The following is an excerpt from
ICRP PUBLICATION 146

Radiological Protection of People and theEnvironment in the Event of a Large
Nuclear Accident
Annals of the ICRP 49(4) 2020

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ANNALS OF THE

PUBLICATION 146
Radiological Protection of People andthe Environment in the Event of a
Large Nuclear Accident
VOLUME 49 NO. 4, 2020

ISSN 0146-6453 • ISBN 9781529767582

Annals of the ICRPICRP PUBLICATION 146

Radiological Protection of People andthe Environment in the Event of a
Large Nuclear Accident
Update of ICRP Publications 109 and 111
Editor-in-Chief
C.H. CLEMENT
Associate Editor
H. FUJITA
Authors on behalf of ICRP
M. Kai, T. Homma, J. Lochard, T. Schneider, J.F. Lecomte,
A. Nisbet, S. Shinkarev, V. Averin, T. Lazo
PUBLISHED FOR
The International Commission on Radiological Protection
byPlease cite this issue as ‘ICRP, 2020. Radiological protection ofpeople and the environment in the event of a large nuclear accident:
update of ICRP Publications 109 and 111. ICRP Publication 146.
Ann. ICRP 49(4).’1

CONTENTS
EDITORIAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

05

ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11

MAIN POINTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13

EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

191.1. Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2. Scope and structure of the publication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

19
20

2. GENERAL CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

21

2.1. Timeline for managing a nuclear accident . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2. Consequences of a large nuclear accident . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3. Principles for protection of people and the environment . . . . . . . . . . . . . .

21
22
28

3. THE EARLY AND INTERMEDIATE PHASES . . . . . . . . . . . . . . . . . . . . . . . . .

39

3.1. Characteristics of the early and intermediate phases . . . . . . . . . . . . . . . . . .
3.2. Radiological characterisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3. Protection of responders during the early and intermediate phases . . . .
3.4. Protection of the public and the environment in the early
and intermediate phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5. Moving from the intermediate phase to the long-term phase . . . . . . . . . .

39
40
43

4. THE LONG-TERM PHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

63

4.1. Characteristics of the long-term phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2. Radiological characterisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3. Protection of responders during the long-term phase. . . . . . . . . . . . . . . . . .
4.4. Protection of the public and the environment in the long-term phase. .
4.5. Evolution and termination of long-term protective actions . . . . . . . . . . . .

63
64
65
66
73

5. PREPAREDNESS PLANNING FOR A LARGE NUCLEAR
ACCIDENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

75

6. CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

77

3

48
60

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7. INTRODUCTION TO THE ANNEXES: AN OVERVIEW OF THE
CHERNOBYL AND FUKUSHIMA NUCLEAR ACCIDENTS. . . . . . . . . .

81

REFERENCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

83

ANNEX A. THE CHERNOBYL NUCLEAR ACCIDENT . . . . . . . . . . . . . . . . .

89

A.1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
A.2. Early and intermediate phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
A.3. Long-term phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
A.4. Timeline of the phases of the Chernobyl accident . . . . . . . . . . . . . . . . . . . 105
A.5. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
ANNEX B. THE FUKUSHIMA NUCLEAR ACCIDENT. . . . . . . . . . . . . . . . . 109
B.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B.2. Early and intermediate phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B.3. Long-term phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B.4. Timeline of the phases of the Fukushima accident . . . . . . . . . . . . . . . . . . .
B.5. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

109
110
119
125
125

GLOSSARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
ACKNOWLEDGEMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

