United States        Eastern Environmental      RP/Ef RF 79 '
             Environmental Protection    Radiation Facility
             Agency          P.O. Boa 3009        March 1979
             Office of Radiation Programs  Montgomery AL 36109

             Radiation
xC'EPA       A Study of Radon - 222
             Released from Water
             During  Typical
             Household Activities

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                     EPA Review Notice

  This report has been reviewed by the Environmental Protection
Agency (EPA) and approved for publication.  Approval does not
signify that the contents necessarily reflect the views and
policies of the EPA, nor does mention of trade names or commer-
cial products constitute endorsement or recommendation for use.

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A Study of Radon-222 Released from Water

  During Typical Household Activities
           J. E. Partridge

           T. R. Morton

           E. L. Sensintaffar
Eastern Environmental Radiation Facility
      Office of Radiation Programs
  U.S. Environmental Protection Agency
             P. 0. Box 3009
      Montgomery, Alabama  36109
               March 1979
  U.S. ENVIRONMENTAL PROTECTION AGENCY
      Office of Radiation Programs
Eastern Environmental Radiation Facility
      Montgomery, Alabama  36109
                                            Technical Note
                                             ORP/EERF-79-1

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                          ABSTRACT
     Small quantities of radon-222 can be found in all ground water
from natural sources as a result of decay of radium-226 both in
water and the soils and soil matrix surrounding the water.  Radon in
drinking water has previously been considered a source of radiation
exposure primarily from an ingestion standpoint.  However, the EPA,
Office of Radiation Programs, is investigating the potential for
exposure to individuals from inhalation of gaseous radon released
from water.

     This report describes the results of a study to determine the
fraction of radon released from water during typical household
activities such as clothes washing, dishwashing, showering, etc.,
and estimates the potential radon concentration in air and result-
ing working levels in structures.
                              iii

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                               CONTENTS
                                                                      Page
Abstract	 i i i
List of Tables	  iv
List of Figures	   v
I.   Introduction	   1
II.  Objectives	   1
                                        •
III. Counting Technique	   2
IV.  Experimental Setup and Sampling Procedures	   2
V.   Resul ts...	   3
VI.  Modeling Radon in a Closed Structure	   7
VII. Summary and Conclusions	  10
References	  13
Appendices
     A.  Radon in Water Samp! i ng Procedures	 A-l
     B.  FORTRAN Program	 B-l
                                Tables
1.   222Rn in Water Supplies	   4
2.   222Rn Released by Clothes Washer	   6
3.   222Rn Released by Other Household Applications	   6
4.   Individual Water Usage Rates	   8
5.   Daily Composite Radon Source Term	   8
                                   iv

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                               Figures

                                                                       Page

1.   Daily radon concentration and working level with time	   9
2.   Sensitivity analyses	  11
3.   Average radon and working level variations with different average
     radon water concentrations	  12

1A.  Radon in water - sampling kit	 A-3
2A.  Radon sampling kit - close-up	 A-4
3A.  Connect tube to water supply	 A-5
4A.  Allow water to slowly collect in funnel	 A-6
5A.  Withdrawing water sample with syringe	 A-7
6A.  Eject air bubbles and excess water	 A-8
7A.  Inject sample into sample vial	 A-9

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I.    Introduction

          Radon-222 is an inert,  noble gas formed by radioactive decay of
     radium-226.   Radon-222 also  undergoes radioactive decay by emission
     of alpha particles with a characteristic half-life of 3.82 days (!)•
     Decay products of radon* include a series of short half-life radio-
     active isotopes including alpha, beta, and gamma emitters.  All
     progeny are  associated with  particulates.

          Small quantities of radon can be found in all  ground water from
     natural sources as a result  of decay of radium both in water and the
     rock and soil  matrix surrounding the water.   The concentration  of
     radon in ground water may far exceed that of radium in the water
     because gaseous radon can migrate from the solid matrix into under-
     ground aquifers.  Measurements of radon in water from selected  water
     sources, including primarily thermal springs, were recorded as  early
     as 1905 (2).  These measurements showed a large variation in radon
     concentration  between different thermal springs.  Radon in water
     from many other areas  has  been measured since that time, and the re-
     sults reported in various publications (3-6).  A summary of the find-
     ings from these and several  other studies was prepared by Duncan,
     et a!., for the U.S. Environmental Protection Agency (EPA) (7).   These
     reports indicate concentrations of radon in potable water supply
     systems ranging from 1,000 to 30,000 pCi/1.   Specific geographic areas
     shown to have  such high concentrations include Maine, North Carolina,
     Texas, Arkansas, Florida, and Utah.

