraged to do so.
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PREPARATION AND CALIBRATION OF SAMPLES
The radionuclides used in preparing calibrated samples are obtained
from the National Bureau of Standards, the Laboratorie de Metrologie des
Rayonnements lonisants (France), or from reliable commercial sources.
The uncertainty in the known activity of individual sources ranges from
0.5% to 5%. Activity of radionuclide impurities, excluding daughters,
is documented and typically is less than 1% of the activity of the
principal radionuclide.
Upon receipt, a radionuclide is checked for its activity and for
the presence of radioactive contaminants. The sample is then diluted
to the desired activity level (10,000-50,000 dpm/gm) with a carrier of
the same chemical composition and concentration as used by the supplier.
In certain cases the addition of a stabilizer is required. The accuracy
of the dilution is carefully checked and the solution flame sealed in
5-ml ampuls.
Accompanying each calibrated sample is a certificate (Figure 1)
listing pertinent information concerning the sample and its calibration
including an estimate of the errors associated with the value of the
activity. For gamma emitters, a net plot (Figure 2) of the pulse height
spectrum is also included.
To further assure the precision and accuracy of the calibrated
samples, the Quality Assurance Branch participates in on-going inter-
comparison studies with the National Bureau of Standards. These studies
involve the measurement of unknown samples supplied by the NBS, and the
measurement by NBS of EPA-prepared samples.
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U S ENVIRONMENTAL PROTECTION AGENCY
NATIONAL ENVIRONMENTAL RESEARCH CENTER-LAS VEGAS
QUALITY ASSURANCE BRANCH
Calibration Certificate
Description Principal radionuchde
Nominal activity
Nominal volume
ml in ampoule/bottle number
Supplied tc
Request
Measurement Activity of principal radionuclide
Activity per gram of this solution
at O4OO hours PST on
Activity of daughter radionuclide
The principal activity was accompanied at the quoted time by
curies per gra
of the daughter nuclide
TOTAL MASS OF THIS SOLUTION
TOTAL PRINCIPAL ACTIVITY PER
SRAM AT THE QUOTED TIME
Figure 1. Calibration Certificate
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Method of measurement
Useful Life
This radionuclide has decayed through half lives since it was obtained by NERC-LV
We recommend that this solution should not be used after
Purity
The manufacturer states that activities other than that of the principal nuelide
and of its daughter nuclides if any, were estimated/known to be
1 less than
I equal to
(1)
(2)
(3)
less than
equal to
less than
equal to
of the principal activity
°/o of the principal activity
% of the principal activity
The activity of impurity (1) is not (2) is not (3) is not included in the
quoted figures of the principal activity
It is estimated that we have added the following impurities
(D
(2)
(3)
cunes/gram
curies/gram
curies /gram
Figure 1 (continued). Calibration Certificate
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Random Errors
The repeatability of this standardization (dilutions, source preparations, counting statistics,
mass determinations, etc) was such that the certified value of the radioactive concentration
of the principle activity had a standard error (j) not greater than
(The 997% confidence limits are given by ± 3 o )
The total systematic error (sum of estimated maximum residual systematic errors due to
dispensing, counting losses counting corrections known uncertainty of standard) of the
certified radioactive concentrations of the principle activity has been estimated not to
exceed +
% (5)
The overall limits of error calculated on the basis of +(3 a + 5) or -(3 a + 6 ) are
% of the quoted radioactive concentration
The effective standard deviation is defined as 1/6th of the range between the overall limits
+(3 ff + 6 ) and -(3 a + 6') and is therefore
Decay Schemes This standardization is based on the following assumptions of the principle nuchde its
daughter nuclides and impurities (no allowance for error m these assumptions or the
assumption of quoted half-life have been included in the statement of accuracy above)
Chemical Carrier content per gram of solution
Composition
of Solution
Preservative
Other components
Remarks
Date Certificate Prepared
Approval Signature
Figure 1 (continued). Calibration Certificate
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103
NET
CPM
10
10
1,64
120
160
200
CHANNEL NUMBER
Figure 2. Net Pulse Height Spectrum of Sodium-22 Measured
with 4-inch x 4-inch Nal(Tl) Crystal
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AVAILABILITY OF CALIBRATED SAMPLES
The current inventory of calibrated samples consists of some forty
different radionucl ides. The table below lists the available radio-
nuclides along with a schedule of their delivery dates. Radionucl ides
scheduled for delivery during a particular month will be prepared once
during this year. They will be available after this month until the
inventory is depleted, or until their decay negates the calibration.
