United States
                 Environmental Protection
                 Agency
              Office of
              Radiation Programs
              Washington. D.C. 30460
EPA-520/1 -87-003-34
January 1987
                 Radiation
vvEPA
Radon/Radon  Progeny
Measurement  Proficiency
Program
Proficiency Report: North Carolina
                 (This publication valid through July 1987)

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            PROFICIENCY REPORT

(This  publication valid through July 1987)
             EPA Test Round 3
     ;           Prepared by

    Radon Technical  Information Service
        Research Triangle Institute
              (919)  541-7131
               Prepared for

       Office of Radiation Programs
   U.S.  Environmental Protection Agency
          Washington, D.C.  20460
               January 1987

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                           TABLE OF CONTENTS
Introduction	    1
Selection of Measurement Method	    3
Program Requirements	*.	    8
Explanation of Acronyms	    8
Table 1:  Measurement Companies Serving Your State	    9

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                             INTRODUCTION

     Recent  public  concern over  the health  effects from  exposure to
radon has greatly increased the demand for companies qualified to meas-
ure radon and radon progeny in  indoor  air.   In response to States' re-
quests for  assistance,  the U.S. Environmental  Protection  Agency's Of-
fice of Radiation Programs  has  developed the Radon/Radon Progeny Meas-
urement Proficiency (RMP) Program.  Under this  program,  any company of-
fering measurement services —  directly,  or  indirectly through another
company — is invited to demonstrate its proficiency in measuring radon
gas and/or radon progeny levels.
     The program's immediate objective is to assist  States and the pub-
lic  in  selecting  companies  that  have  demonstrated  competence  in
measuring  indoor radon  and/or radon  progeny.    This  is  achieved  by
evaluating, on a semiannual basis, the proficiency of companies' detec-
tor operations, and the quality of their data management.  Those compa-
nies that demonstrate proficiency  in each  of these areas are listed in
the Proficiency Report.  The program's long-term objectives are to pro-
mote standard measurement procedures among measurement companies and to
establish quality assurance procedures for all  measurement companies.
     The RMP  Program  is not designed for  accrediting  measurement com-
panies.  Nor  does  it  certify,  recommend, or  endorse participating com-
panies.  The  inclusion of a company in this report should not be inter-
preted as a  certification  or  accreditation of  that  company.   This re-
port is only a source of measurement  companies that have demonstrated
capabilities for measuring radon and radon progeny levels.
     The testing periods, are referred  to as  test "rounds".   Each round
consists of  two  tests -- a performance  test  and a  follow-up  test.   A
company  enrolls  its  measurement  methods   (e.g.,   activated  charcoal
adsorption) for evaluation.  EPA tells the company to submit a specific
number and type of detectors (e.g., charcoal canisters) for exposure to
known  levels of  radon  and/or radon  progeny.   After exposure,  EPA
returns  the  detectors  to  the  company.    The  company analyzes  the
detectors and reports its measurement results to EPA.  EPA compares the
companies measurement  results  with the  known   levels of  exposure.   If

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the company's  results  are  within  the established screening-measurement
criteria, the  method  passes  the performance test.   If not, the method
is automatically tested again in the follow-up test.   The  same detector
submittal and  exposure  procedures  are  followed  for  the follow-up test.
A company must  take  part  in  the follow-up test  if  it  fails any of  the
program  requirements   in   the   performance  test,   not   simply   the
screening-measurement  criteria.   Companies  that  fail  again   in   the
follow-up test  may participate  in  the  next test  round.  Only companies
having met  all  the  program requirements for a method(s)  in either  the
performance  or the  follow-up  test  for  a  round  are  listed  in  this
report.
     Table  1  lists  all the  proficient companies  offering measurement
services in your  State.  Numerous companies distribute mail-in detec-
tors and make measurements nationwide.  Therefore, the  companies offer-
ing nationwide  service  are listed first under  "National"  heading,  and
those serving your State only are  listed next.

