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Existing Situations: Public Dose Limit and Optimization Through the Use of Reference Levels Existing Situations: Public Dose Limit and Optimization Through the Use of Reference Levels

Existing Situations: Public Dose Limit and Optimization Through the Use of Reference Levels - PowerPoint Presentation

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Existing Situations: Public Dose Limit and Optimization Through the Use of Reference Levels - PPT Presentation

Philip Egidi US Environmental Protection Agency Office of Radiation and Indoor Air LowLevel Waste Forum Alexandria VA October 17 2017 Usual Disclaimers Apply This presentation is the opinion of the author only and does not represent EPA policy regulation or position ID: 658064

dose 2017 msv october 2017 dose october msv icrp situations exposure level reference existing radiation public tenorm report optimization

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Slide1

Existing Situations: Public Dose Limit and Optimization Through the Use of Reference Levels

Philip Egidi

U.S. Environmental Protection Agency

Office of Radiation and Indoor Air

Low-Level Waste Forum

Alexandria, VA

October 17, 2017Slide2

Usual Disclaimers Apply…

This presentation is the opinion of the author only and does not represent EPA policy, regulation, or position.

October 17, 2017

2Slide3

Premise

Radiation protection is based on fundamental principles, based on science, derived over many decades at the international level.

There are three basic principles that form the basis for regulation and control of radioactivity:

Limitation

Justification

Optimization

3

October 17, 2017Slide4

Hierarchy of organizations:

Science forms the basis for recommendations

UNSCEAR

ICRP

IAEA

NAS

NCRP

ISCORSFEDERAL AGENCIESTRIBESCRCPDSTATES

COMPACTS

Source:

Lazo

2015/NEA

4

October 17, 2017Slide5

Inter-Agency Steering Committee on Radiation Standards

Technical staff meet semi-annually (at least) with the purpose of harmonizing and being consistent among agencies in their approach to radiation protection

5

October 17, 2017Slide6

Policy is Not Based on Science Alone

Source: Mossman 1999

6

October 17, 2017Slide7

ICRP 103 Framework

“The Recommendations of the International Commission on Radiological Protection” ICRP Report 103

Published in 2007

Replaced Report 60, published in 1990

Replaced Report 26/30, published in 1977

Many US Regulations (e.g., NRC 10 CFR 20) based on ICRP 26/30 dosimetry

Some DOE and EPA criteria based on ICRP Report 60

New dose coefficients from ICRP 103 in process

7

October 17, 2017Slide8

ICRP 103 changes

ICRP 60 (1990) based on activities that

increased

exposure (

practices

) and activities that

reduced

exposure (interventions)ICRP 103 (2007) based on

planned, existing and emergency situationsAll exposures, including those from (TE)NORM, are within the scope of the system.

The principles of

justification

and

optimization

apply universally to all exposures resulting from either planned, emergency or existing situations.

Limitation applies only to planned situations.

8

October 17, 2017Slide9

Optimization

ICRP recommends

optimization

(ALARA) as the

primary tool

for radiation protection

Uses

dose constraints or reference levels set

within bands of doses Bands of dose are based on multiples of

1

mSv

(100 mrem)

, being the approximate level of annual global per caput radiation exposure from natural sources (excluding exposures from radon.)

Optimization applied below the upper limit of the band

Not an enforceable dose limit

9

October 17, 2017Slide10

Planned and existing situations

ICRP 103 applies to all exposures to ionizing radiation from any source, regardless of size or origin.

For (TE)NORM, either the

source

of the exposure or the

pathways

leading to doses received by individuals can be

controlled by some

reasonable means, or Report 103 is not applicable. Planned situations, such as for licensed activities:

Use a

dose limit

Existing situations

, such as at NORM/TENORM industries:

Use a

reference level

10

October 17, 2017Slide11

Source: Lecompte 2013

Existing Situations vs Planned Situations

11

October 17, 2017Slide12

Existing Exposure Situations

A situation that already exists when a decision on control has to be taken, including natural background radiation and residues from past practices that were operated outside the Commission’s recommendations

NORM is an existing exposure situation (at least at first).

Reference level

In existing exposure situations, this represents the level of dose or risk, above which it is judged to be inappropriate to plan to allow exposures to occur, and below which optimization of protection should be implemented. The chosen value for a reference level will depend upon prevailing circumstances of the exposure under consideration.