          Radon in  drinking water has previously been considered a source
     of radiation exposure primarily from an ingestion standpoint.  However,
     the EPA, Office of Radiation Programs (ORP), is investigating the
     potential for  exposure to individuals from inhalation of gaseous radon
     released from  water by various household and commercial processes.
     Dose estimates in the literature have also been based on radon  progeny
     ingested with  water.  More recent data indicate that inhalation of
     radon and radon progeny may produce significantly higher exposures (7).
     To accurately  predict the potential  exposure from radon inhalation, it
     is necessary to have knowledge of the concentrations of radon in a
     water supply and what percentage of this radon is released by typical
     water uses,  i.e., showers, dishwashers, clothes washers, etc.  To
     obtain the latter information, the Eastern Environmental Radiation
     Facility (EERF) has investigated some typical residential water uses
     to determine the portion of radon released.

II.  Objectives

          The objectives of this  study were to measure the fraction  of
     radon released during typical household activities such as clothes
     washing, dishwashing, showering, etc., and to estimate the potential


* In this report, the term "radon" refers to radon-222.

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     radon concentrations in surrounding air and resulting working levels
     (WL)* in structures.

          To accomplish these objectives, the EPA, EERF mobile lab was
     outfitted with a clothes washer and dishwasher, and a field trip was
     made to Polk County, Florida.  Previous studies had shown elevated
     levels of radon in water which were associated with the phosphate
     deposits in the area.

III. Counting Technique and Calibration

          The concentrations of radon in water were determined by using
     a liquid scintillation technique similar to the procedure described
     by Prichard and Gesell (8).  The technique involves the introduction
     of 10 ml of water to be analyzed for radon into a liquid scintilla-
     tion vial containing 10 ml of liquid scintillation counting solution.
     The mixture is then sealed and agitated and held for three hours to
     allow the short-lived radon daughters to reach equilibrium before
     counting.  A single sample liquid scintillation counter was used in
     the mobile laboratory for sample analysis.

          Calibration of the counting system was accomplished by preparing
     several liquid scintillation vials with 10 ml of the mix and 10 ml of
     radium-226 in water solution of known concentrations.  These mixtures
     were then sealed and held for a minimum period of 30 days to allow
     the radon to reach equilibrium with the radium.  Concentration of
     radium-226 used for calibration ranged from 0.8 pCi/ml to 3.6 pCi/ml.
     The calibration factor, using a broad spectrum counting procedure was
     determined to be 10.1 counts/min/pCi.  The limit of detection for a
     50-min. count and 10-ml sample was determined to be 0.16 pCi (9,10).

IV.  Experimental Setup and Sampling Procedures

     A.   Supply Samples

               To determine the radon removal fractions by the various
          household applications, it was first necessary to determine the
          concentration of radon in the incoming water supply.  Supply
          samples were collected in accordance with the procedures out-
          lined in Appendix A.  By collecting the samples in this manner
          loss of radon to the air is minimized.  Five supplies were sam-
          pled and analyzed during this study.

     B.   Clothes Washer and Dishwasher

               Special plumbing was designed and constructed to allow
          the clothes washer and dishwasher installed in the EERF mobile
          laboratory to discharge in a normal mariner into a glass p-trap
* Working level is defined as any combination of radon daughters in one
liter of air that will result in the ultimate emission of 1.3 x 10s
MeV of potential alpha energy.

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          which was used as a sampling point.   Samples were collected from
          the p-trap by inserting a hypodermic needle through a rubber
          septum in the bottom of the trap.   The samples were injected into
          the sample vials as described earlier and analyzed using the li-
          quid scintillation counter.  Samples were collected from the trap
          following each of the various clothes and dishwasher wash and
          rinse cycles.  Other variables such as water temperature, amount
          of detergent added, and length of wash or rinse cycles were
          examined.  Identical studies were performed at several locations
          with varying concentrations of radon in the supply water.

