vxEPA
             United States
             Environmental Protection
             Agency
             Environmental Monitoring
             and Support Laboratory
             PO Box 15027
             Las Vegas NV 89114
 EPA-600/4-78-033
 June 1978
             Research and Development
Environmental
Monitoring Series
600478033
             Radioactivity Standards
             Distribution Program
             1978-1979
  EP 680/4
  73-001a
  978-79

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                RESEARCH REPORTING SERIES

Research reports of the Office of Research and Development, U S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology.  Elimination of traditional grouping  was  consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:

      1   Environmental  Health Effects Research
      2  Environmental  Protection Technology
      3.  Ecological Research
      4  Environmental  Monitoring
      5  Socioeconomic Environmental Studies
      6.  Scientific and Technical Assessment Reports (STAR)
      7  Interagency Energy-Environment Research and Development
      8  "Special" Reports
      9  Miscellaneous Reports

This report  has  been assigned to the ENVIRONMENTAL MONITORING  series.
This series describes research conducted to develop new or improved methods
and instrumentation for the identification and quantification of environmental
pollutants at the lowest conceivably significant concentrations.  It also includes
studies to determine the ambient concentrations of pollutants in the environment
and/or the variance of pollutants as a function of time or meteorological factors.
 This document is available to the public through the National Technical Informa-
 tion Service, Springfield, Virginia 22161

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                                          EPA-600/4-78-033
                                          June 1978
RADIOACTIVITY STANDARDS  DISTRIBUTION PROGRAM

                    1978 - 1979
                         by

                  Lee H. Ziegler
Monitoring Systems Research and Development Division
   Environmental Monitoring and Support Laboratory
             Las Vegas, Nevada  89114
        U.S.  ENVIRONMENTAL PROTECTION AGENCY
         OFFICE OF RESEARCH AND DEVELOPMENT
   ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY
              LAS VEGAS, NEVADA  89114

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                                DISCLAIMER
     This report has been reviewed by the Environmental Monitoring and Support
Laboratory-Las Vegas, U.S. Environmental Protection Agency,  and approved for
publication.  Mention of trade names or commercial products  does not constitute
endorsement or recommendation for use.
                                       11

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                                  FOREWORD


     Protection of the environment requires effective regulatory actions which
are based on sound technical and scientific information.  This information must
include the quantitative description and linking of pollutant sources, trans-
port mechanisms, interactions, and resulting effects on man and his environment.
Because of the complexities involved, assessment of specific pollutants in the
environment requires a total systems approach which transcends the media of air,
water, and land.  Ihe Environmental Monitoring and Support Laboratory-Las Vegas
contributes to the formation and enhancement of a sound monitoring data base
for exposure assessment through programs designed to:

          •  develop and optimize systems and strategies for moni-
             toring pollutants and their impact on the environment

          •  demonstrate new monitoring systems and technologies by
             applying them to fulfill special monitoring needs of
             the Agency's operating programs.

     This report tells which calibrated radioactivity samples are available to
laboratories concerned with monitoring environmental levels of radioactivity.
The calibrated radioactivity samples are intended for use in calibrating instru-
mentation, for verification of analytical methodology,  and for quality control.
The correct use of these samples will assist laboratories in producing precise
and accurate data.  The data from these measurements are used for a wide variety
of purposes, including assessment of health affects, establishment of. standards
and guides, and enforcement activities.  The Quality Assurance Branch at the
U.S. Environmental Protection Agency's Environmental Monitoring and Support La-
boratory in Las Vegas encourages the development and implementation of quality
control procedures at all levels of sample collection,  analysis, data handling
and reporting of environmental radiation measurements and can provide further
assistance upon request.
                                       ' Morgan
                                  Director
               Environmental Monitoring and Support Laboratory
                                  Las Vegas
                                     111

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                                 CONTENTS