CALIBRATED SAMPLE DISTRIBUTION SCHEDULE
Isotope
3H
7 Be
22Na
51
Cr
56Co
57Co
5bCo
59Fe
60Co
65Zn
75Se
85Kr
85Sr
Type Emission Half-Li fe*
Delivery
B"
Y
B~
,Y
,Y
Y
Y
Y
Y
,Y
,Y
,Y
Y
,Y
Y
12.26 years
53.6 days
5730 years
2.62 years
83.9 days
27.8 days
303 days
77.3 days
270 days
71.3 days
45.6 days
5.26 years
245 days
120.4 days
10.8 years
64 days
Stock
Feb
Stock
Stock
Oct, Jan
Feb
Stock
May
Stock
Apr
Apr
Stock
Stock
Stock
May
Stock
* Lederer, C., et al., Table of Isotopes., sixth edition, John Wiley and
Sons, New York 1967
8
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CALIBRATED SAMPLE DISTRIBUTION SCHEDULE (continued)
Isotope
88y
Type Emission Half-Life*
90Sr
106Ru
1311
195AU
203Hg
232Tht
a >Y
108 days
52 days
27.7 years
65 days
39 days
368 days
453 days
255 days
60.4 days
2.71 years
8.06 days
7.2 years
2.04 years
30 years
140 days
12.8 days
32.5 days
284 days
183 days
46.9 days
1602 years
8 x 104 years
1.4 x 1010 years
4.5 x 109 years
2.4 x 10** years
433 years**
Delivery
Jan
Stock
Stock
Jun, Dec
Mar, Nov
Stock
Stock
Stock
Mar, Oct
Stock
Monthly
Stock
Stock
Stock
Feb
Within 4 months
Mar
Stock
Stock
Sep
Stock
Jul
Stock
Stock
Stock
Stock
* See footnote on page 8
** NBS Certificate Standard Reference Material
americium-241, April 1970
t Possible State license required
tt Byproducts license required
ttt Special nuclear material license required
4904-D. a-part standard
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PARTICIPATION IN CALIBRATED SAMPLE DISTRIBUTION PROGRAM
Any Federal, State, local or private laboratory involved in, or
concerned with, environmental radiation monitoring and surveillance
may participate in the calibrated sample distribution program. To
request samples, complete one of the request forms included in this
publication and return it to:
U.S. Environmental Protection Agency
National Environmental Research Center
.Quality Assurance Branch (TSQ)
P.O. Box 15027
Las Vegas, NV 89114
All requests for calibrated samples should be submitted at least three
weeks in advance in order to insure delivery on the date required.
Should additional forms be required, they may be requested from the
same address.
10
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RADIONUCLIDE REQUEST FORM
TO: U.S. Environmental Protection Agency
National Environmental Research Center
Quality Assurance Branch (TSQ)
P.O. Box 15027
Las Vegas, NV 89114
Please ship the calibrated samples listed below to:
Contact Person
Title ___
Laboratory
Address
Telephone
AEC License
and/or
State License Number(s)
NOTE: If either byproducts (in quantities greater than exempt quanti-
ties) or special nuclear materials are requested, a copy of the
AEC license(s) should accompany the first request.
Radionuclide Samples Desired:
I certify that the calibrated sample(s) requested are to be used
only in this laboratory by qualified personnel for the purpose of de-
veloping or checking analytical procedures and/or for the calibration
of instrumentation.
I further certify that I am authorized to receive the above listed
radionuclides under the license number(s) listed above or that this
laboratory is exempt from licensing regulations.
Date Signature
Title
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RADIONUCLIDE REQUEST FORM
TO: U.S. Environmental Protection Agency
National Environmental Research Center
Quality Assurance Branch (TSQ)
P.O. Box 15027
Las Vegas, NV 89114
Please ship the calibrated samples listed below to:
Contact Person
Title
Laboratory
Address
Telephone
AEC License
and/or
State License Number(s)
NOTE: If either byproducts (in quantities greater than exempt quanti-
ties) or special nuclear materials are requested, a copy of the
AEC license(s) should accompany the first request.
Radionuclide Samples Desired:
I certify that the calibrated sample(s) requested are to be used
only in this laboratory by qualified personnel for the purpose of de-
veloping or checking analytical procedures and/or for the calibration
of instrumentation.
I further certify that I am authorized to receive the above listed
radionuclides under the license number(s) listed above or that this
laboratory is exempt from licensing regulations.
Date Signature
Title
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORT NO
EPA-680/4-75-002a
3. RECIPIENT'S ACCESSION-NO.
4 TITLE AND SUBTITLE
Radioactive Standards Distribution Program — 1975
5. REPORT DATE
April 1975
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S)
Quality Assurance Branch
Technical Support Laboratory
8. PERFORMING ORGANIZATION REPORT NO.
9 PERFORMING ORG \N1ZATION NAME AND ADDRESS
National Environmental Research Center
U.S. Environmental Protection Agency
P. 0. Box 15027
Las Vegas, Nevada 89114
10. PROGRAM ELEMENT NO.
1HA327
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Interim 1975
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
A program for the distribution of calibrated radioactive samples, as one function
of EPA's quality assurance program for environmental radiation measurements, is
described. Included is a discussion of the objectives of the distribution program
and a description of the preparation, availability, and distribution of calibrated
radioactive samples. Instructions and application forms are included for labora-
tories desiring to participate in the program.
This document is not a research report. It is designed for use by personnel of
laboratories participating or desiring to participate in the Radioactivity Standards
Distribution Program which is a part of the U.S. Environmental Protection Agency's
quality assurance program.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
quality assurance
quality control
radioactivity
quantitative analysis
calibrating
standards
07 05/14 04
13. DISTRIBUTION STATEMENT
Release unlimited
NERC-LV, NTIS
19. SECURITY CLASS (This Report)
Unclassified
21. NO OF PAGES
17
20 SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
GPO G9J-413
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