     C.   Tub, Shower, Toilet, and Sink

               To determine the radon released by a tub, shower, toilet,
          and sink, three homes were selected which had water supplies with
          elevated radon in water concentrations.

               Radon released by the shower was determined by (1) operating
          the shower for several minutes with the drain open, (2) closing
          the drain, (3) turning off the shower, and (4) collecting a sam-
          ple from the bottom of the shower using a hypodermic needle as
          described earlier.  The concentration in this sample was compared
          to the concentration in the supply water before exposure to the
          atmosphere to determine the percent removed.

               A similar experiment was performed with a tub.  The tub was
          filled with water to a normal bathing level, and the water was
          agitated to simulate bathing.  All of the water was drained from
          the tub except a small portion from which a sample was collected
          with a hypodermic needle.  The concentration in this sample was
          compared with the supply concentration.

               Samples were collected from the toilet bowl and tank before
          and after flushing and refilling to determine the amount of radon
          released to the air by this operation.

               Radon released by running water into a sink was also deter-
          mined.  The sink was partially filled and the water agitated.
          The majority of the water was drained and a sample was collected
          from the remaining water with a hypodermic needle.

V.   Results

     A.   Supply Concentrations

               Radon-222 concentrations in the various water supplies sam-
          pled during this study are shown in table 1.  These five supplies
          were  all private wells that served from 1 to 10 families.  No
          information was available concerning the depth of the wells.

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                      Table 1
            Radon-222 in Water Supplies
                                      222Rn Concentration
Water Supply                              pCi/1 +20
1  Trailer park and residence            4,148 +203 (1)
2  Campground                            2,955+260(1)
3  Service station                       5,014+117(2)
4  Welding shop                          5,356 +327 (2)
5  Private residence                     8,649+442 (2)

 (1)  Mean of 10 samples.
 (2)  Mean of 4 samples.

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B.    Radon-222 Removal  Experiment

     1.   Clothes Washer

               The clothes washer used in these experiments had two
          cycles, regular and gentle.   The regular cycle had a maximum
          agitation period of 18 minutes followed by a short rinse
          cycle.   The gentle cycle was similar to the regular cycle
          except the degree of agitation was less.  The lengths of
          agitation and the water temperatures were variable on both
          wash cycles.   The lengths of the rinse cycles were preset in
          both cases and the rinse cycles used cold water.

               Radon released by clothes washing as a function of
          several parameters is shown  in table 2.  The length and
          degree of agitation appear to have a significant  effect on
          radon removal as evidenced by the difference in the regular
          and gentle cycle results and the difference in the 18-, 11-,
          and 4-minute agitation periods.  There also appears to be a
          difference in removal as a function of water temperature.
          The addition of soap to the  water did not appear  to have any
          significant effect.

     2.   Dishwasher

               The dishwasher used in  these studies had two wash cycles
          and four rinse cycles.  Samples were collected following both
          wash and rinse cycles.  The  results, as shown in  table 3,
          showed no significant difference in radon release between the
          wash and the rinse cycles.

     3.   Tub, Shower,  and Sink

               The three homes visited during this study had two
          showers and only one tub/shower combination.  The results of
          these experiments are shown  in table 3.  Water temperature
          again appeared to have significant effect on the  radon re-
          leased in the tub use.  Only one sink experiment  was per-
          formed during this study with the results given in table 3.

     4.   Toilet

               These experiments were  performed by flushing the toilet
          and allowing the tank to refill with fresh supply water.  A
          sample was collected from the tank and the toilet was flushed
          a second time.  After the tank and bowl had refilled, a sam-
          ple was collected from the bowl.  These radon release results
          for the two stages of flushing are shown in table 3.

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                             Table 2

                 222Rn Released by Clothes Washer

           Wash Parameter                          % Rn Released  + 2  a
Hot wash cycle (18 min.) with soap                     98.4 +_ 1.3
Hot wash cycle (18 min.) without soap                  97.9 +_ 2.7
Cold wash cycle (18 min.) with soap                    93.3 +_ 5.2
Cold wash cycle (18 min.) without soap                 93.5 +_ 3.4
Warm wash cycle (18 min.) with soap                    98.3
Cold wash cycle (11 min.) with soap                    91.4
Cold wash cycle (4 min.) with soap                     84.7
Cold wash gentle-cycle with soap                       78.7
Cold wash gentle-cycle without soap                    76.6
Cold rinse regular cycle                               80.9 +_ 17.4
Cold rinse gentle cycle                                62.2
                             Table 3