                                                                 Page

Foreword	iii

Program Objectives	    1

Preparation and Calibration of Samples 	    1

Availability of Calibrated Samples 	    4

Participation in Calibrated Sample Distribution Program  ....    7


Appendix A.    Calibration Certificate   	    8

Appendix B.    Net Pulse Height Spectrum of Sodium-22 Measured
               with 4-Inch by 4-Inch Nal (Tl)  Crystal	11

Radionuclide Request Forms

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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 assessment of health effects, establishment
of standards and guides, and for enforcement activities.  It is, therefore, im-
perative that the precision and accuracy of the data be assured in order that
policy decisions concerning environmental quality be based on valid and compa-
rable data.

     The quality assurance program of the U.S. Environmental Protection Agency
(EPA) is designed to encourage the development and implementation of quality
control procedures at all levels of sample collection, analysis, data handling,
and reporting.  Quality control responsibilities, in the radiation area, have
been assigned to the Quality Assurance Branch at the EPA's Environmental Moni-
toring and Support Laboratory in 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 development of in-
tralaboratory and ixiterlaboratory quality control procedures and thus ensure
that environmental radiation data are valid.  Providing accurately calibrated
samples assists laboratories in calibrating new instruments, implementing and
maintaining routine instrument calibration programs, evaluating analytical pro-
cedures, and developing and revising data processing programs.

     The following pages briefly describe standard preparation procedures, list
the radionuclides available, and indicate how a laboratory may request standards.

     If your laboratory does not currently make use of the services provided by
the Quality Assurance Branch at the EMSL-LV, it is encouraged to do so.
                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 Rayonne-
ments lonisants  (France), Amersham Corporation, or from other reliable commer-
cial sources.  The uncertainty in the known activity of individual sources
ranges from 0.5 to 5 percent.  The activity of radionuclide impurities, exclud-
ing daughters, is documented and typically is less than 1 percent of the acti-
vity of the principal radionuclide at the time of sample preparation.

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     Upon receipt, a radionuclide is checked for its activity and for the pre-
sence of radioactive contaminants.  Hie sample is then diluted to the desired
activity level  (500-6,600,000 disintegrations per minute per gram (dpm/g))
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 aliquots of the solution
are flame-sealed in 5-milliliter glass ampuls.

     Accompanying each calibrated sample is a certificate listing pertinent
information concerning the sample and its calibration, including an estimate
of the errors associated with the value of the activity (Appendix A) .  For
gamma emitters, a plot of the net pulse height spectrum is also included  (Ap-
pendix B).

     To further assure the precision and accuracy of the calibrated samples,
the Quality Assurance Branch participates in an ongoing intercomparison study
with the National Bureau of Standards (NBS).  Definitions of traceability to
the national radioactivity measurement system is spelled out in an article
written by Cavallo et al.  (K. Siegbahn, ed., Nuclear Instruments and Methods,
Vol 112.  No. 1, 2.  Sept./Oct. 1973.  p. 5).  In this article it is stated:

         "Direct traceability to the national radioactivity measurement
          system  (NRMS) exists when any  "outside" laboratory prepares a
          batch of calibrated radioactivity standards and submits several
          randomly selected samples to the national standardizing labora-
          tory for confirmation and verification... Indirect traceability
          to the NPMS exists when the national laboratory provides  'un-
          known" calibrated radioactivity samples to one or more measure-
          ment laboratories, who in turn make measurements of activity
          that agree within certain specified limits with those of the
          national laboratory.  Thus we can have 1%, 5%, etc., trace-
          ability... Indirect traceability only means that the 'lower
          level" laboratory has the potential to make measurements that
          are consistent within the NEMS..."

