f	:	
      MANUAL OF PROTECTIVE
       ACTION GUIDES AND
       PROTECTIVE ACTIONS
      FOR NUCLEAR INCIDENTS
             Presented By

     The Environmental Protection Agency
                at

         NASA HEADQUARTERS
                date

           JUNE 10- II, 1998

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         SESSION I
WELCOME AND INTRODUCTIONS

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                               EPA 400-R-92-001
          MANUAL OF PROTECTIVE ACTIONS AND PROTECTIVE
        ACTIONS FOR NUCLEAR INCIDENTS WORKSHOP
                              NASA HEADQUARTERS
                                300 E STREET, S.W.
                                WASINGTON D.C.
                                JUNE 10- II,  1998
Wednesday, June 10,  1998
      8:30 -   9:00 am

      9:00 -  10:00 an

     10:00 -  11:00 am


     Hi00 -  12:00 pn
     12:00 -  1:00 pm


      1:00 -  2:30 pm



      2:30 -  4:30 pm



      4:30

Thursday, June 11,  1998


      8:30 -  10:00 am
     10:00

     11:00

     12:00

      1:00

      3:30
11:00 pm


12:00 pm


 1:00 pm


 3:30 pm


 4:00 pm
             Welcome and Introductions

             Overview (How the PAG manual ±B laid out)

             Rationale for PAG values (PAG Principles)

             Application and Interpretation of PAQs  (When to use them and
             how)

             Lunch

             Introduction to Dose Projection (Discussion of Terminology
             and EPA assumptions used)

             Implementation of Emergency Worker Dose Limits (Who are
             Emergency Workers and What limits apply)

             End of Day One
Development of DCFs and DRLs  (What are they and how do you
apply them)

Dose Projection for Early Phase  (Problem solving)

PAOs for Relocation (Assumptions made and rationale for use)

Lunch

Dose Projection for Relocation  (Problem solving)

Review and Wrap-up

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            SESSION 2
OVERVIEW OF BACKGROUND MATERIALS
    SUPPORTING THE WORKSHOP

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                   TOPICS
Response areas
Organization and content of the PAG Manual
and its major support documents

Exposure pathways

Incident phases
                                              2-1

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                                                PLUME TRAVEL
                                                  DIRECTION
2.  AR6A FROM WHICH POPULATION IS
                                  RELOCATED (RESTRKTTEO ZONE*.
                                                                              2-2

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        CONTENTS OF THE PAG MANUAL
CHAPTERS            SUBJECTS
   I          Background information

2, 3, & 4    PAGs for plume, ingestion, and
             relocation

5, 6, & 7    Implementation guidance for the
             3 PAG categories

   8          Reserved for recovery guidance
                                               2-3

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         CONTENTS OF THE PAG MANUAL
                       (cont'd)
APPENDICES     SUBJECTS


   A       Definitions of terms


   B       Risk of health effects from radiation
                                      •
   C       Rationale for selecting the early phase
           PAG values


   D       Rationale for food PAGs


   E       Rationale for Relocation PAGs

                                                 2-4

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       DOSES  N EXCESS OF THE L M TS
         FOR EMERGENCY WORKERS

Old limits of 75 and 100 rem present unacceptably high
risk for assignment.

No limit is needed for persons who volunteer for
higher doses if:
-   they are fully aware of the risks involved, and
-   they are lifesaving or preventing dose to a large
   population.

Chart of risks is provided (see page 2-12).
                                               3-19

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          BAS S FOR EMERGENCY WORKER
                    DOSE L M TS
                        (cont'd)
•  25 rem limit is justified for:

   -  life saving

   -  preventing substantial risks to populations

•  ICRP-26 recognizes 25 rem as a lifetime limit for
   specially justified circumstances.

•  Acute effects to adults will be avoided.
                                                   3-18

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      BAS S FOR EMERGENCY WORKER
                 DOSE L M TS
                    (cont'd)

10 rem limit for protecting valuable property

-   Some emergency situations justify dose limits higher
   than 5 rem.

-   ICRP-26 recognizes 10 rem as an annual limit for
   any single event for workers.

Higher limits are conditional.
                                              3-17

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 BAS S FOR EMERGENCY WORKER DOSE L M TS
                 (pp. C-22 to 24)
5 rem limit unless higher limit is justified

-  Occupational guidance should normally govern.

-  Limit emergency workers to nonpregnant adults.

-  Occupational limits for organs, extremities and lens of
   the eye should also apply.
                                                3-16

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    MAJOR CONCLUSIONS LEADING TO
       THE SELECTION OF I  REM AS
       THE PAG FOR EVACUATION
                 (p.C-19)

If sheltering is implemented to 0.5 rem at centerline,
and evacuation to I rem, the avoided dose from
evacuation will be about 0.5 rem.

Therefore, the PAG recommended for evacuation is
I  rem.
                                         3-15

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    MAJOR CONCLUSIONS LEADING TO THE
   SELECTION OF THE PAG FOR EVACUATION
                 (PP.C-I8&C-I9)
0.5 rem is the selected dose to be avoided.

-  This satisfies Principles I and 2.

-  Cost of going lower is not justified.  (Principle 3)

   Net reduction in average risk will occur
   (Principle 4).

-  Meets acceptable risk to the fetus established for
   occupational exposure.
                                                 3-14

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AVERAGE VERSUS CENTERLINE DOSE
            (p. C-12)
Centerline
Dose (rem)
0.5 to 1
1 to 2
2 to 5
5 to 10
Average Dose Avoided by
Stability Class (mrem per individual)
A
340
670


C
190
380
870

F
70
150
330
750
                                   3-13

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    CALCULATION OF RADIATION RISK
         VERSUS EVACUATION RISK
                  (p. C-10)

Estimated risk of death from transportation
= 9E-8/person mile.

Assume 100 mile round trip for evacuation.

Estimated risk of death from radiation
= 3E-4/person rem.

Calculate the equivalent risk (rem/100 miles).
                                            3-12

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            UPPER BOUNDS ON DOSE FOR EVACUATION
             BASED ON COST OF AVOIDING FATALITIES
                         (p. C-11 and E-2)
Accident
Category
SST- 1 b


SST-2


Atmospheric
Stability Class
A
C
F
A
C
F
Dose Upper Bounds4
Maximum (rem)
5
5
10
1
3.5
10
Minimum (rem)
0.4
0.4
0.8
0.15
0,25
07
a Based on an assumed range of $400,000 to $7,000,000 per life saved.
b SST means Siting Source Term. See page E-2 of PAG Manual.
                                                             3-11

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         AVERAGE RISK OF DELAYED HEALTH EFFECTS
                   IN THE U.S. POPULATION
                         (pp. B-19 to 25)
Health Effect
Fatal cancers
Nonfatal cancers
Genetic disorders
(all generations)
Effects per Person-rem
Whole
Body
2.8E-4a
2.4E-4
1 .OE-4
Thyroid
3:6E-5b
3.2E-4

Skin
3.0E-6
3.0E-4

a Risk to the fetus is estimated to be 5 to 10 times greater.
b Risk to young children is estimated to be about 1.7 times greater.
 Their dose is also about 2 times greater.
                                                            3-10

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        ACUTE HEALTH EFFECTS: CONCLUSIONS
                          (cont'd)

Dose              Acute Health Effect

10 rad        The dose level below which a fetus would not be
             expected to suffer teratogenesis.

5 rad        The approximate minimum level of detectability for
             acute cellular effects using the most sensitive
             methods.
                                                        3-9

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  ACUTE HEALTH EFFECTS:  CONCLUSIONS
                    (P-B-I7)

Dose             Acute Health Effect

50 rad       Less than 2 % of the exposed expected to
            show forewarning symptoms.

25 rad       Forewarning symptoms are not expected.
                                                3-8

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                   Based on minimal
                   medical care
               Intensive medical care may
               increase the dose threshold
               by :>0 percent,
      100     100    300    400     BOO
          WHOLE IODY ABSOKBIO 0081 (rid)

FIGURE B-1.  ACUTE HEALTH EFFECTS  AS A FUNCTION
           OP WHOLE BODY  DOSE.

                                              3-
7

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         RADIATION HEALTH EFFECTS
                 (Appendix B)

Acute (deterministic) health effects

Mental retardation

Radiogenic cancers

Thyroid disorders and cancers

Genetic disorders
                                                3-6

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                 BASIS FOR SETTING PAG LEVELS
                                 (p. 1-5)
          PRINCIPLE                     STRATEGY
(I)  Avoid acute health effects.               Stay below threshold dose.
(2)  Adequately protect against
    cancer and genetic effects
    under emergency conditions.
(3)  Optimize cost of protective
    action versus avoided dose.

(4)  Regardless of the above
    principles, the risk from a
    protective action should not
    itself exceed the risk from the
    dos  th t would be  voided.
Set PAG at this level unless
driven down by cost/risk
considerations (3), or up by
risk/risk considerations (4).

Use this principle only if the
the PAG value is driven down.

Use this principle only if the
PAG value is driven up.
                                                                        3-5

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          SHELTERING CONSTRAINTS
          (pp. 5-19 to 21 andC-l4to 16)

Sheltering provides only partial protection,

-  Protection factor decreases with time.

-  Ventilation rates vary.

-  Protection varies with building type.

-  Risk of shelter failure is significant.
                                                  3-4

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   BASIS FOR PROTECTIVE ACTION
DECISIONS DURING THE EARLY PHASE
               (p. 5-2)

Plant conditions and utility PARs
Dose projections
Field monitoring results
                                        3-3

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         PROTECTIVE ACTIONS
         FOR THE EARLY PHASE
                 (P- 1-4)

Evacuation

Sheltering

Access control

KI administration

Control of surface contamination
                                         3-2

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                      TOPICS
Protective action effectiveness
PAG Principles
Basis for PAG values and Emergency worker dose limits
                                                      3-1

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          SESSION 3
  RATIONALE FOR PAG VALUES
            AND
EMERGENCY WORKER DOSE LIMITS

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              INCIDENT PHASES
                (pp. I -2 to I -4)

Three phases of a radiological incident
-  Early
-  Intermediate
-  Late

In all phases, the PAGs are independent.

Refer to PAG Manual Page I -4.
                                               2-8

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     Airbbrm

     Plume •:•»
                       2-7
                           i Innalation
                           y  j**V*A
Gamma Rays
     Resi
tn
               ;estion
                •*-*——


                Beta_


                Particles
                       ^*-5ss*


              Deposited Paniculate Material




                    the Early Phase

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     MAJOR SUPPORT DOCUMENTS (cont'd)

Evaluation of Skin and Ingestion Exposure Pathways
(EPA 520/1 -89-016)

Evacuation Risks—An Evaluation
(EPA-520/6/74-002)

An Analysis of Evacuation Options for Nuclear
Accidents (EPA 52071 -87-023)

Economic Criteria for Relocation
(EPA 520/1 -89-015)
                                               2-6

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          MAJOR SUPPORT DOCUMENTS

•  Externa Dose-Rate Conversion Factors for Ca cu ation
   of Dose to the Public (DOE/EH 0070)

•  EPA Federal Guidance Report No. 11
   (EPA 52071 -88-020)

•  EPA Federal Guidance Report No. 12
   (EPA 402-R-93-081)
                                               2-5

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           SESSION 4
APPLICATION AND INTERPRETATION
              OF
   PROTECTIVE ACTION GUIDES
             AND
 EMERGENCY WORKER DOSE LIMITS
              FOR
        THE EARLY PHASE

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              MAIN TOPICS
Definitions and interpretations




Special dose quantities and concepts




PAG values and their application




The use of Kl for emergency workers




The impact of the changes to the guidance
                                           4-1

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              APPLICABILITY OF PAGs
                    (p. 2-1 & 2-2)
PAGs apply to all nuclear incidents or accidents except
nuclear war.
   Developed based on nuclear power plant accidents
   Dose limits also apply to all	

The implementation guidance applies primarily to nuclear
power plants.
                                                     4-2

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                 DEFINITIONS
                 (pp.  I -2 & A-3)

Protective Action Guide (PAG):

The projected dose to  individuals in the general
population that warrants protective action.

Projected Dose:

The calculated future dose that would be received by
individuals if no protective actions were taken.
                                                  4-3

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              PAG INTERPRETATIONS
                   (pp. l-l,&l-7)
PAGs are:
   Decision levels for public officials
   Used to minimize risk from an event which is occurring
   or has already occurred
                                                  4-4

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              PAG INTERPRETATIONS
               (pp. 2-1,4-1, 2-2, & I -6)
                       (cont'd)
PAGs are:
   Mandatory for planning
   -   but, professional judgment is required for their
      application

   Independent of the type or magnitude of the release
                                                  4-5

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              PAG NTERPRETAT ONS
                   (pp.  -6,  &2-2)
                        (cont'd)
PAGs are:
   A supplement to design safety of nuclear facilities
   Designed to protect all individuals in the population
                                                   4-6

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              PAG INTERPRETATIONS
              (pp. 1-6, 2-1, 2-4, & 2-10)
                       (cont'd)
PAGs are not:
   The basis for the size of the EPZ
   Dose limits
   Additive to other doses
                                                 4-7

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              PAG INTERPRETATIONS
                   (pp. I -7, & 2-1)
                       (cont'd)
PAGs do not:

•  Imply an acceptable level of dose for nonemergency
   situations.

•  Represent the boundary between safe and unsafe
   conditions.

•  Supersede Federal Radiation Council (FRC) Guidance,
                                                 4-8

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              PAG INTERPRETATIONS
                   (pp. A-2 & A-3)
                        (cont'd)
PAGs do not include:

•  Previous radiation doses.

•  Safety factors to account for uncertainties in dose
   projection procedures.
                                                   4-9

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       DOSE QUANTITIES USED
      FOR EMERGENCY RESPONSE
            (pp. B-1 & B-2)
Absorbed dose
Projected dose
Committed dose
                                       4-10

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         SPECIAL DOSE QUANTITIES
                 (p. B-1 & B-2)

Dose equivalent (DE)
-   Organ dose
-   Risk of cancer

Committed dose equivalent (CDE)
-   50 years

Effective dose equivalent (EDE)

Committed effective dose equivalent (CEDE)
                                              4-11

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    TOTAL EFFECTIVE DOSE EQUIVALENT (TEDE)

*  TEDE (an NRC term) means the sum of the deep dose
   equivalent from external gamma radiations (EDE) and
   the committed effective dose equivalent (CEDE) from
   internal exposures.

•  Plume PAGs are expressed as this sum.
   "TEDE" is not used in the PAG Manual

•  EDE from external sources is the same as NRCs term
   "deep dose equivalent"
                                               4-12

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                    EARLY PHASE PAGs
                   (pp. 2 5 to 2 8 & C 20)
                          (cont'd)

Projected dose (rem)       Action

I  to 5 TEDE        Evacuation (or, for some
5 to 25 CDE thyroid  situations, sheltering)
50 to 250 DE skin    should normally be initiated
                    at the lower end of the range.

25 CDE thyroid      Administer stable iodine (Kl)
from radioiodine     to the public in  accordance with
                    State medical procedures.
                                                        4-13

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          OTHER EARLY PHASE GUIDANCE
                    NOT PAGS
                   (pp. 2-4 to 2-9)

Projected dose (rem)      Action

<0.1 TEDE              No action based on risk
<0.5 CDE thyroid        from radiation dose.
<5 DE skin

0.1 to < I TEDE       Sheltering should be
0.5 to <5 CDE thyroid considered, but this is not a
5 to <50 DE skin        PAG for sheltering.
                                                4-14

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                DIFFERENCES IN
          EMERGENCY WORKER LIMITS
       AND PROTECTIVE ACTION GUIDES
•  Difference in justification
   Difference in time period of exposure
   Limits vs threshold for decisions
                                             4-15

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    EMERGENCY WORKER PROTECTION
         (pp. 2-9 to 13 and C-22 to 24)
Period of application of emergency worker limits

Emergency worker dose and occupational dose are not
additive unless required by license.

No guidance for keeping records of dose to emergency
workers

Protection of minors and fetuses
                                             4-16

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     EMERGENCY WORKER CATEGORIES
                   (p. C-22)

Designated by State and local authorities

Example categories:

-  Law enforcement and traffic control officials
-  Medical and public health personnel
-  Environmental monitors
-  Emergency vehicle operators
-  Utility, industrial, and institutional emergency
   workers
                                               4-17

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              PERSPECTIVES FOR
         EMERGENCY WORKER LIMITS
                (pp. C-22 to 24)

Apply the same dose limits as for occupationally
exposed workers wherever practicable.

Permit higher dose limits when required to prevent
substantial risks to populations or protect valuable
property.

Provide guidance for extreme emergencies.
-  Volunteers fully informed of risks
                                               4-18

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     DOSE L M TS FOR EMERGENCY WORKERS (p. 2- 0)
DOSE
LIMIT

5 rem
10 rem
25 rem
    ACTIVITY

          all
protecting valuable
   property
life saving or protecting
   large populations
>25 rem  life saving or protecting
             large populations
 CONDITION
lower dose not
   practical
lower dose not
practical

only on a voluntary
basis to persons
   fully aware of the
   risks.
                                                        4-19

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            Kl FOR EMERGENCY WORKERS
                   (pp. 2-11 and 2-13)
Kl is recommended if atmospheric releases include radioiodine
(no dose threshold).
State medical procedures determine its availability and proper
use.
                                                      4-20

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            SESSION 5
INTRODUCTION TO DOSE PROJECTION
              FOR
    PROTECTION OF THE PUBLIC
             AND
      EMERGENCY WORKERS

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           GENERAL APPROACH
           TO DOSE PROJECTION

Determine or estimate source term (Q) and
projected release duration (Tp).

Use atmospheric dispersion model to calculate time
integrated air concentration (Xin).

Use dose models to calculate projected dose (D) by
means of dose conversion factors (DCF).
                                             5-1

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               GENERAL APPROACH FOR CALCULATING
                             PROJECTED DOSE
Measure or calculate environmental
concentrations.
Multiply by duration of exposure to get time
integrated concentration (Xin) for each
nuclide or group of nuclides.
Multiply each Xin by the appropriate DCF to
get TEDE or thyroid dose from each nuclide
or group of nuclides.
Sum TEDEs over all nuclides or groups of
nuclides and su  thyroid doses to get
projected doses co  parable to PAGs.
Concentrations may be for indivi-
dual nuclides or may be grouped
by iodines and noble gases.
True Xh can be calculated if the
total release is used. Not used with
measured concentrations.
Use DCFs from PAG Manual
Table 5.1 for TEDE and 5.2 dose
for CDE to thyroid from single
nuclides. For groups of nuclides,
DCFs must be calculated.  A DCF
for participates, as a group, is not
practical.
                                                                            5-2

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     NEEDED SOURCE TERM INFORMATION
Gross noble gas, radioiodine, and participate release
rates
                       or

   curies per second of each radionuclide

Release height  (release point information)

Estimated release duration
                                                 5-3

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      NEEDED METEOROLOGY
Wind speed,
Wind direction
Stability Classes




Mixing depth




Predicted changes
Precipitation




                                          5-4

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     GAUSSIAN DISPERS ON EQUAT ON
      Xu
                             2a
                     n a a
                         y
For a ground level release, release height (h) = 0,

  At the centerline, the lateral distance (y) = 0.

             Xu           1
                       n a a
                           y
                                               5-5

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              BASIC DOSE EQUATION
Th  b sic dose equ tion is:
                   D = Xin - DCF
D    =  Dose (rem)

Xln =  Time integrated concentration in air
         (uCi • cm"3 • h)

h     =  duration of exposure (hours)

DCF  =  Dose conversion factor
         (r m p r uCi • cm"3 • h)
                                                   5-6

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       NEEDED INFORMATION FOR
          DOSE CALCULATIONS

Radionuclide air concentration (X)

Expected duration of exposure (Tp)

Dose conversion factors (DCF)

Dose projection procedures
-   computer programs
-   RASCAL
                                          5-7

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   INFORMATION NEEDED TO SUPPORT
     PROTECTIVE ACTION DECISIONS
Total effective dose equivalent (TEDE).

Committed thyroid dose (CDE).

Measurements of plume gamma rate.

Measurements of gross radioiodine concentrations.
                                          5-8

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               TIME INTEGRATED
           AIR CONCENTRATION, Xin

  Air concentration times projected exposure time,
            X(uCi/cm3) • Tp(hour) = Xin
•  Permits addition of the dose conversion factors over
   the three exposure pathways.
                                               5-9

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            TIME INTEGRATED
        AIR CONCENTRATION, Xin
                   (cont'd)


High concentration for short time


Low concentration for long time.


Symbol: Xjn


Matches units of EPA's dose conversion factors.
                                           5-10

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               TIME INTEGRATED
           AIR CONCENTRATION, Xin
                     (cont'd)
PROBLEM ONE
•  Xe-133 air concentration is  I.OE-4 uCi/cm3,
•  Expected duration of air concentration is 2 hours.

•  Xin equals ??????  (uCi • cm'3 • h).
                                              5-11

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               T ME INTEGRATED
           A R CONCENTRAT ON, Xin
                      (cont'd)

PROBLEM TWO

•  Xe-133 air concentration is 5.0E-5 uCi/cm3.

•  Expected duration of this air concentration is 240
   minutes.

•  Xin equals ??????  (uCi • cm'3 • h).
                                              5-12

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              TIME INTEGRATED
           AIR CONCENTRATION, Xjn
                     (cont'd)

SOLUTIONS TO PROBLEMS I AND 2

• Xin = (air concentration) (expected exposure time)

• Xin = (I .OE-04 uCi/cm3) (2 h)
     = 2.0E-04 uCi • cm'3 • h

• Xin = (5.0E-05 uCi/cm3) (240m/60m/h)
     = 2.0E-04 uCi • cm'3 • h
                                            5-13

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              DCF DEFINITION
                  (p. A-1)
Dose Conversion Factors (DCF) change
environmental concentrations (or time integrated
concentrations) to dose.
Dose units (rad = rem)
EPA DCF unit:  rem per uCi • cm  • h
                                            5-14

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      PARAMETERS THAT AFFECT DCFs
Physical characteristics
Chemical characteristics
Breathing rates




Assumed deposition velocities




Biological system clearances
                                             5-15

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   ASSUMED VALUES FOR CALCULATIONS

Breathing rate = 1.2 m3/h

Deposition velocity   EPA          RASCAL
-   Iodine           I cm/s        0.3 cm/s
-   Participates       0.1 cm/s      0.3 cm/s

Gamma shielding factor due to ground roughness
EPA  =   I       RASCAL default  =  0.7

Public exposure to deposited materials before
relocation is 4 days (96 h)
                                            5-16

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       DOSE CONVERSION FACTOR TABLES
            (TABLE 5-1 AND TABLE 5-2)

•  Table 5-1: Dose Conversion Factors and Derived
   Response Levels for Combined Exposure Pathways
   During the Early Phase of a Nuclear Incident.

•  Table 5-2: Dose Conversion Factors and Derived
   Response Levels - Inhalation of Radioiodine.

•  Refer to EPA Manual
                                                5-17

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                SKIN DOSE
DCFs for skin are not provided for early phase.
Skin dose is not expected to be controlling.
Skin dose is controlled by bathing and changing
clothing.
                                              5-18

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    USING DCFs FOR COMBINED PATHWAYS
                   (TABLE 5-1)

GIVEN:
-  The concentration of tritium (H-3) in a plume is
   5E-3 Ci/m3.