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ICRP Publication 146

Editorial
BE PREPARED
Accidents happen. Aircraft crash, ships sink, trains derail, chemical factories
explode, dams break, and nuclear power plants fail. We also face natural disasters
such as ﬂoods, droughts, hurricanes and typhoons, earthquakes, heat waves, volcanic eruptions, tornados, meteor strikes, forest ﬁres, ice storms, mud slides, andtsunami. Each of these can shake a city, region, or nation. A few have shaken theworld. The consequences can be political, societal, environmental, economic, and,most of all, human.
At the heart of accidents and disasters are personal consequences. The most obviousof these are physical injury and death, sometimes on a massive scale. On 3 December
1984, a leak from a pesticide factory in Bhopal, India killed at least 3000 people andmore than 100,000 suﬀered permanent disability. Compensation for injury wasawarded to more than half a million people (Broughton, 2005).
These ﬁgures are staggering, but looking more deeply reveals that the consequencesof accidents and disasters go far beyond the obvious. A ﬂood can destroy a village,
washing away homes that have stood for generations and destroying culturally signiﬁcant places, breaking a community’s connection with its own history. Releases
from facilities can taint entire regions whether there are immediate health consequences or not. Even if people can continue to live there, property values drop,
populations dwindle, and job opportunities disappear as new people and businesses
are reluctant to move in. Looking even more closely, consider the despair of grandparents whose grandchildren will no longer visit them in their homes, or families thatbreak apart because of conﬂicting priorities.
Learning to deal with accidents and natural disasters is essential to reduce humansuﬀering and environmental impacts.
Everyone hopes that there will never be another nuclear accident on the scale of what
occurred in 2011 at the Fukushima Daiichi nuclear power plant in Japan, or, evenworse, in 1986 at the Chernobyl nuclear power plant in the USSR (now Ukraine).
Today, there are approximately 440 nuclear power reactors supplying electricity
globally, and approximately 15 more are under construction (WNA, 2020).

5ICRP Publication 146

ICRP has no position on nuclear power beyond the ethical principles and fundamental recommendations that apply universally. Ethically, this means that goodmust be preferred over harm, actions must be well informed and carefully considered, and people must be treated fairly and with dignity. We call these the four
core ethical values of beneﬁcence/non-maleﬁcence, prudence, justice, and dignity(ICRP, 2018). To enact these, we use the three principles of radiological protection:
justiﬁcation, optimisation of protection, and individual dose limitation. Respectively,
these ensure that good outweighs harm, that protection is the best for the circumstances, and that an unfair dose is not imposed on any individual. In short, ICRP’s
aim in all circumstances is to ensure that, where ionising radiation is involved, people
and the environment are protected.
Given this, ICRP applauds all eﬀorts to improve nuclear safety (e.g. NEA, 2016).
Our mission is to promote radiological protection. Avoiding and mitigating nuclear
accidents, especially those that release radioactive material, are part of protecting
people and the environment from detrimental exposures to radiation.
Nonetheless, we must be prepared for another accident. This is an important part ofour work, related not only to nuclear power but also, for example, the use of radiation in medicine [see, for example, Publication 112 ‘Preventing Accidental
Exposures from New External Beam Radiation Therapy Technologies’ (ICRP,
2009a)].
The present publication updates and replaces two previous publications, coincidentally released in the same year as Publication 112, and less than 2 years before the
Fukushima Daiichi accident:. Publication 109 ‘Application of the Commission’s Recommendations for theProtection of People in Emergency Exposure Situations’ (ICRP, 2009b); and. Publication 111 ‘Application of the Commission’s Recommendations to theProtection of People Living in Long-term Contaminated Areas’ (ICRP, 2009c).
In theory, the scope of the present publication is narrower than that of Publications
109 and 111, as it applies speciﬁcally to large nuclear accidents. In practice, theseprevious publications focused largely on these types of accidents, although the general principles are the same for accidents of almost any scale. Even so, additional
recommendations on radiological protection for other types of accidents are being
considered.
One of the advantages of combining the two previous publications into one is thatthe response can be considered more holistically, and more attention can be paid to
the transition from the early and intermediate phases to the long-term phase of theaccident. The current publication makes it easier to follow the thread through the6Radiological protection of people and the environment in the event of a large nuclear accident