         222Rn Released by Other Household Applications

     Applications                                  % Rn Released ± 2 a

Dishwasher

     Wash cycle                                        97.7 +3.7
     Rinse cycle                                       98.5 +2.1

Tub

     Hot water                                         59.7
     Warm water                                        36.2
     Cold water                                        37.8

Shower  (warm)                                          71.2 +_4.7

Sink (warm)                                            28.3

Commode
     Tank                                              4.9+11.3
     Bowl                                              23-6 ±6-5

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VI.   Modeling Radon in a Closed Structure

          Since the quantity of radon-222 in potable water supplies  ranges
     over several  orders of magnitude,  a generalized model  will  be pre-
     sented with several examples of how certain variables affect the  amount
     of radon in a closed structure and the resulting daughter distribution.
     No attempt has been made to show the influence of running a central  air
     conditioning  system, window air conditioner or fan,  or any other  air
     moving device on the indoor radon  concentration except by varying the
     ventilation rate, i.e., air changes/hr.  Furthermore, radon daughter
     plate out and filtration are not included in this assessment which
     makes the working level estimates  conservative since working level
     values are dependent on daughter concentrations.

          A FORTRAN program (Appendix B) entitled WLSIMO  (working level
     simulation output) was developed to run on the EERF  PDP-11  minicomputer.
     This program  numerically solves a  series of first order linear  differ-
     ential equations known as the Batement equations. The output format
     includes radon concentration (pCi/1) and working level at time  (t),  and
     the average radon concentration (pCi/1) and working  level  for the total
     period of interest.  A sample input for WLSIMO can be found in  Appendix
     B.

          To estimate the buildup of radon and its progeny in a home from
     potable water supplies, the typical water usage rates in a household
     situation must be known.   These rates are given in table 4 in units  of
     gallons per day per person (gpdpp) with an average individual  usage
     rate of 20 to 80 gpdpp (11).   This information was combined with  the
     radon release data for each household water use (tables 2 & 3)  and
     typical radon in water concentrations to determine the potential  radon
     release for a typical  residence.

          As mentioned before, several  examples will be given to show  a gen-
     eral range of what might be expected in the buildup  of radon and  its
     daughters.  Table 5 describes a plausible situation  involving a family
     of four in which typical  household uses of water are included.

          The radon source term is expressed in units of  pCi/1-min.  This
     particular unit is needed in modeling the radon buildup in a closed
     structure.  In physical terms, it  can be thought of  as an incremental
     radon concentration increase in air per minute.  For example, a source
     term of 0.06  pCi/1-min represents  an increase in radon concentration in
     air of 0.06 pCi/1 every minute.

          Figure 1 demonstrates the daily cyclic nature of the radon concen-
     tration and working level resulting from a radon in  water concentration
     of 10,000 pCi/1.  The radon concentration and working level values are
     instantaneous values for a given time of day.  It was assumed that both
     values were zero at and before 7:00 a.m.  The maximum radon concentra-
     tion occurred at 9:00 p.m. with a  corresponding maximum working level
     value at about 10:00 p.m.  The average radon concentration and  working

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                               Table 4
                     Individual Water Usage Rates
        Radon Source                  Water Usage Rate (gal/day/person (11)
        Washing machine                          20-30
        Washing dishes                            8-10
        Bath                                     30-40
        Shower                                   20-30
        Toilet                                    4- 6
                               Table 5
                  Daily Composite Radon Source Term
                                                                   Source Term^
                            Source       Quantity (gal.)   %Rn     (pCi/1-min)
Start- 0700 (7:00 am)      Shower           25             .71
Stop - 0730 (7:30 am)      Toilet           12 (4 people   .28
                                                X 3 gal.)
                           Total             -              -         0.06
Start- 0900 (9:00 am)      Washing          25             .95        0.033
Stop-  1000 (10:00 am)     Machine
Start- 2000 (8:00 pm)      Bath             35             .50
Stop-  2100 (9:00 pm)      Toilet           12 (4 people   .28
                                                X 3 gal.)
                           Washing dishes    9             .98
                           Bath or shower
                             (2 children)   30             .60
                           Total             -              -         0.066
                     Grand Total           148 gal. (560 1) -            .- ,
*[radon] water * 10,000 pCi/1; house volume = 4.53X105!  (corresponds to a
                 2,000 ft2 house)
                                   8