     Table 1 is a listing of the results of the EPA's traceability program
with the NBS.  Shown in each category of direct or indirect traceability is
a nuclide and the ratio of the activity measured by EPA to the activity mea-
sured by the NBS.  In the section on direct traceability, each nuclide repre-
sents aliquots of seperate master solutions sent to the NBS at various times.
On the category of indirect traceability, the ratio of the activity measured
by EPA to the activity measured by the NBS is shown for different radionucli-
des.  More complete details of the intercomparison studies with the NBS are
described elsewhere.*
   Quality Assurance Branch, Radiation Quality Assurance Interccmparison Stu-
   dies  1974-1975, Environmental Monitoring and Support Laboratory, EPA-600/4-
   75-014, October 1975, Las Vegas, Nevada.

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      TABLE 1.  RATIOS OF ACTIVITY MEASUREMENTS PERFORMED UNDER THE EPA
          TRACEABILITY PROGRAM WITH NBS,  JANUARY 1974  TO MARCH 1978
                                                       EPA Value (Activity/g)

Direct traceability:

Samples submitted to NBS by
MSQ-EMSL-LV





Nuclide
60Co
51*Mn
65Zn
89Sr
90Sr
3H
1 3 lj
89Sr
89Sr
NBS Value
1.006
0.997
0.994
0.989
1.024
0.995
1.003
0.956
0.977
(Activity/g)









Indirect traceability:

     NBS-prepared samples sent to
     MSQ-EMSL-LV
                                        109
   Cd
 75
   Se
 89
 90
203
 51
137
                                           Sr
                                           Sr
                                           Hg
                                           Cr
                                           Cs
13 "
 59
 50
 59
 63
228
 45
llt7
152
239
                                           Cs
                                           Fe
                                           Co
                                           Mo
                                           Ni
                                           Th
                                           Ca
                                           Am
                                           Pm
                                           Eu
                                           Pu
                                        203
                                           Hg
0.970
1.028 (total activity)
0.919
0.951 (total activity)
0.997
1.008
1.024
1.015
0.981
1.018
1.013
0.996
1.001
0.958
0.989
0.970
1.049
0.995
1.008
0.959
0.986
0.979
1.004
1.017

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                   AVAILABILITY OF  CALIBRATED SAMPLES


      The Quality Assurance Branch recotmends use of  the half-lives listed in
 this document.  The primary sources of these half-lives are  "Nuclear Decay Data
 for Radionuclides Occurring in Routine Releases  from Nuclear Fuel Cycle Facili-
 ties", edited by D. C.  Kocher (ORNL/NUREG/TM-102,  UC-41, Oak Ridge National La-
 boratory, "Nuclear Decay Data for Selected Radionuclides", edited by M. J.
 Martin (ORNL-5114, VC - 34c - Nuclear Physics, Oak Ridge National Laboratory)
 and Nuclear Data Tables, Volume A8, Numbers 1, 2,  edited by  Katherine Way.
 Half-lives of those radionuclides not listed in  any  of  these publications were
 taken from selected volumes of the Nuclear Data  Sheets, edited by the Nuclear
 Data Group.
 AQUEOUS CALIBRATED SAMPLES

     The inventory of calibrated samples  at the beginning  of Fiscal Year  1978
consists of some 30 calibrated radionuclide solutions  (table 2).  Every effort
is made to keep this inventory supplied for immediate  delivery with the except-
ion of iodine-131 and barium-140.   Iodine-131 is prepared  bimonthly and dis-
tributed to requestors of record.   Barium-140 is prepared  approximately every
4 months and supplied to requestors of record.  While  the  types of calibrated
samples in the inventory vary during the  year,  every effort will be made  to
keep the following calibrated solution samples in  stock and available forv
distribution at any time.