emergency response to the recovery process, and importantly includes advice on
preparation for the long-term phase.
As one might expect, the present publication draws heavily on nearly 10 years ofexperience following the Fukushima Daiichi accident. However, even after nearly 35
years, there are new insights from the Chernobyl accident too. For example, it is now
clearer to see the social impacts of the Chernobyl accident in light of the Fukushima
Daiichi accident, and the Fukushima Daiichi accident has taught us that there can beenormous impacts even without immediate and widespread catastrophic healthimpacts. Reporting on the Fukushima Daiichi accident, the United Nations
Scientiﬁc Committee on the Eﬀects of Atomic Radiation noted that ‘no radiationrelated deaths or acute diseases have been observed among the workers and generalpublic exposed to radiation from the accident’ and ‘no discernible increased incidence of radiation-related health eﬀects are expected among exposed members of the
public or their descendants’; however ‘the most important health eﬀect is on mental
and social well-being’ (UNSCEAR, 2013).
This publication could not have been developed in a vacuum. Over nearly a decade,
ICRP embarked on what was perhaps its most extensive work stream since thedevelopment of our last fundamental recommendations (ICRP, 2007). The ICRP
Main Commission met with delegates from Japan in April 2011, just weeks after the
Fukushima Daiichi accident. Soon thereafter, ICRP established Task Group 84 on
Initial Lessons Learned from the NPP Accident in Japan vis-à-vis the ICRP System
of Radiological Protection. The next year, a summary of the task group ﬁndings(ICRP, 2012) was accepted by the Main Commission at their meeting in Fukushima
City, and not long after, members of Task Group 84 published a paper with considerably more detail (González et al., 2013).
This initial assessment would inﬂuence ICRP’s programme of work for many years.
Notably, this included establishing Task Group 93 on Update of ICRP Publications
109 and 111: the group that developed the present publication.
In parallel, ICRP had begun a series of dialogue meetings in Fukushima, the ﬁrst ofwhich was held in November 2011. The purposes were: to create a forum for free andopen discussion of challenges in the recovery process; to share experiences amongexperts and citizens of Japan and countries directly impacted by the Chernobyl
accident, such as Belarus and Norway; to learn about the situation directly fromthose involved to ensure that any new ICRP recommendations would be as relevant
and useful as possible; and, of course, to help people who were facing a very diﬃcult
situation (Kotoba, 2015). What became known as the ‘Dialogue Initiative’ proved tobe highly successful on all counts. As of 2020, a total of 22 dialogue meetings havebeen held, initially led by ICRP but now fully in the hands of local people (Lochard
et al., 2019).

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ICRP Publication 146

The Dialogue Initiative was invaluable in developing the current publication. Not
only did the close interactions with people on the front lines provide a deeper level ofunderstanding, but several local participants also participated in drafting and reviewof the present publication.
Throughout the process, ICRP was also in frequent contact with many experts,
health professionals, aﬀected residents, and authorities including Japanese government and expert organisations and nuclear power plant operators, to ensure that all
aspects of radiological protection after a large nuclear accident were addressed.
A number of international organisations were involved in the development of the
publication. This was through many relatively informal interactions during drafting,and through a more formal peer review later in the process.
All ICRP publications now undergo public consultation before they are completed.
This crucial step gives anyone the opportunity to comment on our work via a webbased portal, and is important to make sure we have heard and considered all viewpoints. Given the nature of this publication, and the signiﬁcant interest expressed bymany people, for the ﬁrst time ever, comments were accepted in English andJapanese, and the comment period was extended. Another ﬁrst was a public meeting
held in Japan during the consultation, so people could hear how we were responding
to early comments, and have an opportunity to express their views in person. In all,more than 300 sets of comments were received, approximately 10 times more than for
most ICRP publications, and second only to the number of comments received on
the current set of fundamental recommendations (ICRP, 2007). I am convinced that
this level of interest has increased the quality of this publication, and am thankfulthat so many people took the time to share their views.
Finally, on a more personal note, I would like to acknowledge the kindness of themany people from and in Japan who I have had the pleasure of meeting since 2011,
and the European friends and colleagues who have shared their experiences related
to the Chernobyl accident. On many occasions, I have been humbled by their perseverance, ingenuity, and generosity of spirit. I am saddened that the accidents happened, and know that people are still suﬀering, but one silver lining is the friendshipsthat have grown between people that would not otherwise have met. I hope anothersilver lining is a more robust understanding of the consequences of nuclear accidents
and improved preparedness for the future.
CHRISTOPHER H. CLEMENTEDITOR-IN-CHIEF