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                    SELECTION OF MEASUREMENT METHOD

     Several different measurement methods may be used to determine the
radon  or  radon  progeny concentrations  in  houses.   In  practice,  the
choice of  a method is often  dictated  simply by  availability  — if  an
adequate method  is  available, you use  it.   If  alternative methods are
available,  then  the cost or  the duration of the measurement may become
the deciding factor.
     EPA has developed  measurement  protocols for seven different meth-
ods,  and  believes that any of  them,  when used  in  accordance  with EPA
protocols,  can  produce  valid results.   This does  not mean  that all
measurements  made according  to  the  suggested   protocols  will  produce
results with  identical  uncertainties.   However,  it  does mean that the
listed methods  are  capable of producing adequate results for  screening
or follow-up purposes.
     Each  method has  its own  advantages and disadvantages.  Users  must
decide which method  is  best  suited  to their situations.  The  following
sections  describe the  characteristics  of the  seven methods,  pointing
out some of the  advantages and  disadvantages  of  each one.   This  summary
is  not exhaustive,  but is   intended  to guide  the  user  in  making  an
informed  selection of a measurement  method.

Continuous Radon Monitoring  (CR)  and  Continuous  Working-Level
Monitoring (CW)
      These measurement methods  are  similar in  that they use  an  elec-
tronic detector  to  accumulate and store  information related to  the pe-
riodic  (usually  hourly)  average concentration  of   radon  gas  or  radon
progeny.   They  are installed  in  houses according to guidelines  in the
EPA protocol,  and then turned on or programmed  for  the  desired  operat-
ing time  — a  minimum of  six hours for  screening and  twenty-four  hours
for follow-up  measurements.   At  the  end of the test, the  monitor  must
be  retrieved,  and the results must be  analyzed  by a skilled  instrument
operator.

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     Advantages
     o   Relatively short measurement duration.
     o   Hourly results can track the .variation  of concentrations in the
        house.
     o   Very precise (most models).
     o   Results  are available on-site (for CW).
     Disadvantages
     o   Relatively expensive, cost may range from $100 to $300, depend-
        ing on the type of services provided.
     o   Requires a skilled instrument operator.
     o   This, as does any short-term measurement, requires careful con-
        trol of closed-house conditions  twelve hours  before and during
        the test.

Alpha-Track Detection (AT)
     The alpha-track method measures  radon.  An AT detector is a  small
sheet  of  special  plastic  material enclosed  in a  filtered container.
The container collects  the radon  progeny on the filter paper while the
radon  gas enters the container.  As the  gas  and  some of the short-lived
progeny  decay,  they  emit alpha  particles  that permanently  mark the
plastic sheet.
     The detectors  are  installed  in the  home according to guidelines  in
the EPA protocol.   They  are  left  for  periods of up to three months for
screening and twelve  months  for follow-up measurements.   At the end  of
the desired testing period, they must be  returned to the distributor  or
analytical  laboratory for processing  and  evaluation.
     Advantages
     o  Relatively  low-cost services; cost  may range from $20 to $60.
     o  No  special  skills required  for making  the measurement.
     o  Can be distributed by mail.
     o  Completely  passive, needs  no  external  power.
     o  Can measure the  long-term  average concentrations over  a twelve-
        month period, which  is  the  optimal  measure  of  long-term concen-
        trations.
     Disadvantages
     o  Relatively  long measurement  period  necessary;  three months  is
        the recommended  minimum for currently  available detectors.

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Activated Charcoal Adsorption (CC)
     The charcoal  adsorption  method  measures  radon gas.  The detectors
for this method  consist of variously configured containers filled with
a measured  amount  of activated charcoal.   The  container is often per-
forated or  screened  to  keep the charcoal from falling  out  and to  filter
out radon progeny.   All charcoal  adsorbers are stored  in  airtight con-
tainers when not being  used for sampling.
     Charcoal adsorbers can be received  through the mail from a distri-
butor.  They are  installed  in the home for up to  seven  days, according
to guidelines in the EPA protocols.  At  the end of testing, an adsorber
is  resealed and returned  to  the distributor or   analytical  laboratory
for processing  and evaluation.
     Advantages
     o  Low cost for services; costs may range from $10 to  $25.
     o  Can be  distributed by mail.
     o  No  special skills needed  for making the measurement.
     o  Completely passive, needs no external power.
     o  With proper  analysis, can yield  precise results.
     Disadvantages
     o  Some charcoal  adsorbers  are  more sensitive than others to tem-
        perature  and humidity.
     o  Limited to short-term testing.
     o  Requires,  as does any  short-term  measurement,  careful control
        of  closed-house conditions twelve  hours  before and during  the
        test.