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         TABLE  2.  CALIBRATED RADIONUCLIDE  SAMPLES KEPT IN INVENTORY
 Isotope
Type
Emission
3-
3-
3+,Y
3-,Y
Y
Y
3-,Y
3-
3+,Y
Y
3+,Y
3-
3-
3-,Y

Half-Life
12.35 y
5730 y
2.602 y
82.80 d
312.5 d
270.9 d
5.271 y
96 y
244.1 d
120 d
107 d
50.55 d
28.5 y
368.2 d

Isotope
109Cd
11 "%
125Sb
131J
133Ba
13 4Cs
137Cs
140Ba
14 "ce
226Ra
228Ra
238U
239pu
2ltlPu
241Am
Type
Emission
Y
3-,Y
3-,Y
3-,Y
Y
3-,Y
3-,Y
3-,Y
3-,Y
a,Y
3-
a
a
3-
a
Half -Life
453 d
250.8 d
2.77 y
8.04 d
10.5 y
2.062 y
30.17 y
12.789
284.3 d
1600 y
5.75 y
4.468 x 109 y
2.439 x 10" y
14.4 y
433 y
    3H
   22Na
   54Mn
   57Co
   60Co
   63Ni
   65Zn
   75Se
   90Sr

  106Ru
     Throughout the year, other radionuclide solutions are calibrated and made
available for distribution.  In order to service the user efficiently, the
Duality Assurance Branch will obtain, calibrate, and distribute the following
radionuclides, as time and resources permit, after 10 or more requests have
been received.  The user is reminded, however, that these solutions are pre-
pared as time permits, and as the Branch is able to maintain the above in-
ventory.
otope
7Be
51Cr
56Co
58CO
59Fe
85Sr
95Zr
o'Ru-1
Type
Emission
Y
Y
3+,Y
3+,Y
3-,Y
Y
3-,Y
03inRh 3-,Y
Half -Life
53.3 d
27.704 d
77.3 d
70.8 d
44.6 d
64.85 d
63.98 d
39.35 d
Isotope
121+Sb
139Ce
'"Ce
203Hg
230Th
232^


Type
Emission
3-,Y
Y
6-fY
3-,Y
a
a


Half-Life
60.20 d
137.65 d
32.50 d
46.59 d
7.7 x 10" y
1.405 x 1010 y



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     On occasion,  a few selected radionuclide solutions not listed in table 2
 are  calibrated.  letters will be sent to krown requesters of low-level radio-
 nuclide solutions  to efficiently allocate  the distribution of these solutions.


SOIL SAMPLES

     Several soil samples have been prepared and analyzed under contract for
distribution by EPA.  These soil samples have been dried, ground to pass a
170-mesh or a 200-mesh screen, and carefully blended.  Reports of calibration
accompany the samples.  The samples are packaged in glass containers which con-
tain roughly 10 grains (g) of soil.  Soils available are:

     1.   Standard Pitchblende

               Principal radionuclides      -   238U, 235U

               Principal daughter products  -   210Pb, 210Po,  23l*U, 230Th,

                                                231Pa, 226Ra,  227Ac,  227Th,
                                                21ltPb

     2.   Diluted Pitchblende

               This is approximately a 10:1 dilution of material 1
               with low-activity soil used for dilution.
     3.   Standard Monazite Ore

                                                   232,^  230mv,  228

                                                      3Ra
Principal radionuclides analyzed -  232Th, 230Th, 228Th,
                                    228T
     4.   Diluted Monazite Ore

               This is approximately a 10:1 dilution of material 3
               with low-activity soil used for dilution.

     5.   Uranium Mill Tailings  (1)

               Principal radionuclides analyzed -  230Th,  226Ra, 210Pb

     6.   Uranium Mill Tailings  (2)

               A composite mixture from 16 different uranium mills

               Principal radionuclides analyzed—  230Th,  226Ra, 210Pb

     7.   Diluted Uranium Mill Tailings

               A 7:1 dilution of material 6 with low-activity soil
               used for dilution.

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     The two following soil samples were prepared for the EPA by the NBS.
Material Number 8 is unspiked.  Supplemental information concerning the tech-
niques used to characterize the radium-226 and radium-228 concentrations is
supplied with the report of calibration prepared by the NBS.   The gamma-ray
emission rate standard is suitable for calibrating Nal(Tl)  and Ge(Li) detec-
tors for soil samples.