   Exposure to plume expected for 3 hours.

PROBLEM:
-  What is the time integrated air concentration?
-  What is the dose conversion factor?
-  What is the projected dose?
-  What kind of dose is it?
                                                 5-19

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     US NG DCFs FOR COMB NED PATHWAYS
                   (TABLE 5- )
                      (cont'd)

SOLUTION:  Calculate Xjn and look up the DCF.

•  Xjn = (air concentration) (expected exposure time)
      = (5E-3 uCi/cm3) (3 hours)

•  Xin= l.5E-02uCi-cm-3-h

•  DCF for tritium from Table 5-1 is
   7.7E+01 rem per uCi • cm"3 • h
                                               5-20

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     USING DCFs FOR COMBINED PATHWAYS
                    (TABLE 5-1)
                       (cont'd)

•  Projected dose = Xin times DCF
                        or
(I.5E-2 uCi • cm"3 • h)(7.7E+l rem per uCi • cm"3 • h)

•  Projected dose = 1.2 rem

•  This projected dose is considered to be total effective
   dose equivalent (TEDE).  Why?
                                                 5-21

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      US NG DCFs FOR COMB NED PATHWAYS
                    (TABLE 5- )
                       (cont'd)


THE PROJECTED DOSE IS THE TEDE BECAUSE:


•  DCF is based on committed effective dose equivalents.

•  All significant early phase exposure pathways are
   included.


•  All significant radionuclides are included.
                                                 5-22

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                  SUMMARY
                  n

            D = S  DCF • X
                          i  in, i
      = DCF for radionuclide (i)
n     = Number of radionuclides present
Xin,i   = The time integrated concentration of

        radionuclide (i)
                                                5-23

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          SESSION 6
     IMPLEMENTATION OF
EMERGENCY WORKER DOSE LIMITS

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                  MAIN TOPICS
   Emergency workers




   Relative importance of exposure pathways
   Inhalation dose control methods
   PAG Subcommittee guidance
•  Dose for the record
                                                6-1

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            EMERGENCY WORKERS
                    (P- 2-9)

State responsibility for defining emergency workers

Example assignments

-  Law enforcement/traffic control

-  Radiation protection

-  Transportation services
                                                6-2

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          EXPOSURE PATHWAYS FOR
            EMERGENCY WORKERS

External gamma radiation
   Plume
-  Groundshine

Inhalation from the plume and resuspended materials
-  Plume inhalation may be the major pathway

External beta radiation
-  Plume
-  Groundshine
   Deposited materials on skin and clothing
                                               6-3

-------
    NHALAT ON OF RESUSPENDED MATER AL

R susp  sion rat s
-   Empirical values range from I0~5 to IO"9 m"1

Importance of pathway

   Plume phase

-   Post plume phase

-   For example, at IO"5 m"1, I mR/h yields about 0.05 mrem
   CEDE from inhalation
                                                6-4

-------
EXAMPLE DOSES FROM A REACTOR ACCIDENT
RTM-93 CASE 5; Gap release for one hour; Late release @ 100 % par
  No Spray; No protective action;  o rain; Met cond. was not
 1,000
   100
                                      Rem Versus Distance

                                      — Thvroid Dose
      1
 2         5

Dist oe (mil  )
10
                                                  6-5

-------
   EXA  RLE DOSES FRO  A REACTOR ACCIDENT
  RT -93 CASE 16, Severe core damage; 100% per hour leak rate;
No spray; o ra'n; No protective action;  et Cond. was not Spec fed.
  100,000
   10,000
 Or  1,000
     too
                                         Rem Versus Distance

                                         -~ Thyroid Dose
        1
 2        5

Distanc  (mile )
10
                                                      6-6

-------
        INHALATION DOSE CONTROL
            USING RESPIRATORS

Mentioned, but not promoted by EPA or FEMA

Effectiveness
-  Filter type
-  Air supplied type

Advantages
-  Protects workers from inhalation dose.
-  Dose control by dosimeter is simple.
                                              6-7

-------
        NHALATION DOSE CONTROL
             US NG RESP RATORS
                    (cont'd)

Disadvantages
-  OSHA requirements
   •   Fitting and testing
   •   Training
   •   Medical examinations
-  No beards
-  Reduced vision, communication, and efficiency
-  Discomfort
-  Logistics
                                              6-8

-------
         PAG SUBCOMMITTEE GUIDANCE
                 DATED JULY 1994

ISSUE:   How should the dose to emergency workers,
        especially those exposed to a radioactive plume,
        be monitored and controlled to meet the EPA
        dose limits in terms of total effective dose
        equivalent (TEDE)

•   Guidance:
   -  Relates to accidents at nuclear power plants
   -  Based on current practices
   -  Other approaches may be acceptable
                                                 6-9

-------
       PAG SUBCOMMITTEE GUIDANCE
                  (CONTINUED)

Maintain 5 rem TEDE limit where practicable.

The primary activities for emergency workers within an
airborne plume will be:
-  Protection of valuable property,
-  Protection of large populations, and
-  Monitoring.

States should maintain flexibility in dose limits
                                               6-10

-------
       PAG SUBCOMMITTEE GUIDANCE
                    (cont'd)

Doses up to 10 and 25 rem (and above) should be
accepted and planned for.


DRDs may be used to estimate inhalation dose.

Use of Kl is recommended.


Flexibility in control procedures is granted.


Three acceptable options are presented.
                                              6-11

-------
   OPTIONS FOR ADJUSTING EMERGENCY WORKER
         GAMMA DOSE LIMITS TO ACCOUNT
      FOR SIGNIFICANT PARTICULATE RELEASES
  Options1
 Evacuation Phase
  Post-Evacuation Phase
      I
No adjustments
Adjust, if necessary
             Fixed admin, limit
             set prior to Emrg.
                 Adjust, if necessary
             Contextual
             adjustment based
             on plant data
                 Contextual adjustment
                 based on plant and
                 environmental data
lOth  r options may be co sid r d
                                                 6-12

-------
                  OPTION ONE

Control only whole body gamma and thyroid dose
during evacuation.

Rationale
   Not practical to rotate workers
   Inhalation dose is controlled for tasks after evacuation,
   Evacuation may be completed before plume    arrives,

Disadvantages
   Higher risk of over-exposure compared to other
options
                                                     6-13

-------
                 OPTION TWO

 Pre-established administrative limits

Rationale
-  Easy to implement
-  Will meet limits for most probable accidents

Disadvantages
-  May not provide adequate control for the most
   severe accidents
-  Possible discontinuity between States
                                                 6-14

-------
         DOSIMETER ADJUSTMENT FACTORS
Accid nt
Category
BWR-I
PWR-I
BWR-3
PWR-3
PWR-5
PWR-7
Adjustme t Factors3
With Kl
13 to 29
8 to 16
3 to 7
4 to 8
1.4 to 2
1 to 2
Without Kl
16 to 37
1 1 to 26
5 to 12
6 to 14
3 to 6
1 to 2
a Calculated for distances ranging from I to 25 miles, stability classes ranging
from A to F, and for 13 hours of exposure.
                                                       6-15

-------
                OPTION THREE
Calculate contextual mission limits applicable to the
accident in progress.

Rationale
-  Can use same data as for dose projection
-  Mission limits would be more defendable.

Disadvantages
-  Variable limits may be confusing to implement.
-  Necessary data may not be available.
                                                6-16

-------
   RETROSPECTIVE EVALUATION OF DOSE
              FOR THE RECORD
Applicable to emergency workers who are exposed to
an airborne plume containing iodines and/or participate
materials
Kl administration affects the evaluation.
                                             6-17

-------
     RETROSPECTIVE EVALUATION OF DOSE
               FOR THE RECORD
                    (cont'd)

Based on dosimeter readings (primarily TLD) and
-  Release composition
-  Environmental data (importance of air samples)

Or based on dosimeter readings and
-  Release composition
-  Whole body counts
-  Bioassay
                                              6-18

-------
      RETROSPECTIVE ANALYSIS USING
    RELEASE AND ENVIRONMENTAL DATA

Need measured dose rates and air sample data.

Dose rate measurements by air sampling teams relate
air concentrations to  dosimeter readings.

Calculations of ratio of exposure  rate to air
concentration allows worker dosimeter readings to be
related to TEDE - becomes official record.
                                             6-19

-------
                     RETROSPECTIVE - PROBLEM

Monitoring data at location A:
GM counter (closed beta shield, I  m) - 950 mR/h
GM counter (open beta shield, I m - open window pointing up) - significantly higher

Air sample is collected at location  A and sent to the laboratory for analysis. The laboratory reports
the following results:

     Ce-!4l     I.Oe-05  uCi/cm3
     Ba-140     I.Oe-04  uCi/cm3
     Cs-134    I.Oe-05  uCi/cm3

WHAT CONCLUSIONS CAN BE REACHED IMMEDIATELY FOR LOCATION A?

WHAT ARE THE FOLLOWING FROM A  I HR EXPOSURE?

     IMMERSION PLUS DEPOSITION DOSE (EDE)?
     INHALATION DOSE (CEDE)?  (See WORK SHEET on VG 6-22.)
     TOTAL DOSE (TEDE)?

WHAT IS THE DOSE TO EMERGENCY WORKERS EXPRESSED AS TEDE PER ROENTGEN AS
READ ON A DOSIMETER?


                                                                         6-20

-------
               RETROSPECT VE - PROBLEM  SOLUT ON

Immediate conclusions:

     There had been a release of radioactive material .

     The plume was present.

     Particulates were present.

     Actual risk could be much higher than implied by dosimeter readings.

Compare DCFs from plume shine versus ground shine for Cs-l 34. (The DCF for deposited
materials assumes persons remain 96 hours (4 days) at this location - correct for this).

     The deposition dose is not significant because the  I hr DCF is small compared to the
     immersion DCF.

Assuming "mR" is approximately equal to "mrem", the whole body dose rate from gamma radiations
(EDE/h)  is:
                                  950 mrem/h

Gamma dose (EDE) due to a I hour external exposure to the plume and groundshine
                     950 mrem/h • I h = 950 mrem = 0.95 rem


                                                                               6-21

-------
                 PROBLEM SOLUTION WORK SHEET
Problem Emergency worker    Projected Dose at Location A  from inhalation



Nuctide(s)


Ce-141
Ba-140
Cs-134


Air
Concentration
(X)
(uCi/cm3)

I.OE-05
I.OE-04
I.OE-05


Projected
Exposure
Time
(h)





Integrated
Air
Concentration
(XJ
(uCi • cm "3 • h)






DCF from
Table 5-4
(rem per
uCi • cm"3 • h)
•



Totals >
Inhalation
Committed
Effective Dose
Equivalent
(CEDE)
(rem)
•



                                                                    6-22

-------
                            PROBLEM SOLUTION
                                 (cont'd)

Total projected dose (TEDE)  to worker for nominal  I hour exposure to plume:
               0.95 rem (EDE) + 1.12 rem (CEDE) -I- 0.00 (EDE) =
                              2.07 rem (TEDE)

Nominal expected increase in dosimeter reading after I hour is:

                 0.95 rem (EDE) due to gamma from the plume +

          approximately 0.00 rem (EDE) due to  gamma from ground shine

                    total is 0.95 "R" recorded on dosimeter

0.95 "R" Dosimeter reading is equatable to a total  dose for the record:
                              2.07 rem (TEDE)

Retrospective dose for the nominal worker record:

              ach 1.0 "R" on dosimeter is quivalent to 2.2 rem (TEDE)
                                                                            6-23

-------
            FACTORS THAT MAY
       AFFECT DOSE CALCULATIONS

Insufficient air sample and exposure rate data

Ground shine becomes important.

Emergency workers get significant doses outside the
plume.

Emergency workers do not take Kl.

Emergency workers use respirators.
                                            6-24

-------
          PLAN CHANGES NEEDED
        TO SUPPORT OPTIONS I OR 2
Specify the administrative dose limits for evacuation
support.
Specify procedures for dose control after evacuation is
complete.
                                             6-25

-------
          PLAN CHANGES NEEDED
           TO SUPPORT OPTION 3

Specify procedures for contextual determination of
administrative dose limits.
-  Calculation models to be used
-  Data needs
-  Sources of data

Identify communication procedures and equipment.

Procedures for changing the administrative limits if
applicable
                                              6-26

-------
   GU DANCE APPLICABLE TO ALL OPT ONS

Other options may be se ected.
-   FEMA will review written proposals.

FEMA recommends admin, limits of 2 R or more.

Need procedures for:
   Retrospective dose determinations
-   Training

Existing dosimetry systems are acceptable.

Kl use is recommended.
                                               6-27

-------
  SESSION 7
DEVELOPMENT
     OF
DCFs AND DRLs

-------
        IMPLEMENTATION OF PAGS

Must compare a projected TEDE or CDE to the
applicable PAG

BASIC DOSE EQUATION

-   Dose (TEDE or CDE) = Dose Rate x Time

-   Dose Rate = Concentration x Conversion
   Factor

-  Dose = Time Integrated Concentration x DCF
                                         7-1

-------
                   DEFINITIONS

•  Dose Conversion Factor (DCF): A value that
converts an environmental level to dose.
                                        -3
-  Tabulated in units of: rem per uCi • cm  • h

Derived Response Level (DRL): Calculated
environmental level that corresponds to a particular
PAG.

-  Tabulated in units of:  uCi •  cm"3 • h
                                                 7-2

-------
                PATHWAYS
          (PAG Manual - Section 5.6)

Three exposure pathways are included:
- Gammas from the plume (immersion)
- Inhalation from plume
- Gammas from ground shine (deposited
radionuclides)

Pathways considered, but not included:
-  Beta due to skin deposition
-  Inhalation of resuspended materials
-  Beta from the plume
                                             7-3

-------
   SUPPORTING DOCUMENTS FOR DCFS

"External Dose-Rate Conversion Factors for
Calculation of Dose to the Public" (DOE/EH 0070)
-  Needed for plume and ground shine
"
 Limiting Values of Radionuclide Intake and Air
Concentration and, Dose Conversion Factors for
Inhalation, Submersion and Ingestion" (FGR-I I)
EPA 520/1-88-020 (September 1988).
-  Needed only to modify EPA DCFs for inhalation
                                            7-4

-------
               TIME INTEGRATED
           AIR CONCENTRATION, Xin

   Air concentration times projected exposure time,
            X(uCi/cm3) • Tp(hour) = Xin
•  Permits addition of the dose conversion factors
over the three exposure pathways.
                                               7-5

-------
EXTERNAL EXPOSURE TO GAMMA RADIATION
             FROM THE PLUME
                (Section 5.6.1)

 Table 5-3 (PAG manual, beginning on P. 5-25)

 Gamma radiation due to immersion.

 Conservative if plume is overhead.

 Semi-infinite source assumption.
                                           7-6

-------
EXTERNAL EXPOSURE TO GAMMA RADIATION
             FROM THE PLUME
                   (cont'd)

 DCFs yield effective dose equivalent (EDE).


 Based on DOE/EH-0070; EPA FGR # 12.


 Short-lived daughters are accounted for.
                                           7-7

-------
Table 5-3:  Dose Conver ion Factor (DCF) and Derived Re ponse
          Leve s (DRL) for Externa Exposure Due to mmer ion in
          Contaminated Air
Radionuclide
 DCF
 rem per
              uCi • cm  • h
DRL
 uCi
cm
   -3
 H-3
 C-14
 Na-22
 Na-24
 P-32
O.OE+00
O.OE+00
I.3E+03
2.7E+03
O.OE+00
PAG M nu I - beginning on p g  5-25
  O.OE+00
  O.OE+00
  7.8E-04
  3.7E-04
  O.OE+00
                                                       7-8

-------
       INHALATION FROM THE PLUME
                (Section 562)

Table 5-4 (PAG manual, beginning on 5-31)

Inhalation of radioactive participate material

Alpha, beta and gamma emitters

Chemical and physical form that yields the highest
dose
                                              7-9

-------
       INHALATION FROM THE PLUME
                (Section 5.6.2)
                   (cont'd)

Committed effective dose equivalent (CEDE)


Radionuclides may remain in the body,


50 year time frame for dose


Federal Guidance Report No. 11


Standard  Person
                                             7-10

-------
Table 5-4:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for Doses Due to Inhalation
               Lung      DCF           DRL
Radionuclide    Class      rem per      uCi • cm"3 • h
                       uCi • cm"3 • h
 H-3           V          7.7E+OI            I.3E-02
 C-14       LORGC3    2.5E+03             4.0E-04
 Na-22         D          9.2E+03            I.IE-04
 Na-24         D          I.5E+03            6.9E-04
 P-32          W         I.9E+04            5.4E-05

aL ORG C denotes labelled organic compounds

PAG Manu I - b ginning on pag  5-31
                                                                7-11

-------
Table 5-4:   Dose Convers'on Factors (DCF) and Derived Response levels
           (DRL) for Doses to the Thyro'd Due to Inhalat'on
               Lung       DCF           DRL
Radionuclide    Class       rem per       uCi • cm"3 • h
                        uCi • cm"3 • h
 Te/l-132       W/D       2.9E+05             I.8E-05
 1-125         D         9.6E+05            5.2E-06
 1-129         D         6.9E+06            7.2E-07
 1-131         D          I.3E+06            3.9E-06
PAG Manual - beginning on page 5-35
Also see Table 5-2 on page 5-15
                                                                 7-12

-------
EXTERNAL DOSE FROM DEPOSITED MATERIALS
                (Section 5.6.3)

 Table 5-5 (PAG manual, beginning on 5-37)

 Gamma radiation following deposition

 Radioiodine and particulates from a plume

 Assumes 4-day exposure

 Dry deposition
                                            7-13

-------
EXTERNAL DOSE FROM DEPOSITED MATERIALS
                    (cont'd)


 Deposition velocity


 -   0.1  cm/s for participate materials


 -   I cm/s for radioiodine


 -   Much higher if there is rain
                                             7-14

-------
     EXTERNAL DOSE FROM DEPOSITED
                 MATERIALS
                    (cont'd)


DCF for deposited materials is the effective dose
equivalent (EDE) in rem per:

-  I uCi/cm3 concentration of a radionuclide

-  I hour of deposition


-  96 hours of exposure to decaying radionuclides
                                              7-15

-------
       TABLE 5-5:  DCF EQUATION
           FOR GROUND SHINE
            (pp. 5-34 and 5-37)
   DCF = V  • DRCF
          g
1.14E-3
                              1-e
             -xt
DCF = the dose per unit air concentration
      (rem per uCi • cm"3 • h)
                                        7-16

-------
         TABLE 5-5: DCF EQUATION
                     (cont'd)

Vg    = deposition velocity (cm/h)

DRCF    = the dose rate conversion factor from
           DOE/EH 0070 (mrem/y per uCi/m2)

I. I4E-3   = conversion factor from mrem/y per uCi/m2
to rem/h per uCi/cm2

A        = decay constant (h"1)

t         = duration (h), assumed to be 96 hours
                                                7-17

-------
Table 5-5:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for a 4-Day Exposure to Gamma Radiation from
           Deposited Radionuclides

                      DCF                       DRL
Radionuclide          rem per                uCi • cm"3 • h
                  uCi • cm"3 • h
 H-3                 O.OE+00
 C-14                O.OE+00
 Na-22               8.3E+03                  I.2E-04
 Na-24               3.IE+03                  3.2E-04
 P-32                O.OE+00

PAG Manual - beginning on page 5-37.
                                                             7-18

-------
  MOD FY NG DOSE CONVERS ON FACTORS
Changes in physical characteristics




Changes in chemical characteristics




Changes in breathing rates




Changes in assumed deposition velocities
                                               7-19

-------
            COMBINED PATHWAYS
                (PAG Manual, Table 5-1)

The DCF and DHL for each pathway is related to the
time integrated air concentration (Xjn). They may be
combined for a particular radionuclide

DoseTotal = DoseExt+ Doselnh  + DoseGround Shine
                  • Y -4- nrp  • Y
                   Ajn T L/V^li^k  A;
            + DCFGS  • Xin
DoseTotal = Xin • (DCF^ DCFinh + DCFGS)
         = X- • DCF,
"in  fc-'^-'1 combined
                                                7-20

-------
Table 5-1:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for Combined Exposure Pathways During the Early
           Phase of a Nuclear Incident

                       DCF                        DRL
Radionuclide          rem per                uCi • cm"3 • h
                  uCi •  cm"3 • h
H-3
C-14
Na-22
Na-24
P-32
7.7E+OI
2.5E+03
1 .9E+04
7.3E+03
1 .9E+04
I.3E-02
4.0E-04
5.3E-05
1 .4E-04
5.4E-05
PAG M nual - b ginning on p g 5-9.

                                                             7-21

-------
      EXAMPLE OF COMBINED PATHWAYS
Nuclide selected

Pathway
External
Inhalation
Ground Shine
Table
5-3
5-4
5-5
Summation
DCF
(rem per uCi • cm " 3 • h)




xln
(uCi • cm"3 • h)
1
1
1

Dose
(rem)

1



Combined
5-1

1

                                         7-22

-------
        SESSION 8
DOSE PROJECTION PROBLEMS
   FOR THE EARLY PHASE

-------
              INTRODUCTION
Two student problems
   Use of combined pathways DCFs
    I a- 1 Thyroid dose at I  mile
    Ib-l TEDEat I mile
    la-2  Thyroid dose at 2 miles
    I b-2 TEDE at 2 miles
2.  Use of separate pathway DCFs
                                         8-1

-------
    STEPS TO DETERMINE THE REQUESTED
              PROJECTED DOSES

Determine diffusion coefficients (Xu/Q) at the distances
required.

Determine the wind speed in m/s (0).

Determine the source term in Ci/s (Q).

Solve for X.
                                             8-2

-------
     STEPS TO DETERMINE THE REQUESTED
              PROJECTED DOSES
                     (cont'd)

Determine the projected exposure time (Tp).


Calculate the time integrated concentration (Xjn).

Select the specific DCF (rem per pCi • cm"3 • h).

Calculate the projected dose (rem).
                                              8-3

-------
           PROBLEM  : PROJECTED DOSE
         US NG COMB NED PATHWAY DCFs

Problem la: Determine the Committed Dose Equivalent
           (CDE) to the thyroid from a plume containing
           l-!3l,and

Problem I b: Determine the Total Effective Dose Equivalent
           (TEDE) for a plume with a mix of three
           isotopes (Xe-133, I-131, and Cs-134).

And:          Determine the above doses at I  mile and 2
              miles from the release  point
                                                8-4

-------
                   PROBLEM I
Calculate at I mile
  -  Concentrations (X)




  -  Time Integrated Concentration (Xin)




  -  Dose (CDE to Thyroid and TEDE)




Use Worksheet (VG 8-6)
                                               8-5

-------
RAD AT ON ACC DENT ASSESSMENT COURSE
            WORK SHEET















Nuclide(s)
& Prblm.
# la-l

1-131


Nuclide
# Ib-l
Xe-133
1-131
Cs-134



Xu/Q
@ 1 mi
(m*2)












Q
(Ci/s)












0
(m/s)












X
@ 1 mi
(pCi/cm3)











\ r
Exp.
time
(h)











— t ,
xin
(a) 1 mi
(jjCi • cm'3* h)
...


•








DCF
Table
No.