Radon Progeny  Integrating  Sampling Unit-RPISU (RP)
     The  RP method  measures  radon progeny.  RP detectors  have a flow-
rate  air  pump  that  pulls air continuously  through a  detector  assembly.
Depending on the  model, the  unit  can be installed  and operated  by home-
owners  or  skilled  operators for three days  or  longer   according  to
guidelines  in  the EPA  protocol.   At  the end of  that  time,  the homeowner
sends  it  to the  distributor,  or   an  operator  removes  the  unit  and
returns  it  to  the analysis  laboratory for  processing  and evaluation.

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     Advantages
     o  Directly measures concentrations of radon decay products.
     o  Relatively short measurement period.
     o  The detector  assembly and  some entire  units can  be sent  by
        mail.
     o  There  is extensive experience in the use of RPISU's; therefore,
        measurement errors are well established.
     Disadvantages
     o  Relatively expensive; cost  may  range  from  $40 to $150,  depend-
        ing on type of service provided.
     o  Some models may be both heavy and awkward to move.
     o  May be limited to locations with AC power.
     o  Some units must be installed and picked up by a skilled  instru-
        ment operator.
     o  Because of the  highly  reactive  nature of radon decay products,
        measurements  are  much  more susceptible to  sampling error than
        radon  gas measurements.

Grab Sampling   (Gw) - Radon (GR) and Radon Progeny  (GW)

     The grab  sampling  methods measure concentrations of  radon  gas or
radon progeny  concentrations.  The  radon  grab sample is collected in  a
special flask  holding 100 to 2,000  cubic centimeters  of  air.  The radon
progeny grab sample  is  collected  by drawing  air through a  filter, upon
which progeny,  if  present  in  the  air,  are collected.  Both samples can
be  acquired simultaneously with  some  detector systems.   All sampling
should be done  in  accordance to guidelines in  the  EPA protocol.
     For results of the grab radon  test, operators must  return to their
offices to  analyze the exposed detectors, and must delay  the analysis
for  at least four  hours after  the testing.  For most  grab working-level
tests  (radon  progeny),  operators can perform the  analysis on location
in  an hour or  less.
     Advantages
     o  Results  are quickly obtained.
     o  Equipment  can be  portable.
     o  Some  detector systems can  sample  both  radon and radon  progeny
        simultaneously.
     o  Can acquire and evaluate  several samples per day.

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o  Conditions during the measurement are known to the operator.
Disadvantages
o  Relatively expensive; costs may range from $80 to $300, depend-
   ing on the type of services offered.
o  Very short measurement periods may not be representative of the
   long-term average concentrations.
o  Requires a skilled operator.
o  Requires, as does with any short-term measurement, careful con-
   trol of  closed-house  conditions  twelve  hours  before  and during
   the test.

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                         PROGRAM REQUIREMENTS

     For each method, participants must  send  with  their applications a
copy of the operating instructions that they provide to homeowners and/
or are used by an instrument operator.  These instructions must reflect
the measurement procedures  found  in  the  EPA documents, "Interim Indoor
Radon  and  Radon  Decay  Product  Measurement   Protocols"   and  "Interim
Protocols  for  Screening  and  Follow-up Radon  and  Radon  Decay Product
Measurement".   They must be accepted  by,  and  on file  with  EPA  by  the
end of the follow-up test.
     Once  enrolled,  a  company must meet EPA's  minimum screening meas-
urement requirements for each method.  A company must meet all detector
and analysis result  deadlines  as listed on its  program schedule.    Ap-
plications,  detectors,  and analyses  reporting  forms  received after a
scheduled  deadline will not be considered  in the performance evaluation
process.   A  companyjs  detector(s). must be  tested  every round to main-
tain  its proficiency listing.
                        EXPLANATION OF ACRONYMS