     8.   Mancos Shale

               This sample is certified for 226Ra and 228Ra activity.
               This sample is packaged in a glass jar containing ap-
               proximately 100 g of soil.

     9.   Pottery Clay - Gamma-Ray Emission Rate Standard

               This sample is spiked with 139Ce, 113Sn-113inIn,
               137Cs-13^^a,65Zn, and 88 Y.  This sample contains
               approximately 100 g of clay.


      PARTICIPATION  IN CALIBRATED  SAMPLES 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 at the back of this publication and return it to:

               U.S. Environmental Protection Agency
               Environmental Monitoring and Support Laboratory
               Quality Assurance Branch (MSQ)
               P.O. Box 15027
               Las Vegas, NV  89114
               Telephone:  (702) 736-2969

     All requests for calibrated samples should be submitted  at least 3 weeks
in advance in order to ensure delivery on the date required.   Should additional
forms be required, they may be requested from the same address.

     These materials are currently available cost-free to requesters.

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U.S. ENVIRONMENTAL PROTECTION AGENCY
ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY-LAS VEGAS
QUALITY ASSURANCE BRANCH
Calibration Certificate


Description Principal radionuclide 1 1 Half-life 1 1

Nominal activity 1 1 1 curies

Nominal volume 1 1 ml m ampoule/bottle number 1

Supplied to Request

D


I 1

Measurement Activity of principal radionuclide
Activity per gram of this solution
| || curies |o,|

at 0400 hours PST on I

Activity of daughter radionuclide
The principal activity was accompanied at the quoted time by
| | | curies | per gram

of thedaughter nuclide 1 J






Total mass of this solution Total principal activity per gram
at the quoted time
| grams | | | |

curies 1



Appendix A. Calibration certificate

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   Method of measurement
Useful Life This radionuchde has decayed through 1 1 half-lives since it was obtained by EMSL-LV
We recommend that this solution should not be used after
Purity The manufacturer states that activities other than that of the
and of it daughter nuclides if any, were estimated/known to
|m

| (2)

|,3,
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
I (1)

I (2)

| (3)

I I

principal nuclide
be
I less than 1 1 Qf (hg Clpa, actlvlty
equal to 1 1

II % 1 of the principal activity
edual to |__ —I

1 % 1 of the principal activity
equal to | | K

1 less than 1 1 1 curies/gram 1

1 less than 1 11 curies/gram 1

1 less than I II curies/gram 1

Appendix  A.  (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 principal activity had a standard error (a) not  greater than
                                   % I      (The 997% confidence limits are given by i 3a)
                    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 concentration of the principal activity has been estimated not  to
                    exceed    +          % (6)
                    The overall limits of error calculated on the basis of + (3cr + 6) or - (3o~* 6 ') are
                                 % I  or  I -         %  I   of the quoted radioactive concentration
                    The effective standard deviation is defined as 1/6th of the range between the overall limits

                    + (3
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io*   m
         345014     DPHDV 1 ?7ZD4DD
                                                          052174081
                         80           120
                          CHANNEL NUMBER
                                                               200
Appendix B-
Net pulse height  spectrum of sodium-22 measured
with 4-inch  x  4-inch Nal(Tl)  crystal
              •tf U.S. GOVERNMENT PRINTING OFFICE: 1978-765-924/1217 9-1
                                11

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                          RADIONUCLIDE REQUEST FORM
TO:       U.S. Environmental Protection Agency
          Environmental Monitoring and Support Laboratory
          Quality Assurance Branch
          P.O. Box 15027
          Las Vegas, NV  89114
Please ship the calibrated samples listed below to:

          Contact Person  	

          Title           	

          Laboratory      	

          Address
          Telephone

NRC License

  and/or

State License       Number(s)
NOTE:     If either by-products  (in quantities greater than exempt quanti-
          ties) or special nuclear materials are requested, a copy of the
          NRC 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 developing or check-
ing analytical procedures and/or for the calibration of instrumentation.