DCF^
rem
jjCi • cm"3- h





DCFcp



TOTAL -


Dose
(CDE)
(rem)




TEDE
(rem)




8-6

-------
         PROBLEM I  INITIAL CONDITIONS
• Time from shutdown to release. 2 hours
  Estimated release time: 3 hours
  Release height: Ground level




  Stability is class D.




  Wind speed is 2 m/s (4.5 mph).




  Forecast is for no change.
                                                 8-7

-------
I
m
Xu/Q AS A FUNCTION OF
DOWNWIND DISTANCE AND
STABILITY CLASS
Values of XQ/Q (m'2)
Di tance
(Mle )
0.5
1
2
3
4
5
7
10
15
Class
A
6.6E-6
1 .OE-6
5.5E-7
3.9E-7
3.0E-7
2.5E-7
1 .9E-7
1 .4E-7
9.9E-8
Class
B
3.0E-5
7.4E-6
I.9E-6
8.4E-7
4.8E-7
3.3E-7
2.5E-7
1 .8E-7
I.3E-7
Class
C
7.6E-5
2. 1 E-5
6. 1 E-6
2.9E-6
1 .7E-6
1 .2E-6
6.3 E-7
3.3E-7
1 .8E-7
Class
D
2. 1 E-4
7.0E-5
2.4E-5
I.3E-5
8.5E-6
6. 1 E-6
3.7E-6
2.3E-6
1 .2E-6
Class
E
4.2E-4
1 .4E-4
5.0E-5
2.8E-5
1 .9E-5
1 .4E-5
8.4E-6
5. 1 E-6
3.1 E-6
Class
F
9.6E-4
3.3E-4
1.2 -4
6.8E-5
4.6 -5
3.3 -5
2.2E-5
1 .4E-5
8.4E-6
A 1250 meter lid is used.
This ' a ground level release.
8-8


-------
        PROBLEM I:  SOURCE TERM
SOURCE TERM (Q):




  - Xe-133         l,700Ci/s
  - 1-131          0.17 Ci/s
  - Cs-134         0.05 Ci/s
                                         8-9

-------
                  PROBLEM I a-1
       CALCULATE AIR CONCENTRATION (X)

• At I  mile and for I-131:

           XQ/Q = 7.0E-05 (from VG 8-8)

• WHERE:
     X = air concentration (uCi/cm3)
     U = average wind speed (m/s)
     Q = source term (Ci/s)

• SOLVE FOR X AT I MILE:
                                            8-10

-------
        PROBLEM I a-1: CALCULATE
   INTEGRATED AIR CONCENTRATION (Xin)
                FOR 1-131
Using values recorded on the Work Sheet
Solve for Xin:
                Xin = X -1
                                        8-11

-------
                  PROBLEM I a-1
       COMMITTED DOSE EQUIVALENT (CDE)
                TO THE THYROID
  The committed dose equivalent (CDE) to the
   thyroid is:

  	 (Xin • DCFth)
• The dose model is:
      ^ = DCF, • X. = DCFk
      th       th   in       th
Q
17
Xw
~Q
h
                                             8-12

-------
         PROBLEM I b-1:  PROJECTED DOSE




Calculate the TEDE for three nuclides:

  Xe-133,1-131, and Cs-134.
Assumptions: Same as for problem  I a-1
Dose Model:
TEDE = DCF  • X
            cp    in
                        = DCF
                             cp
Q .
u
XJ
Q
h
                                             8-13

-------
                 PROBLEM Ib-l
             SOLVE FOR X AT I MILE
              FOR THREE NUCLIDES
Model:
  X =
Q
    Q
           u
                  Calculate concentrations (X)
Xe-133,  Q
 /-131,  Q
C*-134,  Q
I.IE+3
\.1E-1
5.QE-2
                                      7.0£-5 =
  Q = 2 m/s
                                            8-14

-------
                 PROBLEM Ib-l
     INTEGRATED AIR CONCENTRATION (Xln)
Using the results from VG 8-14
Solve for Xjn for the three nuclides.
Exposure duration = 3 hours
                                             8-15

-------
                  PROBLEM la-2

      SOLVE FOR (CDE) TO THE THYROID FROM

                  1-131 AT 2 MILES
     L
     th
                           ^ • X.
                           th   in
•  Step I.  Obtain XQ/Q for 2 mi = 2.4E-5. (VG 8-8)
  Step 2.
2.5E-5 m'2 • \.lE-\Cils


        1 mis
                                             8-16

-------
                  PROBLEM la-2
SOLVE FOR THE (CDE) TO THE THYROID FROM I-131 AT
                     2 MILES

•  Step 3. Xin = X • h =

•  Step 4. Obtain DCFth.  The Table is	.__
     The value is
•  Step 5. Dose = Xin  • DCF^ = _
  Use the Worksheet on VG 8-18
                                             8-17

-------
       RAD AT ON ACC DENT ASSESSMENT COURSE
                      WORK SHEET

Problem I a-2 & I b-2 : Projected Dose at 2  Mile(s): From thyroid & combined  pathway
Nuclide(s)
& Prblm.
# la-2
1-131


Nuclides
# lb-2
Xe-133
1-131
Cs-134

Xu/Q
@2 mi
(m"2)









Q
(Ci/s)









Q
(m/s)









X
@_2j™
(pCi/cm3)









Exp.
time
(h)









xin
@^mi
(\iC\ • cm"3 • h)









DCF
Table
No.









DCF^
rem
jjCi • cm"3- h




DCFcp



TOTAL -
Dose
(CDE )
(rem)



TEDE
(rem)




                                                      8-18

-------
          PROBLEM  b-2: DOSE PROJECT ON
                  TEDE AT 2 M LES

Using the same assumptions for the three radionuclides,
calculate the TEDE at 2 miles.

-  Exposure duration  = 3 hours

-  Stability class = D

-  Wind speed = 2 m/s

CDEcp - DCFcp •  Xin =  DCFcp - (Q/u • XG/Q • h)
                                                 8-19

-------
         PROBLEM lb-2: FIND TEDE AT 2 MILES
             FOR Xe-133,1-131, AND Cs-134
   Step I
      X,  .
       2mi
     fi
Q
= 2AE-5
1.7E+3
1.7E-1
5.QE-2
•*• 2
• Step 2- X-h = Xin  (h = 3)

•   Step 3 - Xin • DCFcp = TEDE
          comes from Table
                                               8-20

-------
PROBLEM 2: DOSE PROJECTION USING
   SEPARATE PATHWAY DCFs

1 Assumptions:

   -  Time from shutdown to release:  2 hours

   -  Estimated release time: 3 hours

   -  Release height: Ground level

 - Stability is class D

   -  Wind speed is 2 m/s (4.5 mph).

                                                  8-21

-------
PROBLEM 2:  PROJECTED DOSE AS A FUNCTION OF
            PATHWAY
  Same source terms, meteorology, and exposure time as for
  problem I.
  Same integrated air concentrations.
  Three separate exposure pathways.
                                                 8-22

-------
PROBLEM 2:  PROJECTED DOSE AS A FUNCTION OF
            PATHWAY (cont'd)
  External dose (EDE) from the plume
   (Table 5-3)

  Plume inhalation dose (CEDE)
   (Table 5-4)

  External dose (EDE) from deposited radionuclides (Table 5-5)
                                                  8-23

-------
                PROBLEM!: DOSE MODELS
 Dose   =  DCF  •  X   = DCF
      P        p    in        p
Q.
u
Xu
Q
•  (Xu/Q • Q/u) • h = X •  h = Xin




• For I-131: (2.4E-5) • (IJE-1 )/2 = 2.0E-6 Ci/m:



• 2.0E-6 Ci/m3 • 3h = 6.0E-6 (jjCi • cm'3 • h)
  Calculate Xin and dose for each nuclide.
• Fill in matrixes (VG 8-25, 26, and 27).
h
                                                     8-24

-------
        RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                        WORK SHEET
Problem  2a :  Projected Dose at 2 Miie(s): From immersion pathway
Nuclide(s)
& Prblm.
#2a

Xe-133
1-131
Cs-134






XQ/Q
@ 2 mi
(m-2)









Q
(Ci/s)









u
(m/s)









X
@J,mi
(MCi/cm3)









Exp.
time
(h)









xin
@_2_mi
(pCi • cm'3 • h)









DCF
Table
No.









DCF^
rem
\iC\ - cm"3- h



TOTAL -





Dose
( }
(rem)









                                                        8-25

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORK SHEET
Problem  2b  : Projected Dose at 2 Mile(s): From inhalation  pathway
Nuclide(s)
& Prblm.
#2b
Xe-133
1-131
Cs- 1 34






XO/Q
@2mi
(m-2)









Q
(0/3)









u
(mis)









X
@2 mi
(pCi/cm3)









Exp.
time
(h)









x,n
@ 2 mi
(jjCi • cm'3 • h)









DCF
Table
No.









DCFM
rem
pCi • cm"3- h



TOTAL -





Dose
( )
(rem)









                                                        8-26

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORK SHEET
Problem 2c : Projected Dose at 2 Mlle(s): From deposition   pathway
Nuclide(s)
& Prblm.
#_Jc_
Xe-133
1-13!
Cs- 1 34






XQ/Q
@J_mi
(m-2)









Q
(Ci/s)









u
(mis)









X
(§U_mi
(MCi/cm3)









Exp.
time
(h)









xin
@2mi
(pCi • cm"3- h)









DCF
Table
No.









DCF^
rem
|jCi • cm"3- h



TOTAL -





Dose
< 	 >
(rem)









                                                        8-27

-------
          RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                         WORK SHEET
Problem #	2
The dose model is: Dose =  DCF •  Xin = DCF • (Q/u • XQ/Q • h)
DOSE PROJECTION AT 2 MILES FOR INDIVIDUAL PATHWAYS
Nuclide
1-131
Cs- 1 34
Xe-133
Pathway
immersion
inhalation
deposition
DCF
rem
(|jCi • cm"1 • h)
2.2E+2
3.9E+4
I.3E+4
xin
(pCi • cm'3 • h)
6.0E-6
6.0E-6
6.0E-6
Dose
(rem)
I.3E-3
2.4E-I
8.0E-2
TEDE for 1-13 1 3.2E-I
immersion
inhalation
deposition
9.IE+2
5.6E+4
6.2E+3
I.8E-6
I.8E-6
I.8E-6
I.7E-3
I.OE-1
I.IE-2
TEDE for Cs- 134 1.1 E-i
immersion
inhalation
deposition
20
0
0
6.0E-2
6.0E-2
6.0E-2
1.2
0
0
TEDE for Xe-133 1.2
TEDE for all rad ion ucl ides combined
1.5

-------
            SESSION 9

  PROTECTIVE ACTION GUIDES FOR
    RELOCATION AND RETURN

              AND

DOSE LIMITS FOR RECOVERY WORKERS

-------
                  THE "R" WORDS
                       (p. A-3)

•  Relocation: The removal or continued exclusion of
   people (households) from contaminated areas to avoid
   chronic radiation exposure.

•  Return:  The reoccupation of areas cleared for
   unrestricted residence or use.

•  Restricted zone: An area with controlled access from
   which the population has been relocated.
                                                   9-1

-------
               THE "R" WORDS
                    (p. A-3)
                     (cont'd)

Reentry:  Temporary entry into a restricted zone
under controlled conditions.

Recovery: The process of reducing radiation exposure
rates and concentrations in the environment to
acceptable levels for unconditional occupancy or use.
                                                 9-2

-------
           POTENTIAL TIME FRAME OF
       RESPONSE TO A NUCLEAR INCIDENT
  Refer to PAG Manual Page 7-5,
• Times are estimates only.
• Sequences may vary some.
                                            9-3

-------
            EXPOSURE PATHWAYS
                    (p. 4-2)

Pathways to be evaluated as basis for relocation
-  Whole body exposure to gamma radiation
-  Inhalation of resuspended materials

Minor pathways (no evaluation needed for reactor
accidents)
-  Beta skin exposure
-  Inadvertent ingestion of dirt
-  Refer to EPA 520/1-89-016
                                                9-4

-------
             ESTIMATED DOSE FROM MINOR
                  EXPOSURE PATHWAYS
Individual3
adult
child
adult or child
Exposure
Pathway
skinb
ingestionc
skin"
ingestionc
groundshine
First Year Dose (rem)
Soil
2.4
0.01
8.1
0.05
1.0
Pavement
8.4
O.I
14
0.5
1.0
aMaximum exposed individuals. Average exposure is about 1/3 to 1/6 lower.

blncludes beta dose from nearby surfaces and from material on the skin.

clnadvertent ing stion of cont mi at d dirt.
                                                             9-5

-------
        RELOCATION AND RETURN PAGS
                      (p. 4-4)
Projected Dose From
First Year Exposure

>2 rem TEDE
> 100 rem DE skin
<2 rem TEDE
< 100 rem DE
      Protective Action

Establish restricted zone and
relocate the general
population.

Apply simple dose reduction
techniques to skin.
                                                9-6

-------
        RELOCATION AND RETURN PAGS
              (p. 4-4, 4-5, E-I3,&E-20)
                      (cont'd)

Additional guidance

-  0.5 rem in any year after the first
-  5 rem in 50 years

Actual dose should be less than projected dose

   Shielding
-  Mobility
-  Special dose reduction efforts
-  Refer to tabl  s on p ges E-13 and E-20
                                                   9-7

-------
                 ARBITRARY SCALE
                                                         PLUME TRAVEL
                                                           DIRECTION
LEGEND
         1.  PUIME DEPOSITKNI



         2.  AREA FROM WHICH POPULATION « EVACUATED.


         3.  AREA IN  mtKM POPULATION IS 9NBL1BREO.
                  FROM WHICH     LAtnON « RELOCATED (BCSTWCTED ZONE).
                                                                                       9-8

-------
               GRADUAL RETURN
                   (p. 4-5 & 7-4)

Establishment of buffer zone

Gradual return

FEMA option to combine temporary relocation and gradual
return boundaries

-  Advantage - no early dose calculations

   Disadvantage - large relocation area
                - major public disruption
                                                  9-9


-------
       DOSE REDUCTION FOR RETURNEES
                    (p. 4-3)
Areas for priority

-  Dose in excess of 0.5 rem in I st year

-  Residences of pregnant women

Responsibility for actions
                                                9-10

-------
                  EXAMPLES OF
     S MPLE DOSE REDUCT ON TECHN QUES
             (pp.4-3, 7-6, E-I3.&E-I9)

Scrub/flush/wipe hard surfaces.

Soak or plow soil.

Cut and remove grass clippings and other foliage.

Remove spots of soil where radioactivity has concentrated.

Disposal of contaminated materials
                                                 9-11

-------
     SIMPLE DOSE REDUCTION TECHNIQUES
             (pp. 4-3, 7-6, E-I3,&E-I9)
                     (cont'd)

Remove debris.

Spend more time in areas with lower contamination levels
(e.g., indoors).

Replace sandbox sand.

Pay special attention to child hygiene.
                                                 9-12

-------
      RAT ONALE - FOUR PR NC PLES
Acute health effects
Delayed health effects




Cost of avoiding risk




Risk - risk comparison
                                               9-13

-------
         FACTORS NOT NGLUDED N
            THE RELOCAT ON PAGs
Physical and mental stress

Past exposures

Dose from ingestion

Dose from occupational exposure
                                              9-14

-------
                 COST ANALYSIS
                (pp. E-8, E-9, & E-10)
Assumptions:
-  Value of avoiding a statistical death is $400,000 to
   $7,000,000.

-  Average daily cost of relocation is $27 - Refer to EPA
   520/1-89-015.

Where does the daily cost of relocation equal the
monetary value of average daily risk avoided?
                                                    9-15

-------
                                                        - 0.2
I        I        10        II        10       II        3(
                TIM! AfTIM ACCIOINT (tf«y*>

FIQU    6-3. COSt OF AVOIDING STATISTICAL FATALITIES  AND
            EXPOSURE  RATES CORRESPONDING TO  VARIOUS
            TOTAL FIRST  YEAR DOSES (ASSUMES AN SST-2
            ACCIDENT AND A $27 PER PERSON-DAY  COST OF
            RELOCATION).
                          I-10
                                                          9-16

-------
          PRINCIPLE
BASIS FOR SETTING PAG LEVELS
              (p. I -5)

                       STRATEGY
(I)  Avoid acute health effects.

(2)  Adequately protect against
    cancer and genetic effects
    under emergency conditions.
(3)  Optimize cost of protective
    action versus avoided dose.

(4)  Regardless of the above
    principles, the risk from a
    protective action should not
    itself exceed the risk from the
    dose that would be avoided.
                      Stay below threshold dose.

                      Set PAG at this level unless
                      driven down by cost/risk
                      considerations (3), or up by
                      risk/risk considerations (4).

                      Use this principle only if the
                      the PAG value is driven down.

                      Use this principle only if the
                      PAG value is driven up.
                                                                           9-17

-------
   CONCLUSIONS ON APPROPRIATE VALUE
            FOR RELOCATION PAG
                   (p.E-18)

Principle on acute effects is not applicable.

judgment of acceptable level of risk of delayed health
effects:
-  5 rem in 50 years
-  0.5 rem in any single year after the first

2 rem in the first year will meet the above criteria for
nuclear  power plant accidents.
                                               9-18

-------
   CONCLUSIONS ON APPROPRIATE VALUE
           FOR RELOCATION PAG
                  (p. E-18)
                    (cont'd)

Cost will not drive the first year dose below 2 rem.
Risk from relocation is assumed to be the same as for
evacuation (i.e., equivalent to the risk from about 30
mrem).
                                             9-19

-------
   DOSE LIMITS FOR RECOVERY WORKERS
            (pp.46, 7 17, &E 19)

Same as for occupationally exposed workers

-  TEDE                         5 rem/y
-  CDE to any organ               50 rem/y

-  One tenth these values to persons under
   age 18

-  TEDE to declared pregnant
   women                       0.5 rem/9mo
                                           9-20

-------
              SESSION 10
DATA COLLECTION AND DOSE PROJECTION
                FOR
  RELOCATION AND RETURN DECISIONS


-------
IMPLEMENTING PAGS FOR THE INTERMEDIATE
                  PHASE

Relocation

Reentry

Return

Early Decontamination

Ingestion of Food and Water
-   Independent decision
                                           10-1

-------
                  OVERV EW OF
            MPLEMENTAT ON PROCESS

•  Collect environmental samples.

•  Analyze samples.

•  Calculate
   -   Exposure rates and projected dose.
   -   Accident specific DCFs.
   -   Derived response level.

•  Make gamma exposure rate measurements.
                                               10-2

-------
                OVERV EW OF
           MPLEMENTAT ON PROCESS
                     (cont'd)

Take air samples and calculate projected dose from
inhalation of resuspended materials.

Identify the boundary of the restricted zone.

Relocate the population.

Identify the buffer zones.

Implement gradual return.
                                                10-3

-------
     SAMPLE COLLECT ON AND ANALYS S

Purpose of samp es
-  Dose projection
-  Evaluation of variation in mix by area

Nature of samples

Locations of samples
-  Based on exposure rate
-  Priorities
-  Terrain

Types of analyses
                                                10-4

-------
          ALTERNATIVE METHODS
           FOR DOSE PROJECTION

METHOD ONE - Sample from each area of interest

-   Known size of area in each sample

-   Use data from each sample analysis to project dose.

-   Plot projected doses on map to identify location of
   boundary to the restricted zone.
                                             10-5

-------
        ALTERNATIVE METHODS FOR
             DOSE PROJECTION
                    (cont'd)

METHOD TWO - Take a few samples from several
areas.

Determine whether the radionuclide mix is reasonably
constant or predictable. If so:

-  Calculate a time-dependent derived response level
          corresponding to the PAG.
   Use the DRL^ to identify the restricted zone.
                                              10-6

-------
     CONS DERAT ON OF METHOD ONE

Requires a arge number of
-  samples
-  laboratory analyses
-  dose projections

May yield wrong result for other than flat terrain

Only method available if radionuclide mix is neither
constant nor predictable
                                               10-7

-------
        CONSIDERATION OF METHOD TWO
•  Not useful for an inconsistent mix of radionuclides.

•  Greatly reduces the sampling and laboratory effort.

•  Results are independent of terrain type or presence of
   contaminated foliage.

•  Inaccuracies due to non-representative samples cancel.
                                                   10-8

-------
EXAMPLE CALCULATION OF EXPOSURE RATE
            - Method One -
Radionuclide
Cs- 1 34
1-131
Concentration
pCi/m2
2E+7
3E+7
Initial exposure Rate @ 1 nrt
(mR/h per pCi/m2)
(table 7-1 or 7-2)
.

Total:
Exposure Rate @ 1 m
(mR/h)

•

                                    10-9

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Year One
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)


TOTAL
Projected
Dose
(mrem)



                                     10-10

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Year Two
Radionuclide
Cs- 1 34
1-131
Concentration(
pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
(mrem/pCi/m2)
. (Table 7-2)

•
TOTAL
Projected
Dose
(mrem)
.


                                        10-11

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Zero to 50 Years
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
. (mrem/pCi/m2)
(Table 7-2)


TOTAL
Projected
Dose
(mrem)



                                       10-12

-------
                  METHOD 2
Calculate an accident-specific dose conversion factor
(DCFJ.

-  This factor is time dependent.
Use DCFas to calculate a time-dependent derived
response level (DRL^) in mR/h corresponding to the
PAG.
                                               10-13

-------
 CALCULAT ON OF ACCIDENT SPEC F C DCF
                  Method 2
    mrem Per
                          ~2» °r 0 to 50 yr
35
              Exposure Rate @ I m (mRIti)
Assume weathering and results from VGs 9, 10, II,
and 12, and calculate:

-  Year one DCF^ =
   Year two DCF,C =
               as
   Zero to 50 year DCFas =
                                           10-14

-------
 CALCULATION OF ACCIDENT SPECIFIC DRL
                 Method 2
               DRL
                   td
 PAG
DCF
                          as
For the previous example (weathering included):
  Year one DRLas =
   Year two DRLas =
   Zero to 50 year DRLas =
                                          10-15

-------
  DCF FOR PROJECTED  EXTERNAL GAMMA DOSE
DCF = DSf  t*   *      dt

             0


     63|l -e ~("" + * }     37(l -e
     '*T «   '
    DCF = DSf


               '1




= dose rate per unit deposit (mrem/yr per pCi/m2) (data in DOE EH 0070)



Sf   = protection factor for shielding and partial occupancy (assumed to be unity)



AR   = radioactive decay constant (yr"1)



A2   = assumed weathering decay constant for 63% of the radionuclide =1.13 yr '




A3   = assumed weathering decay constant for 37% of the radionuclide = 7.48E-3 yr"1



t   = time of exposure (yr)
                                                                  10-16

-------
    CALCULATION OF DOSE FROM INHALATION
        OF RESUSPENDED MATERIALS (CEDE)
                 (Table 7-4, p. 7-16)

                   Hso = I x DCF
WHERE:
   Hso = CEDE for 50 y from intake of nuclides

   I   = total intake (pCi)

   DCF  =  dose per unit intake for the radionuclide
           (rem per pCi)
           -   Data are from EPA FGR No. I I
           -   Convert to appropriate units
                                               10-17

-------
            TOTAL INTAKE FROM  INHALATION
                 OF RESUSPENDED MATERIAL
           '-—«
WHERE:

I    =   total intake in I year (pCi)

B   =   breathing rate, assumed to be I.05E+4 mVyr

C0  =   initial air concentration of the resuspended radionuclide (pCi/m3)

AR  =   radioactive decay constant (yr'1)

A2  =   assumed weathering decay constant for 63% of the radionuclide =1.13 yr"1

A3  =   assumed weathering decay constant for 37% of the radionuclide = 7.48E-3 yr"1

t   =   time of exposure (yr)

                                                                    10-18

-------
    WEATHERING OF THE RESUSPENSION FACTOR

•  EPA assumes gamma weathering for resuspension.