Methods                                                 Units
AT  - Alpha-Track Detection   '                           (pCi/1)
CC  - Activated Charcoal Adsorption                      (pCi/1)
CR  - Continuous Radon Monitoring                        (pCi/1)
CW  - Continuous Working-Level Monitoring                (WL)
GR  - Grab Radon Sampling                                (pCi/1)
GW  - Grab Working-Level Sampling                        (WL)
RP  - Radon  Progeny  Integrated Sampling/RPISU            (WL)
Measurement  Units
pCi/1 - Picocuries  per  liter, radon gas measurement  units.
WL  -    Working-level,  radon progeny  measurement  units.
Others
DT  -  Detector(s) damaged or lost  through  no  fault of  the  participant

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                                                                  TABLE 1
                                                   MEASUREMENT COMPANIES BY SERVICE AREA


     * Company                             Measurement Method*                    * Company                             Measurement Methods
  Enviradon                                CC.AT
  914 Rolllngwood Drive
  Mt. Holly, NC  28120

       (7O4) 827-1293

+ NC Oept. of Human Resources              GR
  Radiation Protection Section
  7O1 Barbour Drive
  Raleigh, NC  27603-2008
       (919) 733-4283

  Radon Check                              CC
  2263 Coopersmith Square
  Reston, VA  22O91

       (703) 476-6810

  Radon Consultants, Inc.                  CC.AT
  4O12 N. 36th Street
  Arlington, VA  222O7

       703/624-6679 3O1/736-7O4O

  Thermo Scan                              CC
  1717 East 116th Street
  Box 7O5
  Carmal, IN  46O32
       (317) 846-46EE

* Univ.  of North Carolina Chapel Hill      CC
  Sch. of Pub. Health, Env Sci A Engr
  Rosenau Ha 11 2O1 H
  Chapel  Hill, NC  27614
       (919) 966-3840
   * More detailed Information on the measurement companies'  services  and past performances Is available upon request from your
       State Radiation Representative's Office.
   + Non-commercial  laboratory.
   0 Non-commercial  laboratory for State agency's assistance  only.

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                                                                TABLE 1
                                                 MEASUREMENT COMPANIES BY SERVICE AREA
   * Company
Sorensen Enterprises, Inc.
Radon Detection A Elimination Servi
886 West Hunt Road
Alcoa, TN  377O1
      (616) 984-1376
Southern Radon Services                  CC
1000 Johnson Ferry Road
Suite B-146
Marietta, GA  3O068
     800/637-2366,800/367-6184

Standor Radon Detection                  AT
E98 South Edgewood Avenue
Jacksonville, FL  322O5

     (904) 388-O284

TCS Industries                           CC
4326 Crestview Road
Harrisburg, PA  17112

     (717) 667-7O32

Teledyne Isotopes Midwest Lab.           CC
16O9 Frontage Road
Northbrook, IL  6O062

     (312) 664-O700

Teledyne Isotopes, Inc.                  CC
6O Van Buren Avenue
Westwood, NJ  O7676

     (2O1) 664-7070

Terradex Corporation                     AT
3 Science Road
GI onwood, IL  60426-1579

     (312) 766-7911
Measurement Methods

CC
     * Company
0 U.S. Environmental Protection Agncy
  Eastern Environ. Radiation Facility
  P. 0. Box 3009, 1890 Federal Drive
  Montgomery, AL  361O9
       (206) 272-34O2

+ Univ. of Texas Sen. of Pub. Health
  P. 0. Box 2O186
  1200 Herman Dressier
  Houston, TX  77226
.f.      (713) 792-4421