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  CM
  CM
  CO
8
o>
O)
c
  CM
  CO
  O
  CO
  O
  O
  O
               [radon] H2O=10,000 pCi/l
                I       I      '      I   _  I
             house volume =4.35x 105I corresponding to 2000ft
            ventilation rate =0.25 air change/hr
  0000  0200  0400  0600   0800   1000   1200   1400   1600   1800   2000   2200   2400

                                    Time of Day

                  Figure 1.  Daily radon concentration and working level with time.

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     level  value for the 24-hr, period are 0.97 pCi/1  and 0.0074,  respec-
     tively.

          The effects of varying ventilation rates with constant house volume
     and varying house volumes with constant ventilation rates are shown in
     figure 2.  The average radon concentration and working level  decreases
     with increasing ventilation rate if the house volume is held  constant.
     Similarly, as the house volume increases, holding the ventilation rate
     constant, the average radon concentration and working level decreases.

          Figure 3 graphically exhibits the change in average WL and radon
     concentration with varying average radon water concentrations with a
     constant ventilation rate of one air change per hour and a constant
     volume of 3.4 x 10s 1 corresponding to a 1500 ft2 house.  As  the aver-
     age radon in water concentration increases, the average radon concen-
     tration in air and WL increase proportionately.  Figures 2 and 3 are
     based on the water usage presented in table 5.

          A recent paper by Gesell and Prichard (1978) (12) models radon in
     a home situation.  Results similar to the ones presented in this paper
     are given.  An even more recent modeling effort was undertaken by
     O'Connell and Gilgan (1978) (13) for radon bearing geothermal waters.
     Even though three different modeling approaches were used, the average
     radon concentrations predicted by each model (Gesell and Prichard, (12)
     O'Connell and Gilgan, (13) and this paper) are nearly the same if the
     same parametric values are used as input.

VII. Summary and Conclusions

          No attempt has been made to transform the radon concentrations in
     air and/or working level to dose and/or health effects, {jhe primary
     objective of this study was to determine radon release fractions for
     typical  water uses for use in modeling efforts to estimate the potential
     exposure levels in a typical residence^ The techniques used  for meas-
     urement of radon released from water seemed somewhat crude in some cases;
     however, the results agree well with other similar experiences and com-
     mon sense expectations, jjn general, the results indicate that agitation
     and heating both increase the release of gaseous radon from waterj
     There was some surprise that even a small amount of agitation, i.e.,
     running water into a sink or through a shower, did not cause complete
     release of all radon.  Additional measurements of this type will be
     performed as a part of a continuing study of radon exposure from
     natural  sources.  The EERF, in cooperation with many state and local
     health departments, is presently conducting a survey of radon concen-
     trations in selected public water supplies throughout the country.
                                   10

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             constant volume

(3.4 x 105I corresponding to 1500ft2 house)
     o
                                        constant ventilation rate

                                             (1 airchange/hr)
                                                            246

                                                              Volume (I) x 105
.5      1.0      1.5     2.0            o

  Air Change/hr


                                     Note: [Rn] H2O=10,000 pCi/l


                  Figure 2.  Sensitivity Analyses.
                                                                                   1.5
                                                                                   1.2
                                                                                   0.9 2.
                                                                                      Q.
                                                                                      CD
                                                                                   0.60
                                                                                   0.3
8

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                        [RrT] water,pCi/l
Figure 3.  Average radon  and working level  variations with
           different average radon  water concentrations.
                              12

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                               REFERENCES

 1.   Radiological  Health Handbook, PHS Publication No.  2016, p.  363,
     January 1970.

 2.   BOLTWOOD, B.  B.   On the radioactive properties of the water of the
     springs on the Hot Springs Reservation,  Hot Springs,  Arkansas;
     Amer.  Jour.  Sci.  4th Ser., V. 20, p.  128-132 (1905).

 3.   KURODA, P. K., P. E. DAMON, and H.  I.  HYDE.  Radioactivity  of the
     Spring Waters of Hot Springs National  Park and Vicinity in  Arkansas.
     Amer.  Jour.  Sci., Vol.  252, February 1954, pp. 76-86.