•  Empirical data for alpha emitters shows much faster
   reduction.

•  Refer to:
   -  WASH-1400 Appendix VI page E-13 for a time
      dependent model.

   -  IAEA Safety Series 81,1986, page 62 for plot of the
      resuspension factor as a function of time and of the
      integral.
                                                 10-19

-------
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ ] yes [ ] no
Sample
Radio-
Nuclide
Cs-134
1-131




location Analysis date

Air
Concentration
(pCi/m3)
1200
420




Yr. 1 DCF
(mrem per
pCi/m3)





TOTAL-
Dose From
Yr. 1 Exp.
(mrem)






Yr. 2 DCF
(mrem per
pCi/m3)





TOTAL-
Dose From
Yr. 2 Exp.
(mrem)






10-20

-------
           SESS ON
    DOSE PROJECTION PROBLEMS
              FOR
RELOCATION AND RETURN DECISIONS

-------
        PROBLEM I - A:  DERIVATION OF AN
            ACCIDENT-SPECIFIC DOSE
            CONVERSION FACTOR (I)
                 -Method ONE-
GIVEN:
•  A surface soil sample is analyzed and is found to
   contain the following concentrations (pCi / m2):

     Zr-95    7.4 E+6       Cs-134  I2.0E+6
     Ru-103   3.1 E+6       Cs-137  1.2 E+6
     1-131     4.1 E+6       Ba-140  6.2 E+6

•  Radioactive decay and weathering will occur.
                                               11-1

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ x] Year 1 [ ] Year 2 [ ] 50 Years
t
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs- 1 34
Cs- 1 37
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3.IE+06
4. 1 E+06
1 .2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
PCi/m2)






TOTAL-
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

.




TOTAL-
Calculated
DOSE
(mrem)







Combined DCF,
mrem per mR/h
(date_
                                        11-2

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ X] Year 2 [ ] 50 Years
»
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3.IE+06
4. 1 E+06
1.2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

t




TOTAL-
Calculated
DOSE
(mrem)


•




Combin d DCF
            as
mr m per mR/h
(dt
                                                               11-3

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ ] Year 2 [ X] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs- 1 34
Cs- 1 37
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3.IE+06
4. 1 E+06
1 .2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Calculated
Exp, Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

f




TOTAL-
Calculated
DOSE
(mrem )







Combin d DCF
             as
mr m p r mR/h
(dat
                                                                    11-4

-------
        PROBLEM I  - B:  DERIVATION OF AN
            ACCIDENT-SPECIFIC DOSE
            CONVERSION FACTOR (I)
                 -  Method TWO -
GIVEN:
•  A surface soil sample is analyzed and is found to
   contain the following activities (uCi / sample):

     Zr-95    7.4         Cs-134  12
     Ru-103   3.1         Cs-137  1.2
     1-131     4.1         Ba-140   6.2

•  Radioactive decay and weathering will occur.
                                               11-5

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ x] Year 1 [ ] Year 2 [ ] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3. 1 E+06
4. 1 E+06
1 .2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pG/m2)






TOTAL-*
Nominal
Calculated
Exp. Rate
(mR/h@lm)







Integrated
Dose
(mrem per
pCi/m2)

•




TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)


.




Combined DCF
             as
mrem per mR/h
(date_
                                                                     11-6

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ X] Year 2 [ ] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs- 1 37
Ba-140

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3. 1 E+06
4. 1 E+06
I.2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

.




TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)







Combined DCF
             as
mrem per mR/h
(date_
                                                                        11-7

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ ] Year 2 [ X] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3.IE+06
4.IE+06
1 .2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)






TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)


•




Combined DCF,
mrem per mR/h
(date_
                                         11-8

-------
     PROBLEM 2: DERIVED RESPONSE LEVELS

Using results from Problem I, calculate time-dependent
derived response levels (DRL^) corresponding to:

-  year I

-  year 2

-  50 years
Interpret the results.
                                                 11-9

-------
                   PROBLEM 3
                PROJECTED DOSE

Field teams report the following exposure rates:
   Location A       3 mR/h
   LocationB       10 mR/h
   Location C      30 mR/h

Assume the radionuclide mix from Problem I.

What is the projected dose from gamma radiation at each
location for each of the three time periods?
                                                 11-10

-------
                               V
                        SESSION  12
          COURSE REVIEW AND WRAP-UP
Ritchey C. Lyman
Office of Radiation and Indoor Air
Phone (202) 564-9363
Fax: (202) 565-2037
lyman.ritchey@epa.gov

-------
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
Sample location A Analysis date
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs- 1 34
Cs- 1 37
Ba-140


Air
Concentration
(pCi/m3)
760
320
420
1200
120
630


Yr. 1 DCF
(mrem per
pCi/m3)







TOTAL-
Dose From
Yr. 1 Exp.
(mrem)








Yr. 2 DCF
(mrem per
pCi/m3)







TOTAL-
Dose From
Yr. 2 Exp.
(mrem)


.





11-13

-------
- PROBLEM SOLUTIONS -

-------
                          PROBLEM SOLUTION
Problem Emergency worker   : Projected Dose at Location A from inhalation

Nuclide(s)
Ce-I4l
Ba-140
Cs-134


Air
Concentration
(X)
(uCi/cm3)
I.OE-05
I.OE-04
I.OE-05


Projected.
Exposure
Time
(h)
1
1
1


Integrated Air
Concentration
(uCi • cm"3 • h)
0.00001
0.0001
0.00001


DCF from
Table 5-4
(rem per
uCi • cm"3 • h)
I.IE+04
4.5E+03
5.6E+04
Totals >
Inhalation
Committed
Effective Dose
Equivalent
(CEDE)
(rem)
0.11
0.45
0.56
1.12
                                                                       6-22a

-------
      EXAMPLE OF COMBINED PATHWAYS
                 SOLUTION

Nuclide selected Co-60

Pathway
External
Inhalation
Ground Shine
Table
5-3
5-4
5-5
Summation
DCF
(rem per uCi • cm " 3 • h)
I.5E+3
2.6E+5
8.9E+3

xin
(uCi ; cm"3 • h)
1
1
1

Dose
(rem)
I.5E+3
2.6E+5
8.9E+3
2.6E+5

Combined
5-1
2.7E+5
1
2.7E+5
                                        7-22a

-------
         RAD AT ON ACC DENT ASSESSMENT COURSE
                         WORK SHEET
Problem la-1 & Ib-l  : Projected Dose at I   Mile(s): From thyroid & combined pathway
Nuclide(s)
& Prblm.
# la-l
1-131


Nuclide
# Ib-l
Xe-133
1-131
Cs-134

XQ/Q
@ 1 mi
(m-2)
7.0E-5




7.0E-5
7.0E-5
7.0E-5

Q
(Ci/s)
0.17




1700
0.17
0.05

G
(m/s)
2




2
2
2

X
@J_mi
L(MCi/cm3L
6.0E-6




6.0E-2
6.0E-6
I.8E-6

Exp.
time
(h)
3




3
3
3

xin
@J_mi
(pCi • cm"3 • h)
I.8E-5




I.8E-I
I.8E-5
5.25E-5

DCF
Table
No.
5-2




5-1
5-1
5-1

DCF^
rem
pCi • cm"3- h
I.3E+6



DCFcp
2.0E+ 1
5.3E+4
6.3E+4
TOTAL -
Dose
(CDE)
(rem)
23


TEDE
(rem)
3.6
0.95
0.33
4.9
                                                              8-6a

-------
     RAD AT ON ACC DENT ASSESSMENT COURSE
                     WORK SHEET

Problem la-2 & lb-2  : Projected Dose at 2 Mile(s): From thyroid & combined pathway
Nuclide(s)
& Prblm.
# la-2
1-131


Nuclides
# lb-2
Xe-133
1-131
Cs-134

XQ/Q
@ 2 mi
(m-2)
2.4E-5




2.4E-5
2.4E-5
2.4E-5

Q
(Ci/s)
0.17




1700
0.17
0.05

Q
(m/s)
2




2
2
2

X
@ 2 mi
(pCi/cm3)
2.0E-6




2.0E-2
2.0E-6
6.0E-7

Exp
time
(h)
3




3
3
3

xin
@ 2 mi
(pCi • cm"3- h)
6.0E-6




6.0E-2
6.0E-6
I.8E-6

DCF
Table
No.
5-2




5-1
5-1
5-1

DCF*
rem
\iC\ ' cm"3* h
I.3E+6



DCFcp
2.0E+I
5.3 E+4
6.3E-J-4
TOTAL -
Dose
fCDEl
(rem)
8


TEDE
(rem)
1.2
0.32
0.12
1.6
                                                      8-18a

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORKSHEET
Problem   2a  Projected Dose at 2  Mile(s): From immersion
pathway
Nuclide(s)
& Prblm.
# 2
Xe-133
1-131
Cs- 1 34





Xu/Q
@2 mi
Cm'2)
2.4E-5
2.4E-5
2.4E-5





Q
(Ci/s)
1700
0.17
0.05





U
(m/s)
2
2
2





X
@ 2 mi
(MCi/cm3)
2.0E-2
2.0E-6
6.0E-7





Exp.
time

-------
       RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORK SHEET

Problem  2b  : Projected Dose at 2  Mile(s):  From inhalation  pathway
Nuclide(s)
& Prblm.
# 2b
Xe-133
1-131
Cs- 1 34




XQ/Q
@2 mi
(m-2)
2.4E-5
2.4E-5
2.4E-5




Q
(Ci/s)
1700
0.17
0.05




u
(m/s)
2
2
2




X
@ 2 mi
(pCi/cm3)
2.0E-2
2.0E-6
6.0E-7




Exp.
time
M
3
3
3




xin
@_Lmi
(pCi • cm"3- h)
6.0E-2
6.0E-6
1 .8E-6




DCF
Table
No.
5-4
5-4
5-4




DCFinh
rem
MCi • cm"3- h
0
3.9E+4
5.6E+4
TOTAL-



Dose
(CEDE)
(rem)
0
2.4E-I
1 .OE- !
3.4E-I



                                                          8-26a

-------
     RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                       WORK SHEET

Problem 2c :  Projected Dose at_2_Mile(s):  From ground shine pathway
Nuclide(s)
& Prblm.
# 2c
Xe-133
1-131
Cs-134




Xii/Q
@2mi
(m-2)
2.4E-5
2.4E-5
2.4E-5




Q
(Ci/s)
1700
0.17
0.05




u
(m/s)
2
2
2




X
@2mi
(nCi/cm3)
2.0E-2
2.0E-6
6.0E-7




Exp.
time
(h)
3
3
3




XiB
@2mi
(jiCi • cm'3- h)
6.0E-2
6.0E-6
1.8E-6




DCF
Table
No.
5.5
5.5
5.5




DCFdep
rem
|iCi • cm'3- h
0
1.3E+4
6.2E+3
TOTAL -



Dose
(EDE)
(rem)
0
8.0E-2
UE-2
0.09



                                                          8-27a

-------
EXAMPLE CALCULATION OF EXPOSURE RATE
             - Method One -

              SOLUTION
Radionuclide
Cs-134
1-131
Concentration
pCi/m2
2E+7
3E+7
Initial exposure Rate @ 1m
(mR/h per pCi/m2)
(table 7-1 or 7-2)
2.6E-8
6.6E-9
Total:
Exposure Rate @ 1m
(mR/h)
0.52
0.20
0.72
                                                10-9a

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             -M thodOn -

              SOLUTION
Integrated Dose - Year One
Radionuclide
Cs-134
M31
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
l.OE-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
2000
39
2039
No Weathering
DCF
(mrem/pCi/m2)
(table 7-2)
1.3E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
2600
39
2639
                                     10-10a

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
              - Method One -
               SOLUTION
Integrated Dose - Year Two
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
4.7E-5
0
TOTAL
Projected
Dose
(mrem)
940
0
940
No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)
9.6E-5
0
TOTAL
Projected
Dose
(mrem)
1900
0
1900
                                                 10-lla

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
              - Method One -
               SOLUTION
Integrated Dose - Zero to 50 Years
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
2.4E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
4800
39
4839
No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)
4.7E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
9400
39
9439
                                   10-12a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF

                  - Method 2-




                  SOLUTION
          mrem per yr-1, yr-2,  or 0 to 50 yr
          	           	__           J
              Exposure Rate @ 1 /n (mR/h)
 Assume weathering and results from VGs 9,10,11, and 12, and

    calculate:




 -   Year one DCFas = 2039 mrem/0.72 mR/h = 2832 mrem/mR/h




 -   Year two DCFas = 940 mrem/0.72 mR/h = 1305 mrem/mR/h




 -   0 to 50 y ar DCFas = 4839 mr m/0.72 mR/h = 6720



                                              10-14a

-------
     CALCULATION OF ACCIDENT SPECIFIC DRL
                     - Method 2 -

                     SOLUTION
                   DRL
      PAG
ta   DCF
                               as
For the previous example (weathering included):
- Year one DRLas = 2000 mrem + 2832 mrem/mR/h = 0.71 mR/h

- Year two DRLas = 500 mrem -5-1305 mrem/mR/h = 0.38 mR/h

- Zero to 50 year DRLas = 5000 -s- 6720 = 0.74 mR/h
                                                   10-15a

-------


CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
Sample
Radio-
Nuclide
Cs-134
1-131




location Analysis date

Air
Concentration
(pCi/m3)
1200
420




Yr. 1 DCF
(mrem per
pCi/m3)
3.1E-1
1.1E-2



TOTAL-
Dose From
Yr. 1 Exp.
(mrem)
370
4.6



375
Yr. 2 DCF
(mrem per
pCi/m3)
1.5E-1
0



TOTAL-
Dose From
Yr. 2 Exp.
(mrem)
180
0



180

10-20 a

-------
  Problem 1: Derivation of an Accid  nt-Sp cific Dose Conv rsion Factor

                           SOLUTION

•  Refer to Table 7-1 and, as example, Table 7-3.

•  Unit of the DCF for the projected external gamma dose is:
     xx mrem for each mR/h measured at the beginning of the period

•  For year one:
                1.6E+03 mrem per 4.9E-01 mR/h yields
             3.3e+3 mrem per mR/h or 3.3 rem per mR/h

•  For 0-50 years:
                   4.0E-03 mrem per 4.9E-01 mR/h
             8.2E+3 mrem per mR/h or 8.2 rem per mR/h
                                                               ll-la

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [xJYearl [ ] Year 2 [ ] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

\ A Weathering*

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6c-08
l.Oe-08
3.2e-09
TOTAL-

Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.3e-05
7.1e-06
1.3e-06
l.Oe-04
4.5e-05
l.le-05
TOTAL-
Calculated
DOSE
(mrem)
2.4e+02
2.2e+01
5.3e+00
1.2e+03
5.4e+01
6.8e+01
1.6e+03
Co  bined DCFas __3.3 e+03__  re   per  R/h
(date
                                                                      ll-2a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ JYearl [x] Year 2 [ ] 50 Years
Sample locat'oi
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

n A Weather ng

Initial Exp.
Rate @ Ini
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
7 [x]yes []
Integrated
Dose
(mreni per
pCi/m2)
4.0e-07
O.Oe+00
O.Oe+00
4.7e-05
2.9e-05
O.Oe+00
TOTAL-
no
Calculated
DOSE
(mrem)
3.0e+00
O.Oe+00
O.Oe+00
5.6e+02
3.5e+01
O.Oe+00
6.0e+02
Co  binedDCFas__1.2e+03—  re  per mR/h   (date_
                                                                     ll-3a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ JYearl [ ] Year 2 [x] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
R u -103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering'

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-

Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.4e-05
7.1e-06
1.3e-06
2.4e-04
6.1e-04
l.le-05
TOTAL-
Calculated
DOSE
(mrem)
2.5e+02
2.2e+01
5.3e+00
2.9e+03
7.3e+02
6.8e+01
4.0e+03
Co  bined DCFas _8.2 e+03__mre  per   R/h
(date
                                                                  ll-4a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [x]Yearl [ ] Year 2 [ ] 50 Years
Sample locatioi
Radio-
lS u elide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering*

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.3e-05
7.1e-06
1.3e-06
l:0e-04
4.5e-05
l.le-05
TOTAL-
Nominal
Calculated
DOSE
(mrem)
2.4e+02
2.2e+01
5.3e+00
1.2e+03
5.4e+01
6.8e+01
1.6e+03
Co  bined DCFas _3.3 e+03_  re  per  R/h
(date.
                                                                       ll-6a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [
Sample locatioi
Radio-
IS uclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

Yearl [x] Year 2 [ ] 50 Years
n A Weathering

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [x]yes []
Integrated
Dose
(mrem per
pCi/m2)
4.0e-07
O.Oe+00
O.Oe+00
4.7e-05
2.9e-05
O.Oe+00
TOTAL-
no
Nominal
Calculated
DOSE
(mrem)
3.0e+00
O.Oe+00
O.Oe+00
5.6e+02
3.5e+01
O.Oe+00
6.0e+02
Combin d DCFas _1.2 e+03_ mrem p r mR/h   (d t
                                                                 ll-7a

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ lYearl [ ] Year 2 [x] 50 Years
Sample location A Weathering? I x] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
Integrated
Dose
(mrem per
pCi/m2)
3.4e-05
7.1e-06
1.3e-06
2.4e-04
6.1e-04
l.le-05
TOTAL-
Nominal
Calculated
DOSE
(mrem)
2.5e+02
2.2e+01
5.3e+00
2.9e+03
7.3e+02
6.8e+01
4.0e+03
Co  bined DCFas _8.2 e+03_  re   per  R/h
(date
                                                                    ll-8a

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                  Problem 2: Derived Respons L v Is

                             SOLUTION

A time-dependent derived response level (DRLtd) is the meter reading (mR/h @ 1m)
which, at the time of measurement, corresponds to either the year 1, year 2, or 0-50
year dose.

For year one, a meter reading of 1 mR/h at 1 meter above the ground indicates an
external gamma radiation dose of 3.3 rem during the first year.  Therefore, the
DCF (rem per mR/h) is 3.3 rem per mR/h.

A meter reading of 2.0/3.3 or about 0.6 mR/h, would indicate that the first year dose
would be 2 rem or greater.

The DRLtd for year 1 is 0.6 mR/h.

The DRLtd for year 2 is 0.5/1.2 or about 0.4 mR/h.

The DRL for ye r 0-50 is 5.0/8.2 or  bout 0.61 mR/h.
                                                                       ll-9a

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                Problem 2 Derived Response Levels
                          SOLUTION
                           (contfd)

Table 4-1: Protective Action Guides for Exposure to Deposited
Radioactivity During the Intermediate Phase of a Nuclear Incident

    Relocate if projected dose is greater than 2 rem.

    Projected dose includes external gamma radiation dose and the
    committed effective dose equivalent from inhalation during the
    first year.

    Beta skin dose may be up to 50 times higher.

Persons in areas with meter readings above 0.6 mR/h should be
relocated.

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Problem 3  Projected Dose
      SOLUTION
Location
A
B
C
Meter
Reading
(mR/hr)
3
10
30
Projected
Dose
year one
(rem)
9.9
33
99
DCF for year 1 (rem per mR/h)
DCF for year 2 (rem per mR/h)
DCF for 0 to 50 y (rem per mR/h)
Projected
Dose
year two
(rem)
3.6
12
36
3.3
1.2
8.2
Projected
Dose
0 toSOy
(rem)
24.6
82
246



                                       ll-lla

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Prob em 4: Inha ation Do e (CEDE)
         SOLUTION
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
S:
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

imple location A Analysis date

Air
Concentration
(pCi/m3)
760
320
420
1200
120
630

Yr. 1 DCF
(mrem per
pCi/m3)
6.5e-02
1.3e-02
l.le-02
3.1e-01
2.5e-01
4.4e-03
TOTAL-
Dose From
Yr. 1 Exp.
(mrem)
4.9e+01
4.2e+00
4.6e+00
3.7e+02
3.0e+01
2.8e+00
4.6e+02
Yr. 2 DCF
(mrem per
pCi/m3)
•


1.5e-01
1.4e-01

TOTAL-
Dose From
Yr. 2 Exp.
(mrem)
O.Oe+00
O.Oe+00
O.Oe+00
1.8e+02
1.7e+01
O.Oe+00
2.0e+02

-------
                Problem 4:1 h latio  Dose (CEDE)
                          SOLUTION
                            (co t'd)

•  Year one CEDE - 4.6E+02 mrem or 0.46 rem

•  Year two CEDE - 2.0E+02 mrem or 0.20 rem

•  Year one EDE - 9.9 rem (see problem 3)

•  Year one TEDE - 9.9 + 0.5 = 10.4 rem

•  Year two EDE - 3.6 rem (see problem 3)

•  Year two TEDE - 3.6 + 0.20 = 3.8 rem

•   Normally the lung clearance class and the particle size are not known.
   Assume the most conservative condition.