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Radiological protection of people and the environment in the event of a large nuclear accident

REFERENCES
Broughton, E., 2005. The Bhopal disaster and its aftermath: a review. Environ. Health 4, 6.
González, A.J., Akashi, M., Boice, Jr, J.D., et al., 2013. Radiological protection issues arisingduring and after the Fukushima nuclear reactor accident. J. Radiol. Prot. 33, 497–571.
ICRP, 2007. The 2007 Recommendations of the International Commission on RadiologicalProtection. ICRP Publication 103. Ann. ICRP 37(2–4).
ICRP, 2009a. Preventing accidental exposures from new external beam radiation therapy
technologies. ICRP Publication 112. Ann. ICRP 39(4).
ICRP, 2009b. Application of the Commission’s recommendations for the protection of people
in emergency exposure situations. ICRP Publication 109. Ann. ICRP 39(1).
ICRP, 2009c. Application of the Commission’s recommendations to the protection of people
living in long-term contaminated areas. ICRP Publication 111. Ann. ICRP 39(3).
ICRP, 2012. Report of ICRP Task Group 84 on Initial Lessons Learned from the Nuclear
Power Plant Accident in Japan vis-à-vis the ICRP System of Radiological Protection. Ref
4832-8604-9553.
ICRP,
Ottawa.
Availableat:
http://www.icrp.org/docs/
ICRP%20TG84%20Summary%20Report.pdf (last accessed 23 September 2020).
ICRP, 2018. Ethical foundations of the system of radiological protection. ICRP Publication
138. Ann. ICRP 47(1).
Kotoba, 2015. A Web Documentary on the Fukushima Dialogue Initiative. Institut de radioprotection et de sûreté nucléaire, Fontenay aux Roses. Available at: http://www.fukushima-dialogues.com (last accessed 26 October 2020).
Lochard, J., Schneider, T., Ando, R., et al., 2019. An overview of the dialogue meetings
initiated by ICRP in Japan after the Fukushima accident. Radioprotection 54, 87–101.
NEA, 2016. Five Years after the Fukushima Daiichi Accident: Nuclear Safety Improvements
and Lessons Learnt. NEA No. 7284. Nuclear Energy Agency of the Organisation for
Economic Cooperation and Development, Paris.
UNSCEAR, 2013. Report of the United Nations Scientific Committee on the Effects ofAtomic Radiation to the General Assembly. United Nations, New York.
WNA, 2000. Nuclear Power in the World Today. World Nuclear Association, London.
Available at: https://www.world-nuclear.org/information-library/current-and-future-generation/nuclear-power-in-the-world-today.aspx (last accessed 7 July 2020).

9ICRP Publication 146

RADIOLOGICAL PROTECTION OF PEOPLE AND
THE ENVIRONMENT IN THE EVENT OF A LARGENUCLEAR ACCIDENT: UPDATE OF ICRP PUBLICATIONS
109 AND 111
ICRP PUBLICATION 146
Approved by the Commission in July 2020

Abstract–This publication provides a framework for the protection of people and theenvironment in a large nuclear accident, drawing on experience of the Chernobyl and
Fukushima accidents. In managing accidents, the Commission makes a distinction
between the early and intermediate phases, considered emergency exposure situations, and the long-term phase, considered an existing exposure situation. In emergency and existing exposure situations, mitigating the radiological consequences onhumans and the environment is achieved using the fundamental principles of justification of decisions and optimisation of protection. The Commission recommends a
set of reference levels for the optimisation of protection of the general population
and responders, both on-site and off-site, for all accident phases. Implementation ofprotective actions should not only take account of radiological factors, but also
consider societal, environmental, and economic aspects to protect health, ensuresustainable living conditions for the affected people, ensure suitable working conditions for the responders, and maintain the quality of the environment. In the earlyphase of an accident, urgent protective actions have to be taken, often with little
information. Decisions rely on actions identified during preparedness planning thatbest match the actual situation. During the intermediate phase, protective actions
reduce radiation exposures progressively. When the radiological situation is sufficiently characterised, the long-term phase begins, during which further protective
actions are implemented to improve living and working conditions. Authorities
should invite key representative stakeholders to participate in the preparedness process, and in the management of the successive phases of the accident. It is the role of
the authorities to implement radiation monitoring and health surveillance, and to11