+ University of Pittsburgh
  Physics Dept. Radon Project
  3941 O'Hara Street
  Pittsburgh, PA  1626O
       (412) 624-4290

  Weston
  Weston Way
  West Chester, PA  1938O

       (216) 692-3O3O
                                NORTH CAROLINA
                                    American Radon Testers
                                    6706 Center Lane
                                    Office #1
                                    Falls Church, VA  22041
                                         (703) 379-6876

                                    Appalachian Environmental Testing
                                    Suite 326 Masonic Building
                                    106 South Union Street
                                    Danville, VA  24641
                                         (804) 792-1300
Measurement Methods

CC.GR
                                                                             CC
                                                                             CC
                                                                             GR.GW
                                            CC
                                            CW
 * More detailed information on the measurement companies' services and past performances Is available upon request from your
     State Radiation Representative's Office.
 + Non-commercial laboratory.
 0 Non-commercial laboratory for State agency's assistance only.

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                                                                TABLE 1
                                                 MEASUREMENT COMPANIES BY SERVICE AREA
     Company
Radon Management Company
4332 Gingham Court
Alexandria, VA  2231O

     (703) 96O-1321

Radon Measurement and Services
13131 West Cedar Drive
Lakewood, CO  8O228

     (3O3) 98O-6O88

Radon Research Group
P. 0. Box 1143
8 Cross Laurel Ct.
Germantown, MD  2OS74
     (301) 972-33O9

Radon Testing Corp. of America
RTCA
12-C West Main St.
Elmsford, NY  1O523
     800/4B7-2368,914/347-5O1O

Radon Testing Service
P. 0. Box 19426
Pittsburgh, PA  16213

     (412) 687-1533

Radon and Water Testing Service
1O86 Lafayette PC Road
Plain City, Ohio  43064

     (614) 873- 8821

Radontech, Inc.
1616 Walnut Street
Suite 2200
Philadelphia, PA  19103
     (216) 646-6661
Measurement Methods

CC
AT.CC
AT
CC
CC
CC
CC
   * Company
Real Estate Support Services, Inc.
8867 Pine Bluff Ct.
Eden Prairie, MN  66344

     (612) 941-7EB8
Roberts Environmental Services            GR,CW
Suite 1O9
411O Old Wake Forest Road
Raleigh, NC  276O9
     (919) 790-9378

Rogers & Assoc. Engineering Corp.         AT,CC,GR
616 East 4600 South
Suite G-2BO
Salt Lake City, UT  841O7
     (801) 263-160O

Ross Systems, Inc.                        AT,CC
Blairstown Professional Bldg.
R.D. 2, Box 1148
Blalrstown, NJ  O7826
     (201) 362-6671

Ryan Nuclear Labs                         CC
7O3O-D HuntIay Road
Columbus, OH  43229

     (614) 886-2962

Scientific Analysis, Inc.                 CC
6O12 Shirley Lane
Montgomery, AL  36117

     800-638-8348, 724 at Tone

Scientific Testing Associates             CC
Star Route, Box 124
Topping, VA  23169

     (804) 768-6728
Measurement Methods

CC
 * More detailed information on the measurement companies' services and past performances is  available upon  request from your
     State Radiation Representative's Office.
 + Non-commercial laboratory.
 0 Non-commercial laboratory for State agency's assistance only.

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                                                                TABLE 1
                                                 MEASUREMENT COMPANIES BY SERVICE AREA
   • Company
R.A.O. Service and Instruments Ltd.
60 Silver Star Blvd., Unit 208
Scarborough, Ontario Canada MlV 3L3

      (416) 298-9200
Radiation Protection Services, Inc.      CC
P. 0. Box 2395
Oarion, CT  06820

     (203) 324-7967

Radiation Safety Engineering, Inc.       CC
7713 South Butte Avenue
Tempo, AZ  86284

     (602) 897-9469

Radiation Safety Services, Inc.          GW
1E64 Ashland Ave.
Evanston, IL  6O2O1-4O7O