-------
MANUAL OF PROTECTIVE
  ACTION GUIDES AND
  PROTECTIVE ACTIONS
FOR NUCLEAR INCIDENTS
        Presented By

The Environmental Protection Agency
           at

    NASA HEADQUARTERS
          date

      JUNE 10-11, 1998

-------
          SESSION I
WELCOME AND INTRODUCTIONS

-------
                               EPA 400-R-92-001
          MANUAL OF PROTECTIVE ACTIONS AND PROTECTIVE
        ACTIONS FOR NUCLEAR INCIDENTS WORKSHOP
                              NASA HEADQUARTERS
                                300 E STREET, S.W.
                                WASINGTON D.C.
                                JUNE  10-11,  1998

Wednesday, June 10,  1998
      8:30 -   9:00 an     Welcome and Introductions
      9:00 -  10:00 am

     10:00 -  11:00 am

     11:00 -  12:00 pm


     12:00 -  1:00 pm

      1:00 -  2:30 pm


      2:30 -  4:30 pm


      4:30

Thursday, June 11,  1998

      8:30 -  10:00 am
     10:00

     11:00

     12:00

      1:00

      3:30
11:00 pm

12:00 pm

 1:00 pm

 3:30 pm

 4:00 pm
             Overview (Bow th* PAO manual ie laid out)

             Rationale for PAG values  (PAG Principles)

             Application and Interpretation of PAGs  (When to use them and
             how)

             Lunch

             Introduction to Dose Projection (Discussion of Terminology
             and EPA assumptions used)

             Implementation of Emergency Worker Dose Limits (Who are
             Emergency Workers and What limits apply)

             End of Day One
Development of DCFs and DHLs  (What are they and how do you
apply them)

Dose Projection for Early Phase  (Problem  solving)

PAGs for Relocation (Assumptions made and rationale for use)

Lunch

Dose Projection for Relocation  (Problem solving)

Review and Wrap-up

-------
            SESSION 2
OVERVIEW OF BACKGROUND MATERIALS
    SUPPORTING THE WORKSHOP

-------
                   TOPICS
Response areas
Organization and content of the PAG Manual
and its major support documents
                                 ^

Exposure pathways


Incident phases
                                              2-1

-------
2.  AREA FROM WHICH POPULATION IS
   ABEAM
                                                PLUME  TRAVEL
                                                  DIRECTION
                                  RELOCATED (RESTRICTED ZONE).
                                                                              2-2

-------
        CONTENTS OF THE PAG MANUAL
CHAPTERS            SUBJECTS

   I          Background information

2, 3, & 4    PAGs for plume, ingestion, and
             relocation

5, 6, & 7    Implementation guidance for the
             3 PAG categories

   8          Reserved for recovery guidance
                                              2-3

-------
        CONTENTS OF THE PAG MANUAL
                       (cont'd)
APPENDICES     SUBJECTS


   A       Definitions of terms


   B       Risk of health effects from radiation


   C       Rationale for selecting the early phase
           PAG values


   D       Rationale for food PAGs


   E       Rationale for Relocation PAGs

                                                2-4

-------
       MAJOR SUPPORT DOCUMENTS

Externa Dose-Rate Conversion Factors for Ca cu ation
of Dose to the Public (DOE/EH 0070)

EPA Federal Guidance Report No. 11
(EPA 520/1 -88-020)
                               (>
EPA Federal Guidance Report No. 12
(EPA402-R-93-08I)
                                             2-5

-------
     MAJOR SUPPORT DOCUMENTS (cont'd)

Evaluat'on of Sk'n and Ingest'on Exposur  P thw ys
(EPA 520/1 -89-016)

Evacuation Risks—An Evaluation
(EPA-520/6/74-002)

An Analysis of Evacuation Options for Nuclear
Accidents (EPA 520/1 -87-023)

Economic Criteria for Relocation
(EPA 520/1 -89-015)
                                               2-6

-------
        Airborne
        Plume
    Gamma Rays
                              Inhalation
                               Irigestion
                                   Beta
         Restispensicm
                                        2-7
                                   Particles
                  Deposited Paniculate Material
Exposure Pathways for the Early Phase

-------
              INCIDENT PHASES
                (pp. I -2 to I -4)

Three phases of a radiological incident
-  Early
-  Intermediate
-  Late

In all phases, the PAGs are independent

Refer to PAG Manual Page I -4.
                                               2-8

-------
          SESSION 3
  RATIONALE FOR PAG VALUES
            AND
EMERGENCY WORKER DOSE LIMITS

-------
                      TOPICS
Protective action effectiveness
PAG Principles
Basis for PAG values and Emergency worker dose limits
                                                      3-1

-------
    ttfKJSKvatKnti. .a«g3g^:rr^K:'Jvr?;rt:'r.grr.it.'i-:j^^         •:> ajj iKK^.j^.-^snfzK-sav-ir.-^,- —.

         PROTECTIVE ACTIONS
         FOR THE EARLY PHASE
                   (p. 1-4)
Evacuation
Sheltering
Access control
KI administration
Control of surface contamination
                                             3-2

-------
   BASIS FOR PROTECTIVE ACTION
DECISIONS DURING THE EARLY PHASE
               (p. 5-2)

Plant conditions and utility PARs
Dose projections
Field monitoring results
                                        3-3

-------
          SHELTERING CONSTRAINTS
          (pp. 5-19 to 21 andC-!4to 16)

Sheltering provides only partial protection.

-  Protection factor decreases with time.

-  Ventilation rates vary.

-  Protection varies with building type.

-  Risk of shelter failure is significant.
                                                  3-4

-------
                 BASIS FOR SETTING PAG LEVELS
                                 (p. 1-5)
          PRINCIPLE                     STRATEGY
(I)  Avoid acute health effects.                Stay below threshold dose.
(2)  Adequately protect against
    cancer and genetic effects
    under emergency conditions.
(3)  Optimize cost of protective
    action versus avoided dose.

(4)  Regardless of the above
    principles, the risk from a
    protective action should not
    itself exceed the risk from the
    dose that would be avoided.
Set PAG at this level unless
driven down by cost/risk
considerations (3), or up by
risk/risk considerations (4).

Use this principle only if the
the PAG value is driven down.

Use this principle only if the
PAG value is driven up.
                                                                        3-5

-------
         RADIATION HEALTH EFFECTS
                 (Appendix B)

Acute (deterministic) health effects

Mental retardation

Radiogenic cancers

Thyroid disorders and cancers

Genetic disorders
                                                3-6

-------
1*0
                      Based on minimal
                      medical care
                  Intensive medical care may_
                  increase the dose threshold
                  by :>0 percent
          100     100     300     400
             WHOL1 IODY ABSORBED 009E (rid)
SOO
                                             800
   FIGURE B-1.  ACUTE HEALTH EFFECTS AS A FUNCTION
              OF WHOLE BODY DOSE.
                                                  3-7

-------
  ACUTE HEALTH EFFECTS: CONCLUSIONS
                    (p.B-17)

Dose             Acute Health Effect

50 rad       Less than 2 % of the exposed expected to
            show forewarning symptoms.

25 rad       Forewarning symptoms are not expected.
                                                3-8

-------
        ACUTE HEALTH EFFECTS: CONCLUSIONS
                          (cont'd)

Dose              Acute Health Effect

10 rad       The dose level below which a fetus would not be
            expected to suffer teratogenesis.

5 rad       The approximate minimum level of detectability for
            acute cellular effects using the most sensitive
            methods.
                                                        3-9

-------
         AVERAGE RISK OF DELAYED HEALTH EFFECTS
                   IN THE U.S. POPULATION
                         (pp. B-19 to 25)
Health Effect
Fatal cancers
Nonfatal cancers
Genetic disorders
(all generations)
Effects per Person-rem
Whole
Body
2.8E-4a
2.4E-4
1 .OE-4
Thyroid
3r6E-5b
3.2E-4

Skin
3.0E-6
3.0E-4

a Risk to the fetus is estimated to be 5 to 10 times greater.
b Risk to young children is estimated to be about 1.7 times greater.
 Their dose is also about 2 times greater.
                                                            3-10

-------
            UPPER BOUNDS ON DOSE FOR EVACUATION
             BASED ON COST OF AVOIDING FATALITIES
                         (p. C-1 I and E-2)
Accident
Category
SST- 1 b


SST-2


Atmospheric
Stability Class
A
C
F
A
C
F
Dose Upper Bounds3
Maximum (rem)
5
5
10
1
3.5
10
Minimum (rem)
0.4
0.4
0.8
0.15
0.25
0.7
a Based on an assumed range of $400,000 to $7,000,000 per life saved.
6 SST m ans Siting Sourc Term. See page E-2 of PAG Manual.
                                                              3-11

-------
    CALCULATION OF RADIATION RISK
         VERSUS EVACUATION RISK
                  (p. C-10)

Estimated risk of death from transportation
= 9E-8/person mile.

Assume 100 mile round trip for evacuation.

Estimated risk of death from radiation
= 3E-4/person rem.

Calculate the equivalent risk (rem/100 miles).
                                            3-12

-------
AVERAGE VERSUS CENTERLINE DOSE
            (P- C-12)
Centerline
Dose (rem)
0.5 to 1
1 to 2
2 to 5
5 to 10
Average Dose Avoided by
Stability Class (mrem per individual)
A
340
670


C
190
380
870

F
70
150
330
750
                                   3-13

-------
       MAJOR CONCLUSIONS LEADING TO THE
      SELECTION OF THE PAG FOR EVACUATION
                    (PP.C-I8&C-I9)
•  0.5 rem is the selected dose to be avoided.

   -  This satisfies Principles I and 2.

   -  Cost of going lower is not justified.  (Principle 3)

   -  Net reduction in average risk will occur
      (Principle 4).

   -  Meets acceptable risk to the fetus established for
      occupational exposure.
                                                     3-14

-------
      MAJOR CONCLUSIONS LEADING TO
          THE SELECTION OF I REM AS
          THE PAG FOR EVACUATION
                   (p.C-19)

• If sheltering is implemented to 0.5 rem at centerline,
  and evacuation to I rem, the avoided dose from
  evacuation will be about 0.5 rem.

• Therefore, the PAG recommended for evacuation is
  I rem.
                                           3-15

-------
 BAS S FOR EMERGENCY WORKER DOSE L M TS
                 (pp. C-22 to 24)
5 rem limit unless higher limit is justified

-  Occupational guidance should normally govern.

-  Limit emergency workers to nonpregnant adults.

-  Occupational limits for organs, extremities and lens of
   the eye should also apply.
                                                3-16

-------
      BAS S FOR EMERGENCY WORKER
                 DOSE L M TS
                    (cont'd)

10 rem limit for protecting valuable property

-   Some emergency situations justify dose limits higher
   than 5 rem.

-   ICRP-26 recognizes 10 rem as an annual limit for
   any single event for workers.

Higher limits are conditional.
                                               3-17

-------
       BASIS FOR EMERGENCY WORKER
                  DOSE LIMITS
                     (cont'd)
25 rem limit is justified for:

-  life saving

-  preventing substantial risks to populations

ICRP-26 recognizes 25 rem as a lifetime limit for
specially justified circumstances.

Acute effects to adults will be avoided.
                                                 3-18

-------
          DOSES N EXCESS OF THE L M TS
            FOR EMERGENCY WORKERS

•  Old limits of 75 and 100 rem present unacceptably high
   risk for assignment

•  No limit is needed for persons who volunteer for
   higher doses if:
   -   they are fully aware of the risks involved, and
   -   they are lifesaving or preventing dose to a large
      population.

•  Chart of risks  is provided (see page 2-12).
                                                 3-19

-------
           SESSION 4
APPLICATION AND INTERPRETATION
              OF
   PROTECTIVE ACTION GUIDES
             AND
 EMERGENCY WORKER DOSE LIMITS
              FOR
        THE EARLY PHASE

-------
              MAIN TOPICS
Definitions and interpretations




Special dose quantities and concepts




PAG values and their application




The use of Kl for emergency workers




The impact of the changes to the guidance
                                           4-1

-------
              APPLICABILITY OF PAGs
                    (p. 2-1 & 2-2)
PAGs apply to all nuclear incidents or accidents except
nuclear war.
   Developed based on nuclear power plant accidents
   Dose limits also apply to all	

The implementation guidance applies primarily to nuclear
power plants.
                                                     4-2

-------
                  DEF NITONS
                  (pp.  -2&A-3)

Protective Action Guide (PAG):

The projected dose to individuals in the general
population that warrants protective action.

Projected Dose:

The calculated future dose that would be received by
individuals if no protective actions were taken.
                                                  4-3

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              PAG INTERPRETATIONS
                   (pp. l-l,&l-7)
PAGs are:
   Decision levels for public officials
   Used to minimize risk from an event which is occurring
   or has already occurred
                                                  4-4

-------
              PAG INTERPRETATIONS
               (pp. 2-1,4-1, 2-2, & I -6)
                       (cont'd)
PAGs are:
   Mandatory for planning
   -   but, professional judgment is required for their
      application

   Independent of the type or magnitude of the release
                                                  4-5

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               PAG NTERPRETAT ONS
                   (pp.  -6,  &2-2)
                        (cont'd)
PAGs are:
   A supplement to design safety of nuclear facilities
   Designed to protect all individuals in the population
                                                   4-6

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              PAG INTERPRETATIONS
              (pp. 1-6  2-1 2-4 &2-IO)
                       (cont'd)
PAGs are not:
   The basis for the size of the EPZ
   Dose limits
   Additive to other doses
                                                 4-7

-------
              PAG INTERPRETATIONS
                   (pp. I7&2I)
                       (cont'd)
PAGs do not:

•  Imply an acceptable level of dose for nonemergency
   situations.
   Represent the boundary between safe and unsafe
   conditions.

   Supersede Federal Radiation Council (FRC) Guidance.
                                                 4-8

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              PAG INTERPRETATIONS
                   (pp. A-2 & A-3)
                       (cont'd)
PAGs do not include:

•  Previous radiation doses.

•  Safety factors to account for uncertainties in dose
   projection procedures.
                                                   4-9

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       DOSE QUANTITIES USED
      FOR EMERGENCY RESPONSE
            (pp. B-1 & B-2)
Absorbed dose
Projected dose
Committed dose
                                       4-10

-------
         SPECIAL DOSE QUANT T ES
                 (p.B-  &B-2)

Dose equivalent (DE)
-  Organ dose
-  Risk of cancer

Committed dose equivalent (CDE)
-  50 years

Effective dose equivalent (EDE)

Committed effective dose equivalent (CEDE)
                                              4-11

-------
 TOTAL EFFECTIVE DOSE EQUIVALENT (TEDE)

TEDE (an NRC term) means the sum of the deep dose
equivalent from external gamma radiations (EDE) and
the committed effective dose equivalent (CEDE) from
internal exposures.

Plume PAGs are expressed as this sum.
"TEDE" is not used in the PAG Manual

EDE from external sources is the same as NRCs term
"deep dose equivalent"
                                            4-12

-------
                    EARLY PHASE PAGs
                   (pp. 2 5 to 2 8 & C 20)
                          (cont'd)

Projected dose (rem)       Action

I  to 5 TEDE        Evacuation (or, for some
5 to 25 CDE thyroid  situations, sheltering)
50 to 250 DE skin    should normally be initiated
                    at the lower end of the range.

25 CDE thyroid      Administer stable iodine (Kl)
from radioiodine     to the public in accordance with
                    State medical procedures.
                                                        4-13

-------
          OTHER EARLY PHASE GUIDANCE
                    NOT PAGS
                   (pp. 2-4 to 2-9)

Projected dose (rem)      Action

<0.1 TEDE              No action based on risk
<0.5 CDE thyroid        from radiation dose.
<5 DE skin

0.1 to < I  TEDE       Sheltering should be
0.5 to <5 CDE thyroid considered, but this is not a
5 to <50 DE skin        PAG for sh  It ring.
                                                4-14

-------
                DIFFERENCES IN
          EMERGENCY WORKER LIMITS
       AND PROTECTIVE ACTION GUIDES
   Difference in justification
•  Difference in time period of exposure
   Limits vs threshold for decisions
                                             4-15

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    EMERGENCY WORKER PROTECTION
         (pp. 2-9 to 13 and C-22 to 24)
Period of application of emergency worker limits

Emergency worker dose and occupational dose are not
additive unless required by license.

No guidance for keeping records of dose to emergency
workers

Protection of minors and fetuses
                                             4-16

-------
     EMERGENCY WORKER CATEGORIES
                   (p. C-22)

Designated by State and local authorities

Example categories:

-   Law enforcement and traffic control officials
-   Medical and public health personnel
-   Environmental monitors
-   Emergency vehicle operators
-   Utility,  industrial, and institutional emergency
   workers
                                               4-17

-------
              PERSPECT VES FOR
         EMERGENCY WORKER L M TS
                (pp. C-22 to 24)

Apply the same dose limits as for occupational!/
exposed workers wherever practicable.

Permit higher dose limits when required to prevent
substantial risks to populations or protect valuable
property.

Provide guidance for extreme emergencies.
-  Volunteers fully informed of risks
                                              4-18

-------
     DOSE LIMITS FOR EMERGENCY WORKERS (p. 2-10)
DOSE
LIMIT
5 rem
10 rem
25 rem
    ACTIVITY

          all
protecting valuable
   property
life saving or protecting
   large populations
>25 rem  life saving or protecting
             large populations
 CONDITION
lower dose not
   practical
lower dose not
practical
only on a voluntary
basis to persons
   fully aware of the
   risks.
                                                        4-19

-------
              Kl FOR EMERGENCY WORKERS
                     (pp. 2-11 and 2-13)
• Kl is recommended if atmospheric releases include radioiodine
  (no  dose threshold).
  State medical procedures determine its availability and proper
  use.
                                                        4-20

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           SESSION 5
INTRODUCTION TO DOSE PROJECTION
              FOR
    PROTECTION OF THE PUBLIC
             AND
      EMERGENCY WORKERS

-------
           GENERAL APPROACH
           TO DOSE PROJECTION

Determine or estimate source term (Q) and
projected release duration (Tp).

Use atmospheric dispersion model to calculate time
integrated air concentration (Xin).

Use dose models to calculate projected dose (D) by
means of dose conversion factors (DCF).
                                             5-1

-------
               GENERAL APPROACH FOR CALCULATING
                             PROJECTED DOSE
Measure or calculate environmental
concentrations.
Multiply by duration of exposure to get time
integrated concentration (Xin) for each
nuclide or group of nuclides.
Multiply each Xin by the appropriate DCF to
get TEDE or thyroid dose from each nuclide
or group of nuclides.
Sum TEDEs over all nuclides or groups of
nuclides and su  thyroid doses to get
projected doses co  parable to PAGs.
Concentrations may be for indivi-
dual nuclides or may be grouped
by iodines and noble gases.
True Xin can be calculated if the
total release is used. Not used with
measured concentrations.
Use DCFs from PAG Manual
Table 5.1 for TEDE and 5.2 dose
for CDE to thyroid from single
nuclides. For groups of nuclides,
DCFs must be calculated.  A DCF
for participates, as a group, is not
practical.
                                                                             5-2

-------
     NEEDED SOURCE TERM INFORMATION
Gross noble gas, radioiodine, and participate release
rates
                       or

   curies per second of each radionuclide

Release height  (release point information)

Estimated release duration
                                                 5-3

-------
      NEEDED METEOROLOGY
Wind speed,
Wind direction
Stability Classes




Mixing depth




Predicted changes
Precipitation




                                          5-4

-------
     GAUSSIAN DISPERSION EQUATION
      Xu
       •••^^^^^

       Q
\
2

y
 n a  a
     y
                                2

                                z
For a ground level release, release height (h) = 0,

  At the centerline, the lateral distance (y) = 0.

             Xu          1
                        n a  a
                           y
                                                5-5

-------
              BASIC DOSE EQUATION
The basic dose equation is:

                   D = Xin - DCF

D     =  Dose (rem)

Xin =  Time integrated concentration in air
         (uCi • cm"3 • h)

h     =  duration of exposure (hours)

DCF  =  Dose conversion factor
         (r m p r uCi - cm"3 • h)
                                                   5-6

-------
       NEEDED NFORMATONFOR
          DOSE CALCULAT ONS

Radionuclide air concentration (X)

Expected duration of exposure (Tp)

Dose conversion factors (DCF)

Dose projection procedures
-   computer programs
-   RASCAL
                                          5-7

-------
   INFORMATION NEEDED TO SUPPORT
     PROTECTIVE ACTION DECISIONS
Total effective dose equivalent (TEDE).

Committed thyroid dose (CDE).

Measurements of plume gamma rate.

Measurements of gross radioiodine concentrations,
                                          5-8

-------
             TIME INTEGRATED
         AIR CONCENTRATION, X
                                 in
Air concentration times projected exposure time,
          X(uCi/cm3) • Tp(hour) = Xin
Permits addition of the dose conversion factors over
the three exposure pathways.
                                            5-9

-------
            TIME INTEGRATED
        AIR CONCENTRATION, Xin
                   (cont'd)


High concentration for short time


Low concentration for long time.


Symbol:  Xin


Matches units of EPA's dose conversion factors,
                                           5-10

-------
               TIME INTEGRATED
           AIR CONCENTRATION, Xin
                     (cont'd)
PROBLEM ONE
  Xe-l 33 air concentration is I .OE-4 uCi/cm3
   Expected duration of air concentration is 2 hours,

   Xin equals ??????  (uCi • cnV3 • h).
                                              5-11

-------
               TIME INTEGRATED
           AIR CONCENTRATION, Xin
                      (cont'd)

PROBLEM TWO

•  Xe-133 air concentration is 5.0E-5 uCi/cm3.

•  Expected duration of this air concentration is 240
   minutes.

•  Xin equals ??????  (uCi • cm'3 • h).
                                              5-12

-------
               TIME INTEGRATED
           AIR CONCENTRATION, Xjn
                     (cont'd)

SOLUTIONS TO PROBLEMS I AND 2

• Xin = (air concentration) (expected exposure time)

• Xin = (I.OE-04uCi/cm3)(2h)
     = 2.0E-04 uCi • cm'3 • h

• Xin = (5.0E-05 uCi/cm3) (240m/60m/h)
     = 2.0E-04 uCi • cnY3 • h
                                            5-13

-------
              DCF DEFINITION
                  (p.A-l)
Dose Conversion Factors (DCF) change
environmental concentrations (or time integrated
concentrations) to dose.
Dose units (rad = rem)
                             -3
EPA DCF unit:  rem per uCi • cm  • h
                                            5-14

-------
      PARAMETERS THAT AFFECT DCFs
Physical characteristics
Chemical characteristics
Breathing rates




Assumed deposition velocities




Biological system clearances
                                              5-15

-------
   ASSUMED VALUES FOR CALCULATIONS

Breathing rate = 1.2 m3/h

Deposition velocity   EPA          RASCAL
-  Iodine           I cm/s        0.3 cm/s
-  Participates       0.1 cm/s      0.3 cm/s

Gamma shielding factor due to ground roughness
EPA  =   I       RASCAL default  =  0.7

Public exposure to deposited materials before
relocation is 4 days (96 h)
                                            5-16

-------
    DOSE CONVERSION FACTOR TABLES
         (TABLE 5-1 AND TABLE 5-2)

Table 5-1: Dose Conversion Factors and Derived
Response Levels for Combined Exposure Pathways
During the Early Phase of a Nuclear Incident.

Table 5-2: Dose Conversion Factors and Derived
Response Levels - Inhalation of Radioiodine.

Refer to EPA Manual
                                             5-17

-------
                SKIN DOSE
DCFs for skin are not provided for early phase.
Skin dose is not expected to be controlling.
Skin dose is controlled by bathing and changing
clothing.
                                             5-18

-------
    US NG DCFs FOR COMB NED PATHWAYS
                   (TABLE 5- )

GIVEN:
-  The concentration of tritium (H-3) in a plume is
   5E-3 Ci/m3.

   Exposure to plume expected for 3 hours.

PROBLEM:
-  What is the time integrated air concentration?
-  What is the dose conversion factor?
-  What is the projected dose?
-  What kind of dose is it?
                                                 5-19

-------
     USING DCFs FOR COMBINED PATHWAYS
                   (TABLE 5-1)
                      (cont'd)

SOLUTION:  Calculate Xin and look up the DCF.

•  Xjn = (air concentration) (expected exposure time)
      = (5E-3 uCi/cm3) (3 hours)

•  Xin= l.5E-02uCi-cm-3'h

•  DCF for tritium from Table 5-1 is
   7.7E+01 rem per uCi • cm"3 • h
                                               5-20

-------
     US NG DCFs FOR COMB NED PATHWAYS
                    (TABLE 5- )
                       (cont'd)

•  Projected dose = Xjn times DCF
                        or
(I.5E-2 uCi • cm"3 • h)(7.7E+l rem per uCi • cm"3 • h)

•  Projected dose = 1.2 rem

•  This projected dose is considered to be total effective
   dose equivalent (TEDE).  Why?
                                                 5-21

-------
      USING DCFs FOR COMBINED PATHWAYS
                    (TABLE 5-1)
                       (cont'd)


THE PROJECTED DOSE IS THE TEDE BECAUSE:


•  DCF is based on committed effective dose equivalents.


•  All significant early phase exposure pathways are
   included.