ICRP Publication 146

provide the conditions and means for sharing information and expertise to enable
individuals to develop a radiological protection culture and to make informed decisions about their own protection.
ß 2020 ICRP. Published by SAGE.
Keywords: Chernobyl accident; Fukushima accident; Emergency exposure situation;
Existing exposure situation; Justification; Optimisation; Reference level; Protective
actions; Stakeholder involvement; Co-expertise process; Radiological protection
culture12

MAIN POINTS. A large nuclear accident causes a breakdown in society aﬀecting all aspects ofindividual and community life. It has large and long-lasting societal, environmental,
and economic consequences.
. Characterisation of the radiological situation on-site and oﬀ-site is essential to guide
protective actions, and should be conducted as quickly as possible.
. The Commission recommends using reference levels to guide the implementation ofprotective actions during the early, intermediate, and long-term phases of an
accident.
. The objective of radiological protection is to mitigate radiological consequences forpeople and the environment whilst, at the same time, ensuring sustainable living
conditions for the aﬀected people, suitable working conditions for the responders,and maintaining the quality of the environment.
. Responders, who are likely to be the most exposed individuals, should be provided
with appropriate protection, taking into account the requirements of the response onsite and oﬀ-site.
. Responsible organisations should promote the involvement of local communities in a
co-operative process with experts (co-expertise process) to help achieve a better
assessment of the local situation, the development of an adequate practical radiological protection culture, and informed decision-making among those aﬀected.
. Preparedness planning is essential for mitigating the consequences during phases of alarge nuclear accident, and should involve stakeholders.

13

EXECUTIVE SUMMARY(a) Large nuclear accidents result when there are signiﬁcant releases of radioactive
material into the environment, impacting widespread areas and aﬀecting extensive
populations. They are unexpected events that profoundly aﬀect individuals, society,and the environment. They generate complex situations and legitimate concerns,
particularly regarding health, for all those aﬀected by the presence of undesirable
sources of radioactivity. Management of these situations requires the long-term
mobilisation of considerable human and ﬁnancial resources. Radiological protection,although indispensable, only represents one dimension of the contributions that need
to be mobilised to cope with the issues facing all aﬀected individuals andorganisations.
(b) For managing these events, the Commission makes a distinction between theearly and intermediate phases of the accident, considered as emergency exposure
situations, and the long-term phase, considered as an existing exposure situation.
The Commission also distinguishes between on-site and oﬀ-site to diﬀerentiate activities at the damaged installation and in the aﬀected areas. The present recommendations may be applicable to other types of radiological emergencies, with due
consideration of the diﬀerences that inevitably exist between a nuclear accident
and these emergencies.
(c) Characterisation of the radiological situation on-site and oﬀ-site is essential toguide protective actions, and should be conducted as quickly as possible to address
the uncertainties regarding the intensity, duration, and extent of the radioactive
contamination.
(d) In emergency and existing exposure situations, the objectives of radiologicalprotection are achieved using the fundamental principles of justiﬁcation and optimisation. The principle of justiﬁcation ensures that decisions regarding the implementation of protective actions result in a beneﬁt for the aﬀected people and theenvironment, as these actions can potentially induce signiﬁcant disruption. The principle of optimisation of protection applied with reference levels aims to limit inequity
in the distribution of individual exposures, and to maintain or reduce all exposures to
as low as reasonably achievable, taking into account societal, environmental, andeconomic factors.
(e) Justiﬁcation and optimisation are applied in the mitigation of radiologicalconsequences to people and the environment during all phases of the accident, andshould take careful account of all non-radiological factors in order to preserve or
restore the living and working conditions of all those aﬀected, including decent lifestyles and livelihoods.
(f) People involved in the direct management of the consequences of a nuclear
accident are diverse in terms of their background, status, degree of preparation, andtraining on radiological protection. They include emergency teams (ﬁreﬁghters,
police oﬃcers, medical personnel, etc.), workers (occupationally exposed or not),and other people such as elected representatives or citizens acting as
volunteers. All these categories are considered by the Commission as ‘responders’.
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ICRP Publication 146