NO DOSE LIMIT FOR EXISTING SITUATIONS…

12

October 17, 2017Slide13

Reference Level Implementation

Reference levels for public exposure (as applies to TENORM)

Reference levels expressed in effective doses shall be set in the range of 1 to 20

mSv

(

100

mrem

to 2 rem) per year for existing exposure situations and 20 to 100 mSv

(2 to 10 rem)(acute or annual) for emergency exposure situations. …(b) a reference level below 1

mSv

(

100

mrem

) per year may be set, where appropriate, in an existing exposure situation for specific source-related exposures or pathways of exposure.

…The reference levels set shall take account of the features of prevailing situations as well as societal criteria… …for exposures below or equal to 1 mSv (

100

mrem

) per year, general information on the level of exposure, without specific consideration of individual exposures…

13

October 17, 2017Slide14

ICRP 103 Dose limits

Public dose limit for planned situations is 1

mSv

/y above background

Effective dose

Exemption level for NORM isotopes:

1

kBq/kg (~27 pCi/g)Radon evaluated separately (ICRP 126, 2014)

There are other ICRP limits but will not discuss for brevity…

14

October 17, 2017Slide15

ICRP Report 126 on Radon

The Commission recommends 300 Bq/m

3

(8 pCi/L) as the upper value of the derived reference level for radon gas in dwellings.

This equates to ~12mSv/y (1.2 rem)

Derived reference levels relate to the annual mean concentration of radon in a building or location

The Commission recommended a detriment-adjusted nominal risk coefficient for lung cancer in a mixed adult population of non-smokers and smokers of 8x10

-10 per Bq/h/m3 for exposure to radon-222 gas in equilibrium with its progeny [5x10

-4 per working level month (WLM)]. This is approximately twice the value used by the Commission in Publication 65

October 17, 2017

15Slide16

US Public Dose Limits

Presidential Radiation Protection Guidance for the Public (1960)

5

mSv

/y (500 mR/y) whole body

1.7

mSv

/y (170 mR/y) when source is not known50 mSv/30y (5 rem/30s) years to gonadsSpecific organ doses (1961)

NRC 10 CFR 20 1 mSv/y (100 mR

/y) effective dose from the licensed operation

EPA Indoor radon action level (recommendation) remains at 4 pCi/L

October 17, 2017

16Slide17

NCRP Report 116 (1993)

Public Dose Limits

1

mSv

/y (100 mR/y) effective dose continuous exposure5

mSv

/y (500

mR/y) effective dose infrequent exposure1.7 mSv/y (170 mR/y) when source is not knownRemedial Action Limits for NORM

2 WLM (7 x 10-

3

Jh

/

m

3)5 mSv/y (500 mrem/y)

NCRP is updating this report and new recommendations expected soon…

October 17, 2017

17Slide18

DOE Public dose limits

DOE Order 458.1 Ch 2 (2011)

1

mSv

/y (100 mR/y) effective dose15

mSv

/y (1.5 rem) lens of eye – equivalent dose

50 mSv/ ( 5 rem/y) skin and extremities – equivalent dose5 mSv (500 mrem) with approval providing does not exceed 1 mSv

/y averaged over 5 years.Includes TENORM from DOE operationsALARA appliesAdditional dose constraints…

October 17, 2017

18Slide19

TENORM Is Not Regulated Like Other Radioactive Materials

ICRP Principles are not regulations. Each country adopts their own regulations based on ICRP.

ICRP basis for IAEA recommendations and standards.

Most US radiation regulations fall under the Atomic Energy Act of 1946, et seq.

TENORM however, is NOT captured by the Atomic Energy Act

This makes for an uneven playing field with respect to worker safety, public health and environmental protection

TENORM is mostly unintended and those who possess it often do not have the resources to properly manage it

19

October 17, 2017Slide20

TENORM in the U.S.

It is unclear at this time how new dose coefficients and dose limits will impact the TENORM sector

No one agency regulates all public exposures, only those under their authority

The US will likely retain dose limits for all regulated activities

Emphasis will remain on Optimization (ALARA)

Radon remains a difficult challenge

States are primarily responsible for regulating TENORM

Public awareness is increasingICRP is not a regulatory body – these are principles that countries need to adopt into regulation.

20

October 17, 2017Slide21

Summary

ICRP

is evaluating its approach to NORM/TENORM

TG-76 report in process, 2017-2018

Existing situations

may adopt reference bands

Optimization within bands

May result in relaxed radiation protection goals

Planned situation would have dose limits plus optimizationMany issues to address

No final decision anticipated soon

21

October 17, 2017Slide22

Contact information

Philip Egidi

Environmental Scientist

Radiation Protection Division

Office of Radiation and Indoor Air

Washington, DC

202-343-9186

egidi.philip@epa.gov

22

October 17, 2017