•  All significant radionuclides are included.
                                                 5-22

-------
                  SUMMARY
                  n


            D  = S  DCF ' X
                          *    mm
                          i   in, i
      = DCF for radionuclide (i)
n     = Number of radionuclides present
Xjn,   = The time integrated concentration of

        radionuclide (i)
                                                5-23

-------
          SESSION 6
     IMPLEMENTATION OF
EMERGENCY WORKER DOSE LIMITS

-------
                MAIN TOPICS
Emergency workers




Relative importance of exposure pathways
Inhalation dose control methods
PAG Subcommittee guidance
Dose for the record
                                              6-1

-------
            EMERGENCY WORKERS
                    (p. 2-9)

State responsibility for defining emergency workers

Example assignments

-  Law enforcement/traffic control

-  Radiation protection

-  Transportation services
                                                6-2

-------
         EXPOSURE PATHWAYS FOR
           EMERGENCY WORKERS

External gamma radiation
   Plume
-  Groundshine

Inhalation from the plume and resuspended materials
   Plume inhalation may be the major pathway

External beta radiation
   Plume
   Groundshine
   Deposited materi Is on skin nd clothing
                                               6-3

-------
       INHALATION OF RESUSPENDED MATERIAL

•  R suspension r t s
   -   Empirical values range from I0~5 to I0~9 nrf1

•  Importance of pathway

      Plume phase

      Post plume phase

   -   For example, at I0~5 m"1, I mR/h yields about 0.05 mrem
      CEDE from inhalation
                                                   6-4

-------
EXAMPLE DOSES FROM A REACTOR ACCIDENT
RTM-93 CASE 5; Gap release for one hour; Late release @ 100 % per day
  No Spray; No protective action; No rain; Met cond. was not
  1,000
                                       Rem Versus Distance
                                       — Thyroid Dose
                                       -+-TEDE
      1
 2         5
Distance (miles)
10
                                                   6-5

-------
   EXAMPLE DOSES FROM A REACTOR ACCIDENT
  RT -93 CASE 16 Severe core damage' 100% per hour leak rate-
No spray; o rain; No protective action;  et Cond was not Specified.
  100,000
   10,000
1,000
                                        Rem Versus Distance
                                        —• Thyroid Dose
                                        — TEDE
        1
             2        5
            Distanc (mile )
10
                                                     6-6

-------
        INHALATION DOSE CONTROL
             USING RESPIRATORS

Mentioned, but not promoted by EPA or FEMA

Effectiveness
-  Filter type
-  Air supplied type

Advantages
-  Protects workers from inhalation dose.
-  Dose control by dosimeter is simple.
                                             6-7

-------
        INHALATION DOSE CONTROL
             USING RESPIRATORS
                    (cont'd)

Disadvantages
-   OSHA requirements
      Fitting and testing
   •   Training
      Medical examinations
-   No beards
-   Reduced vision, communication, and efficiency
-   Discomfort
-   Logistics
                                              6-8

-------
          PAG SUBCOMMITTEE GUIDANCE
                 DATED JULY 1994

ISSUE:   How should the dose to emergency workers,
        especially those exposed to a radioactive plume,
        be monitored and controlled to meet the EPA
        dose limits in terms of total effective dose
        equivalent (TEDE)

•  Guidance:
   -  Relates to accidents at nuclear power plants
   -  Based on current practices
   -  Other approaches may be acceptable
                                                 6-9

-------
       PAG SUBCOMMITTEE GUIDANCE
                  (CONTINUED)

Maintain 5 rem TEDE limit where practicable.

The primary activities for emergency workers within an
airborne plume will be:
-  Protection of valuable property,
-  Protection of large populations, and
-  Monitoring.

States should maintain flexibility in dose limits
                                                6-10

-------
       PAG SUBCOMMITTEE GUIDANCE
                    (cont'd)

Doses up to 10 and 25 rem (and above) should be
accepted and planned for.


DRDs may be used to estimate inhalation dose.


Use of Kl is recommended.


Flexibility in control procedures is granted.


Three acceptable options are presented.
                                              6-11

-------
   OPTIONS FOR ADJUSTING EMERGENCY WORKER
         GAMMA DOSE LIMITS TO ACCOUNT
      FOR SIGNIFICANT PARTICULATE RELEASES
  Options'
 Evacuation Phase
  Post-Evacuation Phase
      I
No adjustments
Adjust, if necessary
             Fixed admin, limit
             set prior to Emrg.
                 Adjust, if necessary
            Contextual
            adjustment based
            on plant data
                 Contextual adjustment
                 based on plant and
                 environmental data
lOth  r options may be consid r d
                                                 6-12

-------
                  OPTION ONE

Control only whole body g mma  nd thyroid dose
during evacuation.

Rationale
   Not practical to rotate workers
   Inhalation dose is controlled for tasks after evacuation.
   Evacuation may be completed before plume    arrives.

Disadvantages
   Higher risk of over-exposure compared to other
options
                                                     6-13

-------
                 OPTION TWO

 Pre-established administrative limits

Rationale
-  Easy to implement
-  Will meet limits for most probable accidents

Disadvantages
-  May not provide adequate control for the most
   severe accidents
-  Possible discontinuity between States
                                                 6-14

-------
         DOSIMETER ADJUSTMENT FACTORS
Accident
Category
BWR-I
PWR-I
BWR-3
PWR-3
PWR-5
PWR-7
Adjustm nt F ctors3
With Kl
13 to 29
8 to 16
3 to 7
4 to 8
1.4 to 2
1 to 2
Without Kl
16 to 37
1 1 to 26
5 to 12
6 to 14
3 to 6
1 to 2
a Calculated for distances ranging from I to 25 miles, stability classes ranging
from A to F, and for 13 hours of exposure.
                                                       6-15

-------
                   OPTION THREE
•  Calculate contextual mission limits applicable to the
   accident in progress.

•  Rationale
   -  Can use same data as for dose projection
   -  Mission limits would be more defendable.

•  Disadvantages
   -  Variable limits may be confusing to implement.
   -  Necessary data may not be available.
                                                   6-16

-------
   RETROSPECTIVE EVALUATION OF DOSE
              FOR THE RECORD
Applicable to emergency workers who are exposed to
an airborne plume containing iodines and/or participate
materials
Kl administration affects the evaluation.
                                             6-17

-------
     RETROSPECTIVE EVALUATION OF DOSE
               FOR THE RECORD
                    (cont'd)

Based on dosimeter readings (primarily TLD) and
-  Release composition
-  Environmental data (importance of air samples)

Or based on dosimeter readings and
-  Release composition
-  Whole body counts
-  Bioassay
                                              6-18

-------
      RETROSPECTIVE ANALYSIS USING
    RELEASE AND ENVIRONMENTAL DATA

Need measured dose rates and air sample data.

Dose rate measurements by air sampling teams relate
air concentrations to dosimeter readings.

Calculations of ratio of exposure rate to air
concentration allows worker dosimeter readings to be
related to TEDE - becomes official record.
                                             6-19

-------
                     RETROSPECTIVE - PROBLEM

Monitoring data at location A:
GM counter (closed beta shield, I m) - 950 mR/h
GM counter (open beta shield, I m - open window pointing up)  - significantly higher

Air sample is collected at location A and sent to the laboratory for analysis.  The laboratory reports
the following results:

    Ce-I4l    I.Oe-05  uCi/cm3
    Ba-140    I.Oe-04  uCi/cm3
    Cs-134    I.Oe-05  uCi/cm3

WHAT CONCLUSIONS CAN BE REACHED IMMEDIATELY FOR LOCATION A?

WHAT ARE THE FOLLOWING FROM A I HR EXPOSURE?

    IMMERSION PLUS DEPOSITION DOSE (EDE)?
    INHALATION DOSE (CEDE)?  (See WORK SHEET on VG 6-22.)
    TOTAL DOSE (TEDE)?

WHAT IS THE DOSE TO EMERGENCY WORKERS EXPRESSED AS TEDE PER ROENTGEN AS
READ  ON A DOSIMETER?


                                                                         6-20

-------
               RETROSPECTIVE - PROBLEM  SOLUTION

Immediate conclusions:

     There had been a release of radioactive materials.

     The plume was present.

     Particulates were present

     Actual risk could be much higher than implied by dosimeter readings.

Compare DCFs from plume shine versus ground shine for Cs-l 34.  (The DCF for deposited
materials assumes persons remain 96 hours (4 days) at this location - correct for this).

     The deposition dose is not significant because the I hr DCF is small compared to the
     immersion DCF.

Assuming "mR" is approximately equal to "mrem", the whole body dose rate from gamma radiations
(EDE/h)  is:
                                 950 mrem/h

Gamma dose (EDE) due to a I  hour external exposure to the  plume and groundshine
                     950 mrem/h • I h = 950 mrem  = 0.95 rem


                                                                               6-21

-------
                  PROBLEM SOLUTION WORK SHEET
Problem Emergency worker   : Projected Dose at Location A  from inhalation



Nuclide(s)


Ce-I4l
Ba-140
Cs-134


Air
Concentration
(X)
(uCi/cm3)

I.OE-05
I.OE-04
I.OE-05


Projected
Exposure
Time
(h)





Integrated
Air
Concentration
(Xin)
(uCi • cm "3 • h)






DCF from
Table 5-4
(rem per
uCi • cm'3 • h)
•



Totals >
Inhalation
Committed
Effective Dose
Equivalent
(CEDE)
(rem)




                                                                    6-22

-------
                                PROBLEM SOLUTION
                                      (cont'd)

•   Total projected dose (TEDE) to worker for nominal I hour exposure to plume:
                    0.95 rem (EDE)  + 1.12 rem (CEDE) + 0.00 (EDE) =
                                  2.07 rem (TEDE)

*   Nominal expected increase in dosimeter reading after I hour is:

                     0.95 rem (EDE) due to gamma from the plume +

               approximately 0.00 rem (EDE) due to gamma from ground shine

                         total is 0.95 "R" recorded on dosimeter

•   0.95 "R" Dosimeter reading is equatable to a total dose for the record:
                                  2.07 rem (TEDE)

•   Retrospective dose for the nominal worker record:

                 each 1.0 "R" on dosimeter is equivalent to 2.2 rem (TEDE)
                                                                                6-23

-------
            FACTORS THAT MAY
       AFFECT DOSE CALCULATIONS

Insufficient air sample and exposure rate data

Ground shine becomes important.

Emergency workers get significant doses outside the
plume.

Emergency workers do not take Kl.

Emergency workers use respirators.
                                            6-24

-------
          PLAN CHANGES NEEDED
        TO SUPPORT OPTIONS I OR 2
Specify the administrative dose limits for evacuation
support.
Specify procedures for dose control after evacuation is
complete.
                                            6-25

                                            	I

-------
          PLAN CHANGES NEEDED
           TO SUPPORT OPTION 3

Specify procedures for contextual determination of
administrative dose limits.
-  Calculation models to be used
-  Data needs
-  Sources of data

Identify communication procedures and equipment.

Procedures for changing the administrative limits if
applicable
                                              6-26

-------
      GU DANCE APPL CABLE TO ALL OPT ONS

•  Other options may be selected.
   -   FEMA will review written proposals.

•  FEMA recommends admin, limits of 2 R or more.

•  Need procedures for:
   -   Retrospective dose determinations
   -   Training

•  Existing dosimetry systems are acceptable.

•  Kl use is recommended.
                                                  6-27

-------
  SESSION 7
DEVELOPMENT
     OF
DCFs AND DRLs

-------
        IMPLEMENTATION OF PAGS

Must compare a projected TEDE or CDE to the
applicable PAG

BASIC DOSE EQUATION

-  Dose (TEDE or CDE) = Dose Rate x Time

-  Dose Rate = Concentration x Conversion
   Factor

- Dose = Time Integrated Concentration x DCF
                                         7-1

-------
                   DEF N T ONS

•  Dose Conversion Factor (DCF): A value that
converts an environmental level to dose.
   -   Tabulated in units of: rem per uCi • cm  • h

   Derived Response Level (DRL):  Calculated
   environmental level that corresponds to a particular
   PAG.

   -   Tabulated in units of: uCi • cm"3 • h
                                                 7-2

-------
                PATHWAYS
          (PAG Manual - Section 5.6)

Three exposure pathways are included:
- Gammas from the plume (immersion)
- Inhalation from plume
- Gammas from ground shine (deposited
radionuclides)

Pathways considered, but not included:
-  Beta due to skin deposition
-  Inhalation of resuspended materials
-  Beta from the plume
                                             7-3

-------
   SUPPORTING DOCUMENTS FOR DCFS

"External Dose-Rate Conversion Factors for
Calculation of Dose to the Public" (DOE/EH 0070)
-  Needed for plume and ground shine
"
 Limiting Values of Radionuclide Intake and Air
Concentration and, Dose Conversion Factors for
Inhalation, Submersion and Ingestion" (FGR-I I)
EPA 520/1-88-020 (September 1988).
-  Needed only to modify EPA DCFs for inhalation
                                            7-4

-------
               TIME INTEGRATED
           AIR CONCENTRATION, Xin

   Air concentration times projected exposure time.
            X(uCi/cm3) • Tp(hour) = Xin
•  Permits addition of the dose conversion factors
over the three exposure pathways.
                                               7-5

-------
EXTERNAL EXPOSURE TO GAMMA RADIATION
             FROM THE PLUME
                (Section 5.6.1)

 Table 5-3 (PAG manual, beginning on P. 5-25)

 Gamma radiation due to immersion.

 Conservative if plume is overhead.

 Semi-infinite source assumption.
                                           7-6

-------
EXTERNAL EXPOSURE TO GAMMA RADIATION
             FROM THE PLUME
                   (cont'd)

 DCFs yield effective dose equivalent (EDE).


 Based on DOE/EH-0070; EPA FGR #12.


 Short-lived daughters are accounted for.
                                           7-7

-------
Table 5-3:  Dose Conversion Factors (DCF) and Derived Response
          Levels (DRL) for External Exposure Due to Immersion in
          Contaminated Air
Radionuclide
 DCF
 rem per
              uCi • cm • h
DRL
 uCi
cm
   -3
 H-3
 C-14
 Na-22
 Na-24
 P-32
O.OE+00
O.OE+00
I.3E+03
2.7E+03
O.OE+00
PAG Manual - beginning on page 5-25
  O.OE+00
  O.OE+00
  7.8E-04
  3.7E-04
  O.OE+00
                                                        7-8

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       INHALATION FROM THE PLUME
                (Section 5.6.2)

Table 5-4 (PAG manual, beginning on 5-31)

Inhalation of radioactive participate material

Alpha, beta and gamma emitters

Chemical and physical form that yields the highest
dose
                                              7-9

-------
       INHALATION FROM THE PLUME
                (Section 5.6.2)
                    (cont'd)

Committed effective dose equivalent (CEDE)

Radionuclides may remain in the body,

50 year time frame for dose


Federal Guidance Report No. 11


Standard  Person
                                             7-10

-------
Table 5-4:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for Doses Due to Inhalation
               Lung      DCF            DRL
Radionuclide    Class      rem per      uCi • cm"3 • h
                       uCi • cm"3 • h
 H-3           V          7.7E+OI            I.3E-02
 C-14       LORGC3    2.5E+03             4.0E-04
 Na-22         D          9.2E+03            I.IE-04
 Na-24         D          I.5E+03            6.9E-04
 P-32          W         I.9E+04            5.4E-05

aL ORG C denotes labelled organic compounds

PAG M nual - beginning on pag  5-31
                                                                7-11

-------
Table 5-4:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for Doses to the Thyroid Due to Inhalation
               Lung       DCF           DRL
Radionuclide    Class       rem per       uCi • cm"3 • h
                        uCi •  cm"3 • h
 Te/l-132       W/D       2.9E+05            I.8E-05
 1-125         D         9.6E+05            5.2E-06
 1-129         D         6.9E+06            7.2E-07
 1-131          D         I.3E+06            3.9E-06
PAG Manual - beginning on page 5-35
Also see Table 5-2 on page 5-15
                                                                 7-12

-------
 EXTERNAL DOSE FROM DEPOSITED MATERIALS
                  (Section 5.6.3)

•  Table 5-5 (PAG manual, beginning on 5-37)

•  Gamma radiation following deposition

•  Radioiodine and particulates from a plume

•  Assumes 4-day exposure

•  Dry deposition
                                              7-13

-------
EXTERNAL DOSE FROM DEPOSITED MATERIALS
                    (cont'd)


 Deposition velocity


 -  0.1  cm/s for participate materials


 -   I cm/s for radioiodine


 -  Much higher if there is rain
                                             7-14

-------
     EXTERNAL DOSE FROM DEPOSITED
                 MATERIALS
                    (cont'd)


DCF for deposited materials is the effective dose
equivalent (EDE) in rem per:

-  I uCi/cm3 concentration of a radionuclide

-  I hour of deposition


-  96 hours of exposure to decaying radionuclides
                                              7-15

-------
       TABLE 5-5: DCF EQUATION
          FOR GROUND SHINE
            (pp.  5-34 and 5-37)
   DCF = V  • DRCF
          g
1.14E-3
                              1-e
                                 -At
           A
DCF = the dose per unit air concentration
      (rem per uCi • cm"3 • h)
                                        7-16

-------
            TABLE 5-5  DCF EQUATION
                        (cont d)
  »
•  VB     = deposition velocity (cm/h)
    o

•  DRCF    = the dose rate conversion factor from
             DOE/EH 0070 (mrem/y per uCi/m2)

•  I. I4E-3   = conversion factor from mrem/y per uCi/m2
   to rem/h per uCi/cm2

•A        = decay constant (h"1)

•  t         = duration (h), assumed to be 96 hours
                                                  7-17

-------
Table 5-5:   Dose Conversion Factors (DCF) and Derived Response levels
           (DRL) for a 4-Day Exposure to Gamma Radiation from
           Deposited Radionuclides

                      DCF                       DRL
Radionuclide          rem per               uCi • cm"3 • h
                  uCi • cm"3 • h
 H-3                 O.OE+00
 C-14                O.OE+00
 Na-22               8.3E+03                  I.2E-04
 Na-24               3.IE+03                  3.2E-04
 P-32                O.OE+00

PAG Manual - beginning on page 5-37.
                                                             7-18

-------
  MOD FY NG DOSE CONVERS ON FACTORS
Changes in physical characteristics




Changes in chemical characteristics




Changes in breathing rates




Changes in assumed deposition velocities
                                               7-19

-------
           COMBINED PATHWAYS
                (PAGM nua.T b 5- )

The DCF and DRL for each pathway is related to the
time integrated air concentration (Xin). They may be
combined for a particular radionuclide

DoseTotal  = DoseExt+ Doselnh + Dose^^ shine
DoseTotal  = DCF^  • Xin + DCFlnh • Xin
              DCFGS • Xin
DoseTotal  = Xin • (DCFB.+ DCFinh + DCFGS)
                                              7-20

-------
Table 5-1:   Dose Convers'on Factors (DCF) and Derived Response levels
           (DRL) for Comb'ned Exposure Pathways Dur'ng the Early
           Phase of a Nuclear Incident

                      DCF                       DRL
Radionuclide          rem per                uCi • cm"3 • h
                  uCi • cm"3 • h
H-3
C-14
Na-22
Na-24
P-32
7.7E+OI
2.5E+03
1 .9E+04
7.3E+03
1 .9E+04
I.3E-02
4.0E-04
5.3E-05
1 .4E-04
5.4E-05
PAG M nual - begin ing on p g  5-9.
                                                             7-21

-------
      EXAMPLE OF COMBINED PATHWAYS
Nuclide selected

Pathway
External
Inhalation
Ground Shine
Table
5-3
5-4
5-5
Summation
DCF
(rem per uCi • cm " 3 • h)




xir
(uCi • cm"3 • h)
1
1
1

Dose
(rem)





Combined
5-1

1

                                         7-22

-------
        SESSION 8
DOSE PROJECTION PROBLEMS
   FOR THE EARLY PHASE

-------
              INTRODUCTION

Two student problems

I.  Use of combined pathways DCFs
    I a-1 Thyroid dose at I  mile
    Ib-l TEDEat I mile
    la-2  Thyroid dose at 2 miles
    I b-2 TEDE at 2 miles

2.  Use of separate pathway DCFs
                                         8-1

-------
    STEPS TO DETERMINE THE REQUESTED
             PROJECTED DOSES

Determine diffusion coefficients (Xu/Q) at the distances
required.

Determine the wind speed in m/s (u).

Determine the source term in Ci/s (Q).

Solve for X.
                                             8-2

-------
     STEPS TO DETERMINE THE REQUESTED
              PROJECTED DOSES
                     (cont'd)

Determine the projected exposure time (Tp).

Calculate the time integrated concentration (Xin).
Select the specific DCF (rem per jjCi • cm" • h).

Calculate the projected dose (rem).
                                              8-3

-------
           PROBLEM : PROJECTED DOSE
         US NG COMB NED PATHWAY DCFs
  t
Problem la: Determine the Committed Dose Equivalent
           (CDE) to the thyroid from a plume containing
           l-!3l,and

Problem I b: Determine the Total Effective Dose Equivalent
           (TEDE) for a plume with a mix of three
           isotopes (Xe-133, I-131, and Cs-134).

And:          Determine the above doses at I  mile and 2
              miles from the release point.
                                                8-4

-------
                   PROBLEM I
Calculate at I mile
  -  Concentrations (X)




  -  Time Integrated Concentration (Xjn)




  -  Dose (CDE to Thyroid and TEDE)




Use Worksheet (VG 8-6)
                                               8-5

-------
1
Problem 1 a -
RAD AT C
& 1 b- 1 : Proiec

Nuclide(s)
& Prblnv
# la-l

1-131


Nuclide
# Ib-l
Xe-133
1-131
Cs-134

Xu/Q
@ 1 mi
(m-2)









Q
(Ci/s)









>NA<
ted Do
u
(m/s)









CCDEr
WOR
se at 1 Mi

X
@J_mi
(pCi/cm3)









sIT ASSESSMENT COURSE
X SHEET
le(s): From thyroid & combined pathway
Exp.
time
(h)"









Xm
@ 1 mi
(pCi • cm'3- h)









DCF
Table
No.









DCF^
rem
pCi • cm"3- h




DCFCP



TOTAL -
Dose
(CDE)
(rem)



TEDE
(rem)





8-6

-------
         PROBLEM I .-INITIAL CONDITIONS
• Time from shutdown to release: 2 hours
  Estimated release time: 3 hours
  Release height: Ground level




  Stability is class D.




  Wind speed is 2 m/s (4.5 mph).