     (312) 866-7744

Radiation Service Organization           CC
P. 0. Box 1626
711 Gorman Avenue
Laurel, MD  2O7O7-O963
     (301) 963-2482

Radon Alert Detection Center             CC
P. 0. Box 323
Flourtown, PA  19O31

     800/346-6348,216/247-9197

Radon Ana lists                           CC
P. 0. Box 6O9
R.D. 2 Box 463
Livingston Manor, NY  12768
     914/292-2277 or 439-6111
Measurement Methods

RP
   * Company
Radon Analysis, Incorporated
P.O. Box 661M Fox Run
StewartsvllU, NJ  O8888

     (201) 479-6088
                                    Radon Detection Services,  Inc.            AT,CC
                                    P.  0. Box 419
                                    Old York Rd.  C/0 N.C.  Hunt Bldg.
                                    Rlngoes, NJ  O8661
                                     .    (201)  788-3080

                                    Radon Detection Services,  Inc., QA       AT.CC
                                    126 Fernhlll  Court
                                    P.  0. Box 768172
                                    Roswell, GA  30076
                                         (4O4)  993-1471
Measurement Methods

CC
                                    Radon Detection  Services,  Inc., MO
                                    608 Washington Blvd.  - Suite  3OO
                                    PO Box 1196
                                    Laurel, MD  2O7O7
                                         (3O1) 726-2901

                                    Radon Detection  Services,  Inc., PA
                                    1O11 Brookside Rd., Suite  27O
                                    PO Box 3309
                                    Allentown, PA 18106
                                         (216) 481-9666
                                    Radon  Gasbusters                         CC,CW
                                    613 Lyons  Avenue
                                    Irvington, NJ O7111

                                         (201) 376-371O

                                    Radon  Inspection Service                  AT
                                    787 E.  Glen Avenue
                                    Ridgewood, NJ O746O

                                         (201) 670-8821
                                          AT,CC,GR,GW,CW
                                          AT,CC,GR,GW,CW
 * More detailed information on the measurement companies' services and past performances is available upon request from your
     State Radiation Representative's Office.
 + Non-commercial laboratory.
 0 Non-comnercial laboratory for State agency's assistance only.

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                                                                  TABLE 1
                                                   MEASUREMENT COMPANIES BY SERVICE AREA
     • Company
  Key Technology, Inc.
  2503 Hollmandale Rd.
  Jonestown, PA  17038

       (717) 887-6476
  LEGIS Corporation                        CC
  2211 Saxon
  Houston, TX  77O18

       (713) 680-8883

  Lapteff Associates                       CC
  14611 Telegraph Road
  PO Box 415O
  Woodbridge, VA  22194
       (703) 491-6700

* Maine State Dept. of Human Services      CC
  Public Health Laboratory Station 12
  221 State Street
  Augusta, ME  04333
       (207) 289-2727

  Microbac Laboratories, Inc.              CC
  Erie Testing Laboratory Division
  2431 West 26th Street
  Erie, PA  165O6
       (814) 833-4790

  NODAR,  Inc.                              GW
  Route 6, Box 333R
  Athens, AL  36611

       (206) 729-1900

  National Radon Control, Inc.             RP
  197 Meister Ave
  Box 6342
  North Branch, NJ  O8876
       (201) 231-0844
Measurement Methods

CC
                                                                                  »  Company
                                   Nuclear Sources A Services, Inc.
                                   6711 Etheridge
                                   Houston, TX  77O87

                                        (713) 641-0391
                                   0. K. Rems Corp.                          CC
                                   174 Flock Road
                                   Mercervl Me, NJ  O8619

                                         (609) 688-9627

                                   Overman Associates/ AIR SCIENCES          CC
                                   P. 0. Box 376
                                   702 N. Lafitte Drive
                                   Bonne Torre, MO  63628
                                         (314) 662-7O2O

                                   Princeton Testing Laboratory              CC
                                   Princeton Service Center
                                   P. 0. Box 3108, U.S. Route 1
                                   Princeton, NJ  08643
                                         (609) 462-2037