 4.   SMITH, B. M., W.  N. GRUNE, F. B. HIGGINS, JR., and J. G. TERRILL, JR.
     Natural Radioactivity in Ground Water Supplies in Maine and New
     Hampshire.  Jour. American Water Works Asso., Vol. 53, No.  1, January
     1961,  pp. 75-88.

 5.   ALDRICH, LESTER KYLE, III, M. K. SASSER, and D.  A. CONNERS, IV.
     Evaluations  of Radon Concentrations in North Carolina Ground Water
     Supplies, Dept.  of Human Resources, Division of Facility Services,
     Radiation Protection Branch, Raleigh,  North Carolina, January 1975.

 6.   O'CONNELL, M. F.  and R. F. KAUFMANN.   Radioactivity Associated with
     Geothermal Waters in the Western United States,  U.S.  Environmental
     Protection Agency Technical Note, ORP/LV-75-8A,  March 1976.

 7.   DUNCAN, D. L., T. F. GESELL, and R. H. JOHNSON,  JR.  Radon-222 in
     Potable Water, Proceedings of the Health Physics Society 10th
     Midyear Topical  Symposium:Natural Radioactivity in Man's Environment,
     October 1976.

 8.   PRICHARD, H.  M.  and T.  F.  GESELL,  Rapid Measurements of 2Z2Rn
     Concentrations in Water with a Commercial Liquid Scintillation Counter,
     Health Physics,  Vol. 33, No. 6, pp. 577-581, December 1977.

 9.   ALTSHULER, B. and B. PASTERNACK.  Statistical Measures of the Lower
     Limit of Detection of a Radiation Counter, Health Physics 9, 293, 1963.

10.   CURRIE, LOYD A.   Limits for Qualitative Detection and Quantitative
     Determination -  Application to Radiochemistry, Analytical Chemistry,
     Col. 40, No.  3,  March 1968, pp. 586-593.

11.   Water Use in the United States.  U.S.  Department of Interior.

12.   GESELL, T. F. and H. M. PRICHARD.  The Contribution of Radon in Tap
     Water to Indoor Radon Concentration.  Book of Summaries The Natural
     Radiation Environment III.  Houston, TX,  April  1978.

13.   O'CONNELL, M. F-  and G. A. GILGAN.  Radioactivity Associated with
     Geothermal Waters in the Western United States.   A Modeling Effort to
     Calculate Working Levels of Radon-222 and its Progeny for Nonelectrical
     Applications.  USEPA Technical Note.  ORP/LV-75-8B, 1978.

                                    13

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                              Appendix A


                  Radon in Water Sampling Procedures

A.  Sampling kits (figures 1-A and 2-A) are small lightweight carrying cases
    complete with all materials necessary for collecting potable water sam-
    ples for radon-222 analysis.

    Each kit contains the following equipment:

         1 - sampling funnel and tube with standard faucet fitting

         1 - slip-on faucet adapter

         2 - 20-ml syringes

         2 - 18-gauge, 2-inch hypodermic needles

         20 to 30 - glass scintillation vials with 10-ml solution, each

B.  Sample Collection

    1.   Attach the sampling funnel and tube to a faucet with either the
         standard faucet fitting or adapter (figure 3-A).

    2.   Slowly turn on the water and allow a steady stream to flow out
         of the funnel for approximately 2 minutes.  This purges the tube
         and assures a fresh sample.

    3.   Reduce the flow of water and invert the funnel (figure 4-A).  The
         flow should be adjusted to a level that does not cause turbulence
         in the pool of water contained in the funnel.  Allow excess water
         to spill over one edge of the funnel.

    4.   Examine the hose connection and tubing for air bubbles or pockets.
         If these are visible, raise or lower the funnel until they are re-
         moved.

    5.   Place the tip of the hypodermic needle approximately 3 cm under the
         surface of the water in the funnel and withdraw a few ml of water
         and eject this water.  Using this procedure, rinse the syringe and
         hypodermic needle two or three times.

    6.   Again, place the tip of the needle approximately 3 cm below the
         surface of the water and withdraw 12 to 15 ml  (figure 5-A).
         NOTE:  The water should be pulled into the syringe slowly to avoid
         extreme turbulence and collection of air bubbles.  If large air
         bubbles are noticed in the syringe, the sample should be ejected
         and redrawn.
                                   A-l

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 7.    Invert the syringe and slowly eject any small  air bubbles and
      extra water (figure 6-A).   Retain precisely 10 ml of water in
      the syringe.