  Forecast is for no change.
                                                 8-7

-------
XQ/Q AS A FUNCTION OF
DOWNWIND DISTANCE AND
STABILITY CLASS
Values of Xu/Q (nV2)











Distance
(Miles)
0.5
1
2
3
4
5
7
10
IS
Class
A
6.6E-6
1 .OE-6
5.5E-7
3.9E-7
3.0E-7
2.5 E-7
I.9E-7
1 .4E-7
9.9E-8
Class
B
3.0E-5
7.4E-6
I.9E-6
8.4E-7
4.8E-7
3.3E-7
2.5E-7
1 .8E-7
I.3E-7
Class
C
7.6E-5
2. 1 E-5
6. 1 E-6
2.9E-6
1 JE-6
1 .2E-6
6.3E-7
3.3E-7
1 .8E-7
Class
D
2. 1 E-4
7.0E-5
2.4E-5
I.3E-5
8.5E-6
6. 1 E-6
3.7E-6
2.3E-6
1 .2E-6
Class
E
4.2E-4
I.4E-4
5.0E-5
2.8E-5
1 .9E-5
1 .4E-5
8.4E-6
5. 1 E-6
3. 1 E-6
Ciass
F
9.6E-4
3.3 E-4
1 .2E-4
6.8E-5
4.6E-5
3.3E-5
2.2E-5
1 .4E-5
8.4E-6











A 1250 meter lid is used.
This is a ground level release.
8-8

-------
        PROBLEM I:  SOURCE TERM
SOURCE TERM (Q):




  - Xe-133         l,700Ci/s
  - 1-131           0.17 Ci/s
  - Cs-134         0.05 Ci/s
                                          8-9

-------
                  PROBLEM I a-1
       CALCULATE AIR CONCENTRATION (X)

•  At I  mile and for I-131:

           XQ/Q = 7.0E-05  (from VG 8-8)

•  WHERE:
     X = air concentration (pCi/cm3)
     U = average wind speed (mis)
     Q = source term (Ci/s)

•  SOLVE FOR X AT I MILE:
                                             8-10

-------
        PROBLEM I a-1:  CALCULATE
   INTEGRATED AIR CONCENTRATION (XJ
                FORI-I3I
Using values recorded on the Work Sheet
Solve for Xin:
                Xin = X • t
                                        8-11

-------
                  PROBLEM I a-1

       COMMITTED DOSE EQUIVALENT (CDE)

                 TO THE THYROID




 The committed dose equivalent (CDE) to the

   thyroid is:




 	 (Xin • DCFth)
•  The dose model is:
,
th
^
th
X  =
 in
                          ^
                          th
g.
u
XM
~Q
                                       h
                                             8-12

-------
         PROBLEM Ib-l: PROJECTED DOSE




Calculate the TEDE for three nuclides:

  Xe-133,1-131, and Cs-134.
Assumptions: Same as for problem I a-1
Dose Model:
     TEDE = DCF  • X
                 cp   in
= DCF
      cp
                                     X*/
u   Q
         h
                                             8-13

-------
                 PROBLEM Ib-l
             SOLVE FOR X AT I MILE
             FOR THREE NUCLIDES
Model:
  X =
Xu   Q
 Q   »
                  Calculate concentrations (X)
                 Xe-133,  Q
                  /-131,  Q
                 Cs-134,  Q
I.IE+3
\.7E-l
5.0E-2
                                7.0E-5 =
  Q = 2 m/s
                                            8-14

-------
                   PROBLEM Ib-l
       INTEGRATED AIR CONCENTRATION (Xin)
  Using the results from VG 8-14
  Solve for X.n for the three nuclides,
          'in
• Exposure duration = 3 hours
                                               8-15

-------
                 PROBLEM la-2
      SOLVE FOR (CDE) TO THE THYROID FROM
                 I-131  AT 2 MILES
                CDE. = DCF. • X.
                   th      th    in
•  Step I.  Obtain XG/Q for 2 mi = 2.4E-5. (VG 8-8)
  Step 2.
X =
2.5E-5 m~2 • \.lE-\Cils
        1 mis
                                            8-16

-------
                   PROBLEM la-2
SOLVE FOR THE (CDE) TO THE THYROID FROM 1-131  AT
                      2 MILES

•  Step 3. Xin = X • h  =

•  Step 4. Obtain DCFth.  The Table is     .
     The value is
• Step 5. Dose = Xin •  DCFth =
  Use the Worksheet on VG 8-18
                                              8-17

-------
       RAD AT ON ACC DENT ASSESSMENT COURSE
                       WORK SHEET

Problem la-2 & lb-2  : Projected Dose at 2  Mile(s): From thyroid & combined  pathway
Nuclide(s)
& Prblm.
# la-2

1-131


Nuclides
# lb-2
Xe-133
1-131
Cs- 1 34

XQ/Q
@J_mi
(m-2)










Q
(Ci/s)










0
(m/s)










X
@_2jni
(MCi/cm3)










Exp.
time
(h)










xin
@2mi
(pCi • cm"3 • h)










DCF
Table
No.










DCF*
rem
pCi • cm"3- h





DCFcp



TOTAL -
Dose
rCDE 1
(rem)




TEDE
(rem)




                                                       8-18

-------
          PROBLEM lb-2: DOSE PROJECTION
                  TEDE AT 2 MILES

Using the same assumptions for the three radionuclides,
calculate the TEDE at 2 miles.

- Exposure duration = 3 hours

- Stability class = D

- Wind speed = 2 m/s

CDEcp =  DCFcp •  Xin =  DCFcp • (Q/u • XQ/Q • h)
                                                 8-19

-------
       PROBLEM I b 2:  FIND TEDE AT 2 MILES
           FORXe 133 I 131 AND Cs 134
  Step I
    X
     2mi
Xu .  0
0   tJ
               = 2AE-5
LIE+3
LIE-I
5.QE-2
Step2- X-h = Xin  (h = 3)
Step 3 - Xin
                   = TEDE
  DCFcp comes from Table
                                            8-20

-------
PROBLEM 2: DOSE PROJECTION USING
   SEPARATE PATHWAY DCFs

1 Assumptions:

   -  Time from shutdown to release:  2 hours

   -  Estimated release time: 3 hours

   -  Release height: Ground level

 - Stability is class D

   -  Wind speed is 2 m/s (4.5 mph).

                                                 8-21

-------
PROBLEM 2:  PROJECTED DOSE AS A FUNCTION OF
            PATHWAY
• Same source terms, meteorology, and exposure time as for
  problem  I.
• Same integrated air concentrations,
  Three separate exposure pathways,
                                                 8-22

-------
PROBLEM 2:  PROJECTED DOSE AS A FUNCTION OF
            PATHWAY (cont'd)
• External dose (EDE) from the plume
   (Table 5-3)

• Plume inhalation dose (CEDE)
   (Table 5-4)

• External dose (EDE) from deposited radionuclides (Table 5-5)
                                                  8-23

-------
               PROBLEM!: DOSE MODELS
 Dose  = DCF  •  X.  = DCF
      P        p    in         p
Q .
u
XJ
Q
•  (XQ/Q • Q/0) • h = X •  h = Xin




• For I-131: (2.4E-5)  • (17E-1 )/2 = 2.0E-6 Ci/m:
• 2.0E-6 Ci/m3 • 3h = 6.0E-6 (uCi • cm'3 • h)
  Calculate Xin and dose for each nuclide.
  Fill in matrixes (VG 8-25, 26, and 27).
h
                                                     8-24

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORK SHEET
Problem  2a :  Projected Dose at 2 Mile(s): From immersion  pathway
Nuclide(s)
& Prblm.
#2a
Xe-133
1-131
Cs-134






Xu/Q
@2 mi
(m-2)









Q
(Ci/s)









u
(mis)









X
@2mi
(pCi/cm3)









Exp.
time
(h)









xin
@2 mi
(jjCi • cm"3 • h)









DCF
Table
No.









DCF^
rem
pCi • cm'3- h



TOTAL -





Dose
( }
(rem)









                                                        8-25

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                        WORK SHEET
Problem  2b  : Projected Dose at 2 Mile(s): From inhalation   pathway
Nuclide(s)
& Prblm.
#2b

Xe-133
1-131
Cs- 1 34






Xu/Q
@2mi
(m-2)










Q
(Ci/s)










0
(m/s)










X
@2mi
(MCi/cm3)










Exp.
time
(h)










xin
@2mi
(pCi • cm"3 • h)










DCF
Table
No.










DCF^
rem
pCi • cm"3- h




TOTAL -





Dose
( )
(rem)










                                                       8-26

-------
        RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                        WORK SHEET
Problem 2c : Projected Dose at 2 Mile(s): From deposition   pathway
Nuclide(s)
& Prblm.
# 2c

Xe-133
1-131
Cs- 1 34






Xu/Q
@2mi
(m-2)










Q
(Ci/s)










Q
(m/s)










X
@ 2 mi
(MCi/cm3)










Exp.
time
(h)










xin
@2 mi
(|jCi • cm"3- h)










DCF
Table
No.










DCF^
rem
uCi • cm"3- h




TOTAL -





Dose
( v
(rem)










                                                        8-27

-------
          RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                        WORK SHEET
Problem #	2
The dose model is:  Dose = DCF •  Xin = DCF • (Q/u • XG/Q • h)
DOSE PROJECTION AT 2 MILES FOR INDIVIDUAL PATHWAYS
Nuclide
1-131
Cs- 1 34
Xe-133
Pathway
immersion
inhalation
deposition
DCF
rem
(pCi -cm*3- h)
2.2E+2
3.9E+4
I.3E+4
xin
(pCi • cm"3 • h)
6.0E-6
6.0E-6
6.0E-6
Dose
(rem)
I.3E-3
2.4E-I
8.0E-2
TEDE for 1-13 1 3.2E-I
immersion
inhalation
deposition
9.IE+2
5.6E+4
6.2E+3
I.8E-6
I.8E-6
I.8E-6
I.7E-3
I.OE-I
I.IE-2
TEDE for Cs- 134 I.IE-I
immersion
inhalation
deposition
20
0
0
6.0E-2
6.0E-2
6.0E-2
1.2
0
0
TEDE for Xe-133 1.2
TEDE for all radionudides combined
1.5
                                                     8-2

-------
            SESSION 9

  PROTECTIVE ACTION GUIDES FOR
    RELOCATION AND RETURN

              AND

DOSE LIMITS FOR RECOVERY WORKERS

-------
               THE "R" WORDS
                    (p. A-3)

Relocation: The removal or continued exclusion of
people (households) from contaminated areas to avoid
chronic radiation exposure.

Return: The reoccupation of areas cleared for
unrestricted residence or use.

Restricted zone: An area with controlled access from
which the population has been relocated.
                                                 9-1

-------
               THE "R" WORDS
                    (p. A-3)
                     (cont'd)

Reentry:  Temporary entry into a restricted zone
under controlled conditions.

Recovery: The process of reducing radiation exposure
rates and concentrations in the environment to
acceptable levels for unconditional occupancy or use.
                                                9-2

-------
           POTENTIAL TIME FRAME OF
       RESPONSE TO A NUCLEAR INCIDENT
  Refer to PAG Manual Page 7-5.
•  Times are estimates only.
•  Sequences may vary some.
                                            9-3

-------
            EXPOSURE PATHWAYS
                    (p. 4-2)

Pathways to be evaluated as basis for relocation
-  Whole body exposure to gamma radiation
-  Inhalation of resuspended materials

Minor pathways (no evaluation needed for reactor
accidents)
-  Beta skin exposure
-  Inadvertent ingestion of dirt
-  Refer to EPA 520/1-89-016
                                                9-4

-------
            ESTIMATED DOSE FROM MINOR
                 EXPOSURE PATHWAYS
Individual3
adult
child
adult or child
Exposure
Pathway
skinb
ingestionc
skinb
ingestionc
groundshine
First Year Dose (rem)
Soil
2.4
0.01
8.1
0.05
1.0
Pavement
8.4
O.I
14
0.5
1.0
aMaximum exposed individuals. Average exposure is about 1/3 to 1/6 lower.

blncludes beta dose from nearby surfaces and from material on the skin.

inadvertent ing stion of contaminat d dirt.
                                                            9-5

-------
        RELOCATION AND RETURN PAGS
                      (p. 4-4)
Projected Dose From
First Year Exposun

>2 rem TEDE
^100 rem DE skin
<2 rem TEDE
< 100 rem DE
      Protective Action

Establish restricted zone and
relocate the general
population.

Apply simple dose reduction
techniques to skin.
                                                9-6

-------
        RELOCATION AND RETURN PAGS
              (p. 4-4  4-5  E-13 & E-20)
                      (cont'd)

Additional guidance

-  0.5 rem in any year after the first
   5 rem in 50 years

Actual dose should be less  than projected dose

   Shielding
-  Mobility
-  Special dose reduction efforts
-  Refer to tables on pages E-13 and E-20
                                                    9-7

-------
                                                      PLUME TRAVEL
                                                        DIRECTION
LEGEND
 LJ
        1. PLUME DEPOSITION
        2.  AREA FHOM WHICH
                  TOM « EVACUATED.
        3.
A M
POPULATION a
         4   AREA FHOM VMMOH POPUUMHON O RELOCATED pESmCTEO ZONE).
                                                                                  9-8

-------
               GRADUAL RETURN
                   (p. 4-5 & 7-4)

Establishment of buffer zone

Gradual return

FEMA option to combine temporary relocation and gradual
return boundaries

-  Advantage - no early dose calculations

   Disadvantage - large relocation area
                - major public disruption
                                                  9-9

-------
       DOSE REDUCTION FOR RETURNEES
                    (p. 4-3)

Areas for priority

-  Dose in excess of 0.5  rem in I st year

-  Residences of pregnant women

Responsibility for actions
                                               9-10

-------
                  EXAMPLES OF
     S MPLE DOSE REDUCT ON TECHN QUES
             (pp.4-3, 7-6, E-13, &E-I9)

Scrub/flush/wipe hard surfaces.

Soak or plow soil.

Cut and remove grass clippings and other foliage.

Remove spots of soil where radioactivity has concentrated,

Disposal of contaminated materials
                                                 9-11

-------
     SIMPLE DOSE REDUCTION TECHNIQUES
             (pp.43, 76, E-I3,&E 19)
                     (cont'd)

Remove debris.

Spend more time in areas with lower contamination levels
(e.g., indoors).

Replace sandbox sand.

Pay special attention to child hygiene.
                                                 9-12

-------
      RAT ONALE - FOUR PR NC PLES
Acute health effects
Delayed health effects




Cost of avoiding risk




Risk - risk comparison
                                               9-13

-------
            FACTORS NOT NCLUDED  N
              THE RELOCAT ON PAGs
•   Physical and mental stress

•   Past exposures

•   Dose from ingestion

•   Dose from occupational exposure
                                                9-14

-------
                 COST ANALYSIS
                (pp. E-8, E-9, & E-10)
Assumptions:
-  Value of avoiding a statistical death is $400,000 to
   $7,000,000.
                                        *
-  Average daily cost of relocation is $27 - Refer to EPA
   520/1-89-015.

Where does the daily cost of relocation equal the
monetary value of average daily risk avoided?
                                                    9-15

-------
                10       11       10
                TIMt AFTBH ACCIOKMT 
-------
          PRINCIPLE
BASIS FOR SETTING PAG LEVELS
              (p. I -5)

                       STRATEGY
(I)  Avoid acute health effects.

(2)  Adequately protect against
    cancer and genetic effects
    under emergency conditions.
(3)  Optimize cost of protective
    action versus avoided dose.

(4)  Regardless of the above
    principles, the risk from a
    protective action should not
    itself exceed the risk from the
    dos  th t would be  void  d.
                      Stay below threshold dose.

                      Set PAG at this level unless
                      driven down by cost/risk
                      considerations (3), or up by
                      risk/risk considerations (4).

                      Use this principle only if the
                      the PAG value is driven down.

                      Use this principle only if the
                      PAG value is driven up.
                                                                           9-17

-------
   CONCLUSIONS ON APPROPRIATE VALUE
            FOR RELOCATION PAG
                   (p. E-18)

Principle on acute effects is not applicable.

Judgment of acceptable level of risk of delayed health
effects:
-  5 rem in 50 years
-  0.5 rem in any single year after the first

2 rem in the first year will meet the above criteria for
nuclear  power plant accidents.
                                               9-18

-------
   CONCLUS ONS ON APPROPR ATE VALUE
           FOR RELOCAT ON PAG
                  (p. E-18)
                    (cont'd)

Cost will not drive the first year dose below 2 rem,
Risk from relocation is assumed to be the same as for
evacuation (i.e., equivalent to the risk from about 30
mrem).
                                             9-19

-------
   DOSE LIMITS FOR RECOVERY WORKERS
            (pp.46, 7  17, &E 19)

Same as for occupationally exposed workers

-  TEDE                         5 rem/y
-  CDE to any organ               50 rem/y

-  One tenth these values to persons under
   age 18

-  TEDE to declared pregnant
   women                       0.5 rem/9mo
                                           9-20

-------
              SESSION 10
DATA COLLECTION AND DOSE PROJECTION
                FOR
  RELOCATION AND RETURN DECISIONS

-------
IMPLEMENTING PAGS FOR THE INTERMEDIATE
                  PHASE

Relocation

Reentry

Return

Early Decontamination

Ingestion of Food and Water
-   Independent decision
                                           10-1


-------
               OVERV EW OF
         MPLEMENTAT ON PROCESS

Collect environmental samples.

Analyze samples.

Calculate
-  Exposure rates and projected dose.
-  Accident specific DCFs.
-  Derived response  level.

Make gamma exposure rate measurements.
                                             10-2

-------
                OVERV EW OF
           MPLEMENTAT ON PROCESS
                     (cont'd)

Take air samples and calculate projected dose from
inhalation of resuspended materials.

Identify the boundary of the restricted zone.

Relocate the population.

Identify the buffer zones.

Implement gradual return.
                                                10-3

-------
     SAMPLE COLLECTION AND ANALYSIS

Purpose of samples
-  Dose projection
-  Evaluation of variation in mix by area

Nature of samples

Locations of samples
-  Based on exposure rate
-  Priorities
-  Terrain

Types of analyses
                                                10-4

-------
          ALTERNATIVE METHODS
           FOR DOSE PROJECTION

METHOD ONE - Sample from each area of interest

-  Known size of area in each sample

-  Use data from each sample analysis to project dose.

-  Plot projected doses on map to identify location of
   boundary to the restricted zone.
                                             10-5

-------
        ALTERNATIVE METHODS FOR
             DOSE PROJECTION
                    (cont'd)

METHOD TWO - Take a few samples from several
areas.

Determine whether the radionuclide mix is reasonably
constant or predictable. If so:

-  Calculate a time-dependent derived response level
   (DRL^) corresponding to the PAG.

-  Use the DRL^ to identify the restricted zone.
                                             10-6

-------
     CONS DERAT ON OF METHOD ONE

Requires a arge number of
-  samples
-  laboratory analyses
-  dose projections

May yield wrong result for other than flat terrain

Only method available if radionuclide mix is neither
constant nor predictable
                                               10-7

-------
     CONSIDERATION OF METHOD TWO
Not useful for an inconsistent mix of radionuclides.

Greatly reduces the sampling and laboratory effort.

Results are independent of terrain type or presence of
contaminated foliage.

Inaccuracies due to non-representative samples cancel.
                                                10-8

-------
EXAMPLE CALCULATION OF EXPOSURE RATE
            - Method One -
Radionuclide
Cs-134
1-131
Concentration
pCi/m2
2E+7
3E+7
Initial exposure Rate @ 1 m
(mR/h per pCi/m2)
(table 7-1 or 7-2)


Total:
Exposure Rate @ 1 m
(mR/h)



                                    10-9

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Year One
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)


TOTAL
Projected
Dose
(mrem)



                                     10-10

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Year Two
Radionuclide
Cs-134
1-131
Concentration(
pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
(mrem/pCi/m2)
. (Table 7-2)


TOTAL
Projected
Dose
(mrem)
.


                                       10-11

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
Integrated Dose - Zero to 50 Years
Radionuclide
Cs- 1 34
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)


TOTAL
Projected
Dose
(mrem)



No Weathering
DCF
. (mrem/pCi/m2)
(Table 7-2)


TOTAL
Projected
Dose
(mrem)



                                       10-12

-------
                  METHOD 2
Calculate an accident-specific dose conversion factor
(DCFas).

-  This factor is time dependent.
Use DCFas to calculate a time-dependent derived
response level (DRL^) in  mR/h corresponding to the
PAG.
                                               10-13

-------
 CALCULATION OF ACCIDENT SPECIFIC DCF
                  Method 2
35
          =  mrem per yr- 1 , /r-2, or 0 to 50 yr
              Exposure Rate @ I m (mRlh)
Assume weathering and results from VGs 9, 10, II,
and 12, and calculate:
   Year one DCFas =
   Year two DCFas =
   Zero to 50 year DCFas =
                                           10-14

-------
 CALCULATION OF ACCIDENT SPECIFIC DRL
                 Method 2
                      DCF
                          as
For the previous example (weathering included):
  Year one DRLas =
  Year two DRLas =
              do
   Zero to 50 year DRLas =
                                          10-15

-------
  DCF FOR PROJECTED  EXTERNAL GAMMA DOSE
                        / J
                         0



    DCF = DS pi1"*—
                 I     ^H   "^


                                                                 D

= dose rate per unit deposit (mrem/yr per pCi/m2) (data in DOE EH 0070)


Sf   = protection factor for shielding and partial occupancy (assumed to be unity)


AR   = radioactive decay constant (yr"1)


A2   = assumed weathering decay constant for 63% of the radionuclide =1.13 yr"1


A3   = assumed weathering decay constant for 37% of the radionuclide = 7.48E-3 yr"1


t   = time of exposure (yr)
                                                                 10-16

-------
    CALCULATION OF DOSE FROM INHALATION
        OF RESUSPENDED MATERIALS (CEDE)
                 (Table 7-4, p. 7-16)

                   H50 = I x DCF
WHERE:
   Hso = CEDE for 50 y from intake of nuclides

   I   = total intake (pCi)

   DCF  = dose per unit intake for the radionuclide
          (rem per pCi)
           -   Data are from EPA FGR No. 11
           -   Convert to appropriate units
                                               10-17

-------
             TOTAL  NTAKEFROM  NHALATON
                 OF RESUSPENDED MATERIAL
WHERE:
B
            / = BC
                   o
total intake in I year (pCi)

breathing rate, assumed to be I.05E+4 m3/yr

initial air concentration of the resuspended radionuclide (pCi/m3)

radioactive decay constant (yr"1)

assumed weathering decay constant for 63% of the radionuclide =1.13 yr"1

assumed weathering decay constant for 37% of the radionuclide = 7.48E-3 yr"1

time of exposure (yr)
                                                                     10-18

-------
 WEATHERING OF THE RESUSPENSION FACTOR

EPA assumes gamma weathering for resuspension.

Empirical data for alpha emitters shows much faster
reduction.

Refer to:
-  WASH-1400 Appendix VI page E-13 for a time
   dependent model.

-  IAEA Safety  Series 81,1986, page 62 for plot of the
   resuspension factor as a function of time and of the
   integral.
                                               10-19

-------
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ ] yes [ ] no
Sample
Radio-
Nuclide
Cs-134
1-131




location Analysis date

Air
Concentration
(pCi/m3)
1200
420




Yr. 1 DCF
(mrem per
pCi/m3)





TOTAL-
Dose From
Yr. 1 Exp.
(mrem)






Yr. 2 DCF
(mrem per
pCi/m3)





TOTAL-
Dose From
Yr. 2 Exp.
(mrem)

.




10-20

-------
           SESS ON
    DOSE PROJECTION PROBLEMS
              FOR
RELOCATION AND RETURN DECISIONS

-------
        PROBLEM I - A:  DERIVATION OF AN
            ACCIDENT-SPECIFIC DOSE
            CONVERSION FACTOR (I)
                 -Method ONE-
GIVEN:
•  A surface soil sample is analyzed and is found to
   contain the following concentrations (pCi / m2):
                                     *
     Zr-95    7.4 E+6       Cs-134 I2.0E+6
     Ru-103   3.1 E+6       Cs-137  1.2 E+6
     1-131     4.1 E+6       Ba-140  6.2 E+6

•  Radioactive decay and weathering will occur.
                                               11-1

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ x] Y ar 1 [ ] Ye r 2 [ ] 50 Y rs
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs- 1 34
Cs- 1 37
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3.IE+06
4. 1 E+06
1 .2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)






TOTAL-
Calculated
DOSE
(mrem)







Combined DCF
             as
mrem per mR/h
(date_
                                                                    11-2

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ X] Year 2 [ ] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs- 1 34
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3.IE+06
4. 1 E+06
1 .2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

.