                                   Product Analysis * Structural Test.       CC
                                   6800 Wales Road
                                   Northwood, OH  43619

                                        (419) 691-8484

                                   Pyramid Environmental Systems, Inc.       CW
                                   3O Oak Tree Lane
                                   Sparta, NJ  O7871

                                        (2O1) 729-9376

                                   R. S. Landauer, Jr. A Co.                 AT
                                   2 Science Road
                                   Glenwood, IL  60426-1686

                                        (312) 766-7000
Measurement Methods

CC
   • More detailed Information on the measurement companies'  services and past performances Is available upon request from your
       State Radiation Representative'* Office.
   + Non-commercial  laboratory.
   0 Non-commercial  laboratory for State agency's assistance  only.

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                                                                TABLE 1
                                                  MEASUREMENT COMPANIES BY SERVICE AREA
   • Company
Eberllne Analytical Corp.
P. 0. Box 3874
3636 Kircher Blvd., N.E.
Alberquerque, NM  8719O
     (505) 346-9921
Eberlin* Instrument Corp.                RP.CW
P. 0. Box 21O8
Airport Road
Santa Fe, NM  876O4-21O8
     (505) 471-3232

Electro Mechanical Concepts, Inc.        CC
13O Mountaineer Lane
West Miff I in, PA  16122

     (412) 276-2272

Electro-Kinetic Systems, Inc.            CC
701 Chestnut Street
Trainer, PA  19O13

     (216) 497-466O

Environmental Testing A Engineering      CC
9186 E. Kenyon Ave., Suite 190
Denver, CO  8O237

     (303) 722-2112

Enviroserv                               CC
15 Buckley Hill Road
Morristown, NJ  O796O

     (2O1) 285-1065

Gemini Research, Inc.                    AT,CC
61O1-0 Back lick Road
Annandale, VA  22003

     80O-8RADONO;703-941-0070
 Measurement Methods
B____*V>»^«
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                                                                    TABLE 1
                                                     MEASUREMENT COMPANIES BY SERVICE AREA
       * Company
 Measurement Methods
    * Company
NATIONAL
    ARIX Sciences, Inc.
    76O Horizon Drive
    Grand Junction, CO  81606

         (303) 242-6203

    Ablonlcs, Ltd.
    126O9 Kings Lake Drive
    Boston, VA 22091

         (703) 62O-3767

    Accurate Air Testing
    12O9 Piney Woods Drive
    Friendswood, TX  77646

         (713) 641-O391

    Airchek
    643 King Road
    P. 0. Box 10O
    Penrose, NC  28766
         800/267-2368,7O4/862-4O37

    Alpha Control
    6407 Good luck Rd.
    Rlverdale, MD  2O737

         (3O1) 474-O071

    American Atcon, Inc.
    11O6 North Market Street
    P. 0. Box 1347
    Wilmington, DE  19899
         (416) 828-2389
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 Amersham Corporation
 2636 South Clearbrook Drive
 Arlington Heights, IL  60006-4692

     (312) 693-6300

 Appalachian Environmental Testing
 Suite 326 Masonic Building
 106 South Union Street
 Danville, VA  24641
     (804) 792-1300

 Applied Health Physics, Inc.
 2986 Industrial Blvd.
 Box 197
 Bethel Park, PA  161O2
     (412) 663-2242

 Assay Services
 P. 0. Box 1266
 Friendswood, TX  77646

     (713) 641-O391

 Battelle
 Columbus Division
 606 King Ave.
 Columbus,  OH  43201-2693
     (614) 424-6424

 CMT, Inc.
2813 Rio Vista
Emporia, KS  668O1

     (316) 342-2760

EDA Instruments,  Inc.
6161 Ward Road
Wheat Ridge, CO  80033

     (800) 6E4-O5O6
 Measurement Methods

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     *  More detailed Information on the measurement companies' services and past performances  is available upon  request from your
         State Radiation Representative's Office.
     •»  Non-commercial  laboratory.
     0  Non-commercial  laboratory for State agency's assistance only.

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