 8.    Remove the cap from a vial  and carefully place the tip of the
      needle into the bottom of the liquid scintillation solution
      (figure 7-A).   Slowly eject the water from the syringe into the
      vial.  NOTE:   The water is  injected under the  liquid scintilla-
      tion solution to prevent loss of radon from the sample.   If the
      water is forced out of the syringe with much pressure, it will
      cause turbulence in the solution and could result in loss of
      radon.

 9.    Carefully withdraw the hypodermic needle from  the vial and re-
      place the cap.  The cap should be tightly secured to prevent
      leakage.

10.    Repeat the previous steps to obtain two separate samples from
      each source.   This completes the sample collection.
                                A-2

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Figure 1A.   Radon in water - sampling kit.
                      A-3

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Figure 2A.   Radon sampling kit - close-up.
                      A-4

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Figure 3A.   Connect tube to water supply.
                   A-5

-------
Figure 4A.   Allow water to slowly collect in funnel
                      A-6

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 ..
Figure 5A.   Withdrawing water sample with syringe.
                          A-7

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Figure 6A.   Eject air bubbles and excess water.





                     A-8

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Figure 7A.  Inject sample into sample vial
                    A-9

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                                 Appendix B

                              FORTRAN Program

C----     fcLSIMO.FTN
C-- —            A PROGRAM  TO SIMULATE THE BUILDUP OF RADON  AND ITS
C ----            DAUGHTERS  IN A CLOSF.D STRUCTURE.  THE  RUNGF-K Ul TA
C ----            MbTHOD  IS  USFD IN SOLVING A  SERIES OF  DIFFtRF NTI Al
C----            EQUATIONS.  (RATEMAN FQNSJ
C ----
         DIMENSION A (4) , XLD ( 4 ) , YL ( 4 ) ,DKL1(4) ,DFL2(4) ,PFL3(4) ,DtL4(4)
         DOUBLE PRECISION T,H
         LOGICAL *1 FNAME(30)
         LOGICAL *1 GNAME(30)
         DATA  XLO/1 .259b-4,.227, . 0259,. 035 2 /
         F(T,ARN)=P-(XLl+XL
  14
  lb     FORK AT C IkPUT  FILt? '$)
         HEAD(5,20,ERR=1000)LTH,FNA^E
  20     FOHKAT(0,30A1)
            N(UNJT=3 ,I>iAft = FNAMfcfHK:A.DOwLi , TYPF.s ' OT.D
         wRITE C5,200J
200      FOhMAK1 OUTPUT FILE? 'SD
         RE AD ( 5 , 2 1 0 , fc RR= 1 000 ) LTH , GN AMfc
210      FORMAI(0,30A1 )
                     )=0
          = 0.0
C        HsTIMh. INTERVAL  BFTWH-'.N CALCULA1 IONS ( NORMALLY  1.0  MIN ) ; TI A J>T =
c        TOTAL TIMKCMINJ ;>LI=LFAK AGK RATF(i/MiN);t-=suuRct'  TERNCPCI/L ^'a^.)
C        ;A( 1)=1NITIAL  RN-222 ACT I V1TY ( PC I/L ) : «L=IN IT1 AL  wOFKING LF.VFL;
C        AC/?) = 1MTIAL HAA  ACTI V IT Y (PC 1 /L ) ? A ( 3 ) = 1 M TI AL  PAP  ACT1 VIT* ( PCI/L )
C        ;A(4)=INI1IAL  PAC ACTI V 11 Y (PC 1 /L) ; w = 0 ; Ch = l IF  NFW  P IS HFSlFbD.
C        LL=1  IF ONLY ONb  P IS DF.SIRED  (I.E. CONSTANT  PJ
C
         RF AD(3,25)H,TLAS1,XL1 ,P, A(l) ,h
         RFAU(3,25)A(2) ,A(3) ,A(4)
         RF:An(3,100)i^,^M,LL
100      KlRfcAl (315)
  2b     FORMAT (bFK).O)
         DO 27 N=l,4
27        A(N) = t A(N)/XLD(N) )*?..22
         P=(P/XLD(1 ))*2.22
C        Tl = lNTfc.Fi»;EDIAT.E  T]Vf-,(VIN-l MIN ) ? XL2 = VRKTII ATIOM  RATE ( l/Vl N )
C        XLPA=PLA1EOU1  PA A ( 1 /!« J N ) : XLPH = PLATEOUT KAB ( J /NilN ) ?XLPC =
C        PLATF.OU1 RACd/MTN)
C
                                   B-l