They deserve to be adequately protected and provided with suitable working
conditions.
(g) For the protection of responders on-site, the reference level during the earlyphase should not generally exceed 100 mSv, while recognising that higher levels, inthe range of a few hundred millisieverts, may be permitted to responders in exceptional circumstances to save lives or to prevent further degradation at the facility
leading to catastrophic conditions. Lower reference levels may be selected based on
the situation, in accordance with the severity of the accident. During the intermediatephase, the reference level should not exceed 100 mSv. For the long-term phase, thereference level should not exceed 20 mSv per year, with possible special arrangements
limited in time. The Commission recommends that responsible organisations shouldtake all practical actions to avoid unnecessary accumulation of exposures for responders involved in both the early and intermediate phases.
(h) For the protection of responders oﬀ-site, the Commission recommends selection of a reference level not exceeding 100 mSv for the early phase and 20mSv per
year for the intermediate phase. For the long-term phase, the reference level should
be selected within the lower half of the recommended band of 1–20 mSv per year.
(i) For the protection of people, the reference level should not generally exceed
100 mSv for the entire duration of both the early and intermediate phases. The
Commission recommends that responsible organisations should adopt a lower reference level whenever possible. For the long-term phase, the reference level should
be selected in the lower half of the recommended band of 1–20 mSv per year forexisting exposure situations, taking into account the actual distribution of doses in
the population and the societal, environmental, and economic factors inﬂuencing
the exposure situation. The objective of optimisation of protection is a progressive
reduction in exposure to levels towards the lower end of the band, or below if
possible.
(j) In some nuclear accident scenarios, release of radioactive iodine can result inhigh thyroid exposures due to inhalation or ingestion. Speciﬁc eﬀorts should be madeto avoid, or at least reduce, intakes of radioactive iodine, particularly in children andpregnant women. During the early phase or just after, exposed people should bemonitored to detect potential exposure to radioactive iodine.
(k) Management of the protection of people in aﬀected areas in the intermediateand long-term phases is a complex process involving not only radiological factors,
but also societal, environmental, and economic considerations. This process includes
actions implemented by national and local authorities, and self-help protective
actions taken by residents of the aﬀected areas. In these phases, radiation exposuresof people living and working in aﬀected areas are largely dependent upon individual
lifestyles. The Commission recommends that authorities, experts, and stakeholders
should co-operate in the so-called ‘co-expertise process’ to share experience andinformation, promote involvement in local communities, and develop a practicalradiological protection culture to enable people to make informed decisions.
Individual measurements with suitable devices, together with relevant information,
are very helpful in the implementation of this process.
16

Radiological protection of people and the environment in the event of a large nuclear accident(l) For the protection of the environment, the Commission recommends that faunaand ﬂora should be protected using its framework based on Reference Animals andPlants, together with derived consideration reference levels. The impacts of protective actions on pets and livestock, as well as on the environment, in terms of sustainable development, conservation, preservation, and maintenance of biologicaldiversity should also be addressed.
(m) The Commission recommends that plans should be prepared in advance to
avoid severe and long-term consequences following a nuclear accident. Such preparedness plans should comprise a set of consistent protective actions, adapted to
local conditions at nuclear sites, taking into account the societal, environmental, andeconomic factors that will aﬀect the impact of the accident and its response.

17