     I further certify that I am authorized to receive the above listed radio-
nuclides under the license number(s) listed above or that this laboratory is
exempt from licensing regulations.


Date 	   Signature 	

                              Title

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                          RADICNUCLIDE REQUEST FORM
TO:       U.S. Environmental Protection Agency
          Envirormental Monitoring and Support Laboratory
          Quality Assurance Branch
          P.O. Box 15027
          Las Vegas, NV  89114
Please ship the calibrated samples listed below to:

          Contact Person  	

          Title           	

          Laboratory      	

          Address
          Telephone
NRC License

  and/or            Type(s)
State License       Number(s)
NOTE:     If either by-products  (in quantities greater than exempt quanti-
          ties) or special nuclear materials are requested, a copy of the
          NRC license(s) should accotpany 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 developing or check-
ing analytical procedures and/or for the calibration of instrumentation.

     I further certify that I am authorized to receive the above listed radio-
nuclides 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
          Environmental Monitoring and Support Laboratory
          Quality Assurance Branch
          P.O. Box 15027
          Las Vegas, NV  89114
Please ship the calibrated samples listed below to:

          Contact Person  	

          Title           	

          Laboratory      	

          Address
          Telephone       	

NRC License
  ana/QT            Type(s)

State License       Number(s)
NOTE:     If either by-products  (in quantities greater than exempt quanti-
          ties) or special nuclear materials are requested, a copy of the
          NRC 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 developing or check-
ing analytical procedures and/or for the calibration of instrumentation.

     I further certify that I am authorized to receive the above listed radio-
nuclides 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-600/4-78-033
                             2.
                                                           3. RECIPIENT'S ACCESSION NO.
A. TITLE AND SUBTITLE

 RADIOACTIVITY STANDARDS DISTRIBUTION PROGRAM, 1978-1979
             5. REPORT DATE
                 June 1978
             6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
                                                           8. PERFORMING ORGANIZATION REPORT NO.
 Lee H. Ziegler, Quality Assurance Branch,
 Monitoring Systems Research and Development Division
9. PERFORMING ORGANIZATION NAME AND ADDRESS

 Environmental Monitoring and Support Laboratory
 Office of Research  and Development
 U.S. Environmental  Protection Agency
 Las Vegas. Nevada 89114	
             10. PROGRAM ELEMENT NO.

                 1HD621	
             11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
                                                            13. TYPE OF REPORT AND PERIOD COVERED
 U.S. Environmental Protection Agency - Las Vegas,  NV
 Office of Research and Development
 Environmental Monitoring and Support Laboratory
 Las Vegas. Nevada 89114	
             14. SPONSORING AGENCY CODE
                  EPA/600/07
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 descrip-
 tion of the preparation, availability, and distribution of calibrated radioactive sam-
 ples .  Instructions  and application forms are  included for laboratories desiring to
 participate in the program.

 This document is not a research report.  It is designed for use by personnel of labor-
 atories participating or desiring to participate in the Radioactivity Standards Dis-
 tribution Program, which is a part of the U.S. Environmental Protection Agency's qua-
 lity assurance program.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
                                              b.IDENTIFIERS/OPEN ENDED TERMS
                           c. COSATi F''ield/Group
 quality assurance
 quality control
 radioactivity
 quantitative analysis
 calibrating
 standards
                                 07  B
                                 14  B,  D
                                 18  H
18. DISTRIBUTION STATEMENT
 RELEASE TO PUBLIC
                                              19. SECURITY CLASS (This ReportJ

                                                UNCLASSIFIED
                           21 NO. OF PAGES
                                    28
20. SECURITY CLASS (This page J

 UNCLASSIFIED
                                                                         22. PRICE
EPA Form 2220-1 (Rev. 4—77)   PREVIOUS EDITION is OBSOLETE

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