-------
  30    KEAD(3,25)TT,XL2,XLPA,XLP&,XLPC
        READ NEW PCPCI/L  M1N)
        IF(LL.EQ.l) GO  TO 35
        IF(MM.GT.l) BEAD(3,25)  P
        IF(MM.GT.l) P=IP/XLD(1))*2.22
  35    CONTINUE:
        ARN=A(1)
        DRL1(1)=H*FIT,APN)
        DFLiCsDELKl )
        DfcLSll )=h*
        DFL2C = DKI.2(1)
        Dfc,L3(l ) = H*
        DEL3C=DF.L3(1)
  36    N=N+1
        IF(N.EQ.5)GO  TO  45
        YL(2)=XL1+XL2+XLD(2)+XLPA
        YLC4)=XL1+XL2^XLPC4)+XLPG
        B=AIN-1)
        C=A(N)
        DELl(N)=h*G(T,H,C,N)
        DELlHsDELKN)
        DEL2H=DEL2(N)
        DEL3R=DEL3(N)
        DFL.4(N)=H*GlT+H,R,C+nt:l,3R,N)
        GO TO 36
4b      TF(M.tQ.I) GUTO  110
        ACl)=A(l)*XLD(l)/2.22
        IF(JJ.hO.l)  GO TO  4ft
        GO TO 56
300     Am=A(2)*XLU(2)/2.22
        A(3)=A(3)*XLU(3)/2.22
        AC4)=A(4)*XLD(4)/2.22
        GO TO 47
46-     tvRlTE(l,50)Tf wL , A ( 1 )
47      IF(T.GT.TLAST) WPITF,(lf55)  A ( 2 ) . A ( 3 ) , A ( 4 )
55      KOPMAT(1X,3E12.4)
56      A(l)s(A(l)/XLD(lJ)*2.22
        If (T.GT.TLA&T) GO  TO 310
        GO TO 110
310     A(2) = (A(2)/XLL>m)*2.22
        A(3)=(A(3)/XL013))*2.22
        AC4)s(A(4)/XLD(4))*2.22
        GO 'JO 70
  50    FUF>MAT(lX,Fi0.3,3XfEi2.4,3X,&17.4)
110
                                 B-2

-------
         IF( JJ.tQ. 11 )  JJ =
         DO  frO fM=l ,4
60       A.(N) = A(N) + (Ofc.Ll(l
         T=I+H
         IMT.GT.TLAST) GOTU 300
         IF H .Gl .IT)  GO'lD  30
         GOTO  3b
  70     AVL=ASUM/(TLAS1/H-U. )
         WLAVsB&UM/CTLAST/H-H . )
99       FOPMAT(lX,2fr 12.4)
         CLOSKf UNIT=3)
         CLOSE: ( UN n = i )
         l*HJTb:(b, 80)
  80     F(lNf«ATl«  MORh. KJLKS
  85     KORMATIA2)
         IF( IhOkt;.EQ. ' Y  ')  GOTfi  14
loou
lOOb



1.0
0.0
0
419.0
449.0
0.06
539.0
0.0
599.0
0.033
1199.0
0.0
1259.0
0.066
1440.'0
0.0
w R I T t ( b ,
FORMAT ( '
GOTO 14
END

1440.
0.0
1
0.0
0.0

0.0

0.0

0.0

0.0

0.0

lOOb)
EhROK--F(t.



.0168
0.0

0.0
0.0

0.0

0.0

o.c

0.0

o.o


-ENTKK Flljf-. NAMK


Sample Input
0.0 0


0.0 0
0.0 0

0.0 0

0.0 0

0.0 0

0.0 0

0.0 0


•



.0


.0
.0

.0

.0

.0

.0

.0

                                                           o.o
                                       B_          aPO 1C7B —642-«3»/6a21. REGION NO.
                                      -o

-------