TOTAL-
Calculated
DOSE
(mrem)


•




Combin d DCF
           as
mrem p r mR/h
(dt
                                                              11-3

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ ] Year 2 [ X] 50 Years
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4E+06
3. 1 E+06
4. 1 E+06
I.2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)






TOTAL-
Calculated
DOSE
(mrem )







Combined DCF
            as
mrem per mR/h
(date_
                                                                   11-4

-------
        PROBLEM I  - B:  DERIVATION OF AN
            ACCIDENT-SPECIFIC DOSE
            CONVERSION FACTOR (I)
                 - Method TWO -
GIVEN:
•  A surface soil sample is analyzed and is found to
   contain the following activities (uCi / sample):

     Zr-95    7.4         Cs-134  12
     Ru-103   3.1         Cs-137  1.2
     1-131     4.1         Ba-140  6.2

•  Radioactive decay and weathering will occur.
                                               11-5

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ x] Y r 1 [ ] Ye r 2 [ ] 50 Y ars
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru- 1 03
1-131
Cs-134
Cs-137
Ba- 1 40

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3. 1 E+06
4. 1 E+06
I.2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)

.

•


TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)







Combin d DCF,
_mr m p r mR/h
(dat
                                        11-6

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ ] Year 1 [ X] Y ar 2 [ ] 50 Y rs
Sample location Weathering? [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs- 1 34
Cs- 1 37
Ba-140

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3. 1 E+06
4. 1 E+06
1 .2E+07
I.2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-*
Nominal
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pG/m'l

•




TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)







Combin d DCFa
_mr m p r mR/h
(d te.
                                        11-7

-------
CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFJ
For? [ ] Year 1 [ ] Year 2 [ X] 50 Years
Sample location Weathering' [ ] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/sample)
7.4E+06
3.IE+06
4. 1 E+06
1 .2E+07
1 .2E+06
6.2E+06

Initial Exp.
Rate @ 1 m
(mR/h per
pCi/m2)






TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h @ 1 m)







Integrated
Dose
(mrem per
pCi/m2)



•


TOTAL-
Nominal
Calculated
DOSE
(mrem @ 1 m)


•




Combin d DCF,
_mr m p r mR/h
(dat
                                         11-8

-------
     PROBLEM 2: DERIVED RESPONSE LEVELS

Using results from Problem I, calculate time-dependent
derived response levels (DRL^) corresponding to:

-  year I

-  year 2

-  50 years
Interpret the results.
                                                 11-9

-------
                   PROBLEM 3
                PROJECTED DOSE

Field teams report the following exposure rates:
   Location A       3 mR/h
   Location B       10 mR/h
   Location C      30 mR/h

Assume the radionuclide mix from Problem I.

What is the projected dose from gamma radiation at each
location for each of the three time periods?
                                                11-10

-------
PROBLEM 3: PROJECTED DOSE
           (cont'd)
Location
A
B
C
Meter
Reading
(mR/hr)
3
10
30
Projected
dose
year one
(rem)




DCF for year one (rem per mR/h)
DCF for year two (rem per mR/h)
DCF for 0 to 50 y (r m p r mR/h)
Projected
dose
year two
(rem)




3.3
1.2
8.2
Projected
dose
0 to 50 y
(rem)







                                    11-11

-------
        PROBLEM 4: INHALATION DOSE
     DUE TO RESUSPENDED MATERIALS (I)

Analysis of an air sample collected at location "A"  where
the exposure rate is 3 mR/h yields activities as follows
(pCi/m3):

   Zr-95   760     Cs-134   1200
   Ru-103  320     Cs-137   120
   1-131    420     Ba-140   630
Weathering is assumed.
                                              11-12

-------
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
Sample location A Analysis date
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140


Air
Concentration
(pCi/m3)
760
320
420
1200
120
630


Yr. 1 DCF
(mrem per
PCi/m3)







TOTAL-
Dose From
Yr. 1 Exp.
(mrem)








Yr. 2 DCF
(mrem per
pCi/m3)







TOTAL-
Dose From
Yr. 2 Exp.
(mrem)


•





11-13

-------

-------
                        SESSION 12
          COURSE REVIEW AND WRAP-UP
Ritchey C. Lyman
Office of Radiation and Indoor Air
Phone (202) 564-9363
Fax: (202) 565-2037
lyman.ritchey@epa.gov

-------
- PROBLEM SOLUTIONS -

-------
                          PROBLEM SOLUTION
Problem Emergency worker    Projected Dose at Location A from inhalation

Nuclide(s)
Ce-I4l
Ba-140
Cs-134


Air
Concentration
(X)
(uCi/cm3)
1 .OE-05
LOE-04
1. OE-05


Projected.
Exposure
Time
(h)
1
1
1


Integrated Air
Concentration
(uCi • cm"3 • h)
0.00001
0.000 1
0.00001


DCF from
Table 5-4
(rem per
uCi • cm"3 • h)
I.IE+04
4.5E+03
5.6E+04
Totals >
Inhalation
Committed
Effective Dose
Equivalent
(CEDE)
(rem)
O.I I
0.45
0.56
1.12
                                                                      6-22a

-------
      EXAMPLE OF COMBINED PATHWAYS
                 SOLUTION

Nuclide selected Co-60

Pathway
External
Inhalation
Ground Shine
Table
5-3
5-4
5-5
Summation
DCF
(rem per uCi • cm "3 • h)
I.5E+3
2.6E+5
8.9E+3

xin
(uCi ; cm"3 • h)
1
1
1

Dose
(rem)
I.5E+3
2.6E+5
8.9E+3
2.6E+5

Combined
5-1
2.7E+5
1
2.7E+5
                                        7-22a

-------
         RAD AT ON ACC DENT ASSESSMENT COURSE
                         WORKSHEET

Problem I a-1 & Ib-l  : Projected Dose at I   Mile(s): From thyroid & combined  pathway
Nuclide(s)
& Prblm.
# la-l
1-131


Nuclide
# Ib-l
Xe-133
1-131
Cs-134

Xu/Q
@J_mi
(m2)
7.0E-5




7.0E-5
7.0E-5
7.0E-5

Q
(Ci/s)
0.17




1700
0.17
0.05

u
(m/s)
2




2
2
2

X
@J_mi
(MCi/cm3)
6.0E-6




6.0E-2
6.0E-6
I.8E-6

Exp.
time
(h)
3




3
3
3

xin
@J_mi
(MCi-cm-3-h)
I.8E-5

•


I.8E-I
I.8E-5
5.25E-5

DCF
Table
No.
5-2




5-1
5-1
5-1

DCF^
rem
MCi • cm"3' h
I.3E+6



DCFcp
2.0E+I
5.3E+4
6.3E+4
TOTAL -
Dose
(CDE)
(rem)
23


TEDE
(rem)
3.6
0.95
0.33
4.9
                                                              8-6a

-------
     RAD AT ON ACC DENT ASSESSMENT COURSE
                     WORK SHEET

Problem la-2 & lb-2  : Projected Dose at 2  Mile(s): From thyroid & combined  pathway
Nuclide(s)
& Prblm.
# la-2
1-131


Nuclides
# lb-2
Xe-133
1-131
Cs-134

Xu/Q
@_2_mi
(m-2)
2.4E-5




2.4E-5
2.4E-5
2.4E-5

Q
(Ci/s)
0.17




1700
0.17
0.05

u
(m/s)
2




2
2
2

X
@2mi
(pCi/cm3)
2.0E-6




2.0E-2
2.0E-6
6.0E-7

Exp
time
(h)
3




3
3
3

xin
@_2_mi
(pCi • cm"3- h)
6.0E-6




6.0E-2
6.0E-6
I.8E-6

DCF
Table
No.
5-2




5-1
5-1
5-1

DCF*
rem
(jCi • cm"3- h
I.3E+6



DCFcp
2.0E+I
5.3E+4
6.3E+4
TOTAL -
Dose
(CDE)
(rem)
8

,
TEDE
(rem)
1.2
0.32
0.12
1.6
                                                     8-18a

-------
        RAD OLOG CAL ACC DENT ASSESSMENT COURSE
                         WORK SHEET
Problem   2a  Projected Dose at 2 Mile(s): From immersion
pathway
Nuclide(s)
& Prblm.
# 2
Xe-133
1-131
Cs-134





XQ/Q
@2mi
(m-2)
2.4E-5
2.4E-5
2.4E-5





Q
(Ci/s)
1700
0.17
0.05





U
(m/s)
2
2
2





X
@2mi
(pCi/cm3)
2.0E-2
2.0E-6
6.0E-7





Exp.
time
(h)
3
3
3





xin
@2 mi
(pCi • cm"3- h)
6.0E-2
6.0E-6
1 .8E-6





DCF
Table
No.
5-3
5-3
5-3





DCFim
rem
pCi • cm"3- h
20
2.2E+2
9.IE+2
TOTAL-




Dose
(EDE)
(rem)
1.2
I.3E-3
IJE-3
1.2




                                                            8-25a

-------
       RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                        WORK SHEET
Problem  2b  : Projected Dose at 2 Mile(s): From  inhalation pathway
Nuclide(s)
& Prblm.
# 2b
Xe-133
1-131
Cs-!34




XQ/Q
@_2_mi
(m-2)
2.4E-5
2.4E-5
2.4E-5




Q
(Ci/s)
1700
0.17
0.05




0
(m/s)
2
2
2




X
@2mi
(pCi/cm3)
2.0E-2
2.0E-6
6.0E-7




Exp.
time
(h)
3
3
3




xin
@_2_mi
(|jCi • cm"3- h)
6.0E-2
6.0E-6
1 .8E-6




DCF
Table
No.
5-4
5-4
5-4




DCFinh
rem
pCi • cm"3- h
0
3.9E+4
5.6E+4
TOTAL-



Dose
(CEDE)
(rem)
0
2.4E-I
I.OE-I
3.4E- 1



                                                           8-26a

-------
     RADIOLOGICAL ACCIDENT ASSESSMENT COURSE
                      WORK SHEET

Problem_2c_: Projected Dose at 2 Mile(s): From ground shine pathway
Nuclide(s)
& Prblm.
# 2c
Xe-133
1-131
Cs-134




Xii/Q
@2mi
(m-2)
2.4E-5
2.4E-5
2.4E-5




Q
(Ci/s)
1700
0.17
0.05




u
(m/s)
2
2
2




X
@_2_mi
(nCi/cm3)
2.0E-2
2.0E-6
6.0E-7




Exp.
time
(h)
3
3
3




xin
@_2_mi
(nCi • cm'3- h)
6.0E-2
6.0E-6
1.8E-6




DCF
Table
No.
5.5
5.5
5.5




DCFdep
rem
jiCi • cm"3- h
0
1.3E+4
6.2E+3
TOTAL -



Dose
(EDE)
(rem)
0
8.0E-2
1.1E-2
0.09



                                                       8-27a

-------
EXAMPLE CALCULAT ON OF EXPOSURE RATE
             - M thod On -

              SOLUTION
Radionuclide
Cs-134
1-131
Concentration
pCi/m2
2E+7
3E+7
Initial exposure Rate @ 1m
(mR/h per pCi/m2)
(table 7-1 or 7-2)
2.6E-8
6.6E-9
Total:
Exposure Rate @ 1m
(mR/h)
0.52
0,20
0.72
                                                10-9a

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
             - Method One -
              SOLUTION
Integrated Dose - Year One
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
l.OE-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
2000
39
2039
No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)
1.3E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
2600
39
2639
                                     10-10a

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
              - Method One -

               SOLUTION
Integrated Dose - Year Two
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
4.7E-5
0
TOTAL
Projected
Dose
(mrem)
940
0
940
No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)
9.6E-5
0
TOTAL
Projected
Dose
(mrem)
1900
0
1900
                                                  10-lla

-------
EXAMPLE CALCULATION OF PROJECTED DOSE
              - Method One -

              SOLUTION
Integrated Dose - Zero to 50 Years
Radionuclide
Cs-134
1-131
Concentration
(pCi/m2)
2E+7
3E+7
Weathering
DCF
(mrem/pCi/m2)
(Table 7-1)
2.4E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
4800
39
4839
No Weathering
DCF
(mrem/pCi/m2)
(Table 7-2)
4.7E-4
1.3E-6
TOTAL
Projected
Dose
(mrem)
9400
39
9439
                                   10-12a

-------
CALCULATION OF ACCIDENT SPECIFIC DCF

                   Method 2



                  SOLUTION
          mrem per yr-1,  yr-2, or 0 to 50 yr
          	
              Exposure Kate @ 1m (mR/h)
 Assume weathering and results from VGs 9,10,11, and 12, and

   calculate:



 -  Year one DCFas = 2039 mrem/0.72 mR/h = 2832 mrem/niR/h



 -  Year two DCFas = 940 mrem/0.72 mR/h = 1305 mrem/mR/h



 -  0 to 50 year DCFas = 4839  rem/0.72 R/h = 6720


                                              10-14a

-------
     CALCULATION OF ACCIDENT SPECIFIC DRL
                     - Method 2 -

                     SOLUTION
                  DRL
      PAG
td ~  DCF
                               as
For the previous example (weathering included):
 Year one DRLas = 2000 mrem •*- 2832 mrem/mR/h = 0.71 mR/h
  Year two DRLas = 500 mrem -5-1305 mrem/mR/h = 0.38 mR/h
- Z ro to 50 y  r DRLas = 5000 + 6720 = 0.74 mR/h
                                                   10-15a

-------
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
Sample
Radio-
Nuclide
Cs-134
1-131




location Analysis date

Air
Concentration
(pCi/m3)
1200
420




Yr. 1 DCF
(mrem per
pCi/m3)
3.1E-1
1.1E-2



TOTAL-
Dose From
Yr. 1 Exp.
(mrem)
370
4.6



375
Yr. 2 DCF
(mrem per
pCi/m3)
1.5E-1
0



TOTAL-
Dose From
Yr. 2 Exp.
(mrem)
180
0



180
10-20 a

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Problem 1: Derivation of an Accident-Specific Dose Conversion Factor

                          SOLUTION

  Refer to Table 7-1 and, as example, Table 7-3.

  Unit of the DCF for the projected external gamma dose is:
   xx mrem for each mR/h measured at the beginning of the period

  For year one:
              1.6E+03 mrem per 4.9E-01 mR/h yields
            3.3e+3 mrem per mR/h or 3.3 rem per mR/h

  For 0-50 years:
                 4.0E-03 mrem per 4.9E-01 mR/h
            8.2E+3 mrem per mR/h or 8.2 rem per mR/h
                                                             ll-la

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [xIYearl [ I Year 2 [ ] 50 Years
Sample location A Weathering? [ x] yes [ ] no
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
Integrated
Dose
(mrem per
pCi/m2)
3.3e-05
7.1e-06
1.3e-06
l.Oe-04
4.5e-05
l.le-05
TOTAL-
Calculated
DOSE
(mrem)
2.4e+02
2.2e+01
5.3e+00
1.2e+03
5.4e+01
6.8e+01
1.6e+03
Co  bined DCFas _3.3 e+03_ re  per  R/h
(date_
                                                                     ll-2a

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ JYearl [x] Year 2 [ ] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
Ru-103
M31
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

n A Weathering

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
9 [x]yes []
Integrated
Dose
(mrem per
pCi/m2)
4.0e-07
O.Oe+00
O.Oe+00
4.7e-05
2.9e-05
O.Oe+00
TOTAL-
no
Calculated
DOSE
(mrem)
3.0e+00
O.Oe+00
O.Oe+00
5.6e+02
3.5e+01
O.Oe+00
6.0e+02
Co  binedDCFas___1.2e+03_  re  per
R/h    (date.
                                                                         ll-3a

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For'' [ JYearl [ ] Year 2 [x] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering'

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-

Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.4e-05
7.1e-06
1.3e-06
2.4e-04
6.1e-04
l.le-05
TOTAL-
Calculated
DOSE
(mrem)
2.5e+02
2.2e+01
5.3e+00
2.9e+03
7.3e+02
6.8e+01
4.0e+03
Co  bined DCFas _8.2 e+03_  re  per  R/h
(date
                                                                    11-4 a

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [xJYearl [ ] Year 2 [ ] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering*

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.3e-05
7.1e-06
1.3e-06
l.Oe-04
4.5e-05
l.le-05
TOTAL-
Nominal
Calculated
DOSE
(mrem)
2.4e+02
2.2e+01
5.3e+00
1.2e+03
5.4e+01
6.8e+01
1.6e+03
Co  bined DCFas _3.3 e+03_  re  per  R/h
(date_
                                                                        ll-6a

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For'' [ JYearl [x|Year2 [ ] 50 Years
Sample locatioi
Radio-
Nuclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-

Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [x]yes [
Integrated
Dose
(mrem per
pCi/m2)
4.0e-07
O.Oe+00
O.Oe+00
4.7e-05
2.9e-05
O.Oe+00
TOTAL-
no
Nominal
Calculated
DOSE
(mrem)
3.0e+00
O.Oe-l-00
O.Oe+00
5.6e+02
3.5e+01
O.Oe+00
6.0e+02
Combined DCFas _1.2 e+03_  re  per  R/h    (date.
                                                                     ll-7a

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CALCULATION OF ACCIDENT-SPECIFIC DCF (DCFas)
For? [ JYearl ( J Year 2 [x] 50 Years
Sample locatioi
Radio-
iS uclide
Zr-95
Ru-103
1-131
Cs-134
Cs-137
Ba-140

Measured
Ground
Concentration
(pCi/m2)
7.4e+06
3.1e+06
4.1e+06
1.2e+07
1.2e+06
6.2e+06

i A Weathering*

Initial Exp.
Rate @ 1m
(mR/h per
pCi/m2)
1.2e-08
8.2e-09
6.6e-09
2.6e-08
l.Oe-08
3.2e-09
TOTAL-
Nominal
Calculated
Exp. Rate
(mR/h@lm)
8.9e-02
2.5e-02
2.7e-02
3.1e-01
1.2e-02
2.0e-02
4.9e-01
? [ x] yes [ ] no
Integrated
Dose
(mrem per
pCi/m2)
3.4e-05
7.1e-06
1.3e-06
2.4e-04
6.1e-04
l.le-05
TOTAL-
Nominal
Calculated
DOSE
(mrem)
2.5e+02
2.2e+01
5.3e-i-00
2.9e+03
7.3e+02
6.8e+01
4.0e+03
Co  bined DCFas _8.2 e+03_  re   per  R/h
(date.
                                                                    11-8 a

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                      Problem 2: Derived Response Levels

                                  SOLUTION

•   A time-dependent derived response level (DRLtd) is the meter reading (mR/h (a), 1m)
    which, at the time of measurement, corresponds to either the year 1, year 2, or 0-50
    year dose.

•   For year one, a meter reading of 1 mR/h at 1 meter above the ground indicates an
    external gamma radiation dose of 3.3 rem during the first year. Therefore, the
    DCF (rem per mR/h) is 3.3 rem per mR/h.

•   A meter reading of 2.0/3.3 or about 0.6 mR/h, would indicate that the first year dose
    would be 2 rem or greater.

•   The DRLtd for year 1 is 0.6 mR/h.

    The DRLtd for year 2 is 0.5/1.2 or about 0.4 mR/h.

    The DRL for year 0-50 is 5.0/8.2 or about 0.61 mR/h.
                                                                           ll-9a

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                 Proble  2: Derived Response Levels
                          SOLUTION
                           (CO tfd)

Table 4-1: Protective Action Guides for Exposure to Deposited
Radioactivity During the Intermediate Phase of a Nuclear Incident

    Relocate if projected dose is greater than 2 rem.

    Projected dose includes external gamma radiation dose and the
    committed effective dose equivalent from inhalation during the
    first year.

    Beta skin dose may be up to 50 times higher.

Persons in areas with meter readings above 0.6 mR/h should be
r locat  d.

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Probl m 3 Projected Dos
      SOLUTION
Location
A
B
C
Meter
Reading
(mR/hr)
3
10
30
Projected
Dose
year one
(rem)
9.9
33
99
DCF for year 1 (rem per mR/h)
DCF for year 2 (rem per mR/h)
DCF for 0 to 50 y (rem per mR/h)
Projected
Dose
year two
(rem)
3.6
12
36
3.3
1.2
8.2
Projected
Dose
0 toSOy
(rem)
24.6
82
246



                                        ll-lla

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PROBLEM 3: PROJECTED DOSE
           (cont'd)
Location
A
B
C
Meter
Reading
(mR/hr)
3
10
30
Projected
dose
year one
(rem)




DCF for year one (rem per mR/h)
DCF for year two (rem per mR/h)
DCF for 0 to 50 y (rem per mR/h)
Projected
dose
year two
(rem)




3.3
1.2
8.2
Projected
dose
0 to 50 y
(rem)







                                    11-11

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       PROBLEM 4:  NHALATONDOSE
     DUE TO RESUSPENDED MATERIALS ( )

Analysis of an air sample collected at location "A"  where
the exposure rate is 3 mR/h yields activities  as follows
(pCi/m3):

   Zr-95    760     Cs-134   1200
   Ru-103  320     Cs-137   120
   1-131    420     Ba-140   630
Weathering is assumed.
                                              11-12

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Problem 4: Inhalation Dose (CEDE)
          SOLUTION
CALCULATION OF INHALATION DOSE (CEDE)
FROM RESUSPENDED MATERIALS
Includes weathering? [ x ] yes [ ] no
Si
Radio-
IS uclide
Zr-95
Ru-103
M31
Cs-134
Cs-137
Ba-140

imple location A Analysis date

Air
Concentration
(pCi/m3)
760
320
420
1200
120
630

Yr. 1 DCF
(nirem per
pCi/m3)
6.5e-02
1.3e-02
l.le-02
3.1e-01
2.5e-01
4.4e-03
TOTAL-
Dose From
Yr. 1 Exp.
(mrem)
4.9e+01
4.2e+00
4.6e+00
3.7e+02
3.0e+01
2.8e+00
4.6e+02
Yr. 2 DCF
(mrem per
pCi/m3)
•


1.5e-01
1.4e-01

TOTAL-
Dose From
Yr. 2 Exp.
(mrem)
O.Oe+00
O.Oe+00
O.Oe+00
1.8e+02
1.7e+01
O.Oe+00
2.0e+02

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                P  blew 4: Inhalation Do   (C D  )
                          SOLUTION
                            (eont'd)

•  Year one CEDE - 4.6E+02 mrem or 0.46 rem

•  Year two CEDE - 2.0E+02 mrem or 0.20 rem

•  Year one EDE - 9.9 rem (see problem 3)

•  Year one TEDE - 9.9 + 0.5 = 10.4 rem

•  Year two EDE - 3.6 rem (see problem 3)

•  Year two TEDE - 3.6 + 0.20 = 3.8 rem

•   Normally the lung clearance class and the particle size are not known.
   Ass  me the most co  servative co ditio  .

-------