Radiation emergencies
Health consequences of radiation
Radiation can either kill or damage living cells. As many of the billions of cells in the human body are
replaced every day, minor exposures to radiation may have little or no appreciable effect on an
individual. Major exposures to radiation, however, can have health effects which can be divided into
deterministic, or acute effects, and stochastic, or late effects. Deterministic effects include skin burns,
radiation sickness and death. Stochastic effects, on the other hand, include cancers and inheritabledefects, which result from damage to the genetic material in cells.
Radiation emergencies can have severe psychological effects on the victims, as the fear of an
unfamiliar, invisible and potentially terrible danger causes acute stress. It must be realized that such
stress and its associated problems can arise even when radiation exposure is low or insignificant.
Radiation from nuclear incidents including accidents in nuclear power plants or research
institutions or from nuclear warfare or terrorism
There are several possibilities that can lead to overexposure of persons to ionizing radiation. Of
these, the more important in peacetime are accidents in nuclear power plants or research institutions
dealing with radioactive materials; and undue exposure to radioactive waste or radioactive source
used in industry, medicine and research laboratories. More recently, a threat of overexposure of
populations to radiation due to terrorism involving nuclear facilities or the theft of radioactive
substances, has become more prominent.
The medical and health response to a radiation emergency depends on its magnitude. The
International Nuclear Event Scale (INES) is a scale that includes eight levels and is used to informthe public about the severity of events at nuclear facilities (see following box).

International Nuclear Event Scale (INES) is used to inform the public about the severity ofevents at nuclear facilities. This scale includes eight levels as indicated below.
Level 0(deviation)
Level 1(anomaly)

An event with no safety significance.

Level 2(incident)

An event involving significant failure in safety provisions, but with
sufficient defence in depth remaining to cope with additional failures,
and/or resulting in a dose to a worker exceeding a statutory dose limit
and/or leading to the presence of activity in on-site areas not expected bydesign and which require corrective action.

Level 3(seriousincident)

A near accident, where only the last layer of defence in depth remained
operational, and/or involving severe spread of contamination on-site or
deterministic effects to a worker, and/or a very small release ofradioactive material off-site (i.e. critical group dose of the order of tenthsof a mSv).

Level 4
(accident
without
significant
off-site risk)

An accident involving significant damage to the installation (e.g. partial
core melt), and/or overexposure of one or more workers resulting in ahigh probability of death, and/or an off-site release such that the criticalgroup dose is of the order of a few mSv.

Level 5
(accidentwith off-siterisk)

An accident resulting in severe damage to the installation and/or an offsite release of activity radiologically equivalent to hundreds or thousands
131of TBq of I, likely to result in partial implementation of countermeasurescovered by emergency plans.
e.g. the 1979 accident at Three Mile Island, USA (severe damage to theinstallation), or the 1957 accident at Windscale, UK (severe damage tothe installation and significant off-site release).

Level 6(serious
accident)

An accident involving a significant release of radioactive material andlikely to require full implementation of planned countermeasures, but lesssevere than a major accident.
e.g. the 1957 accident at Kyshtym, USSR (now in Russian Federation)

Level 7
(majoraccident)

An accident involving a major release of radioactive material withwidespread health and environmental effects.
e.g. the 1986 accident at Chernobyl, USSR (now in Ukraine).

An event beyond the authorized operating regime, but not involving
significant failures in safety provisions, significant spread of contamination
or overexposure of workers.

International and local response to a major nuclear accident in compliance with the“Convention on Early Notification and "Assistance Convention”
In the case of a nuclear accident, the level of radiation hazard for the population depends upon thequantity and principle radionuclides released into the environment, the distance of the populatedareas from the source of radioactive release, the type of buildings and the density of population,
meteorological conditions at the time of the accident, season of the year, character of agriculturaldevelopment in the area, water supplies and nutritional habits and status of the population.
In nuclear reactor accidents involving the release of radioactive material into the atmosphere, thefollowing routes resulting in radiation injury to the population are expected:• external gamma irradiation brought by the passing radioactive cloud;• internal irradiation from inhaling radioactive aerosols (inhalation hazard);• contact radiation due to deposition of radioactive fallout on the skin and clothes;• total external gamma irradiation of the population due to deposition of radioactive
fallout on the soil and local objects (buildings, constructions etc. ); and• internal irradiation resulting from water consumption and local food products
contaminated by radioactive substances.
During a major nuclear accident, the following three phases are identified:• Early Phase – from the threat of a serious release to the first few hours after the
beginning of a release;• Intermediate phase – from the first few hours after the start of the release to one or twodays; and• Recovery Phase – may extend from some weeks to several years.
Information presented in the Annex I (Tables 1-4) gives a general summary of the actions of IAEA,
WHO, other international organizations and local health authorities in response to the nuclear
accident in compliance with the “Convention on Early Notification” and “Assistance Convention” .
Criteria for decision-making on the implementation of countermeasures to protect the population fromradioactive materials released due to a nuclear accident depend on the phase of the accident. At
the early phase and intermediate phase, decisions should be taken on the basis of a comparison
between the estimated radiation doses (calculated at the start of the accident) and intervention levelsof doses given in Tables 1 and 3 of the Annex II. II The dose criteria for taking protective
countermeasures at the early phase refer to often crude dose estimates during a short period of time.
At the recovery phase, decision-making is based on intervention levels of doses presented in Table
2 of the Annex II. The dose criteria for the relocation of the population refer to the estimated dosesof both external and internal radiation during the first year. The dose criteria for the implementationof restrictions on the consumption of radionuclide contaminated food products and drinking waterrefer to estimated doses of internal radiation by radionuclides in food and water consumed within ayear (Table 4, Annex II).

Role of WHO in a radiation emergency
The World Health Organization, as the lead United Nations agency for health issues, has the
responsibility for shaping, coordinating and initiating health-related emergency assistanceprogrammes at the global level. WHO has established a network of collaborating centres, REMPAN.
The role of the collaborating centres in radiation emergencies is outlined in the following Box.
Role of WHO in a radiation emergency
WHO has established a network of collaborating centres - REMPAN - for the promotion of radiation
emergency medical preparedness and for practical assistance and advice to countries in the caseof overexposure from any source of radiation,

Type of accident

Roles of the collaborating centres within REMPAN

A major release ofradioactive
materialfrom a nuclear reactor• provide assistance and advice in the management of
exposed individuals;• provide a team for on-site emergency treatment• transfer (if possible and necessary) of severely exposed
patients to collaborating centres for specialized medical care;• provide a survey team for rapid external radiation monitoring
and/or contamination surveys with appropriate equipment;• provide facilities and staff for medical investigations andtreatment;• assist in the development of measures necessary to limit
health effects; and• provide follow-up medical supervision and treatment

High activity sources
leading
tosevereexposureofsomeindividuals• visit the accident site in order to identify and isolate thesource of irradiation;• make an assessment of likely exposure;• recommend appropriate medical treatment• transfer of patients to specialized medical facilities (ifnecessary and requested); and• assist in the development of procedures to strengthen the
countries abilities to manage such accidents for themselves;• circulate information relating to such incidents for the benefitof member states in general

Excessive exposure ofpatients and/or medical
staff
due
to
the
administrationofradiation for medical
purposesMitigation of effects
In general the first priority is to limit the exposure to radiation which occurs, primarily, throughradioactive fallout, either by evacuation or by sheltering the affected population. Depending on thestrength of the explosion or release and the prevailing meteorological conditions (e.g. wind andprecipitation), a radius of between 30 and several hundreds of kilometers from the explosion
epicentre should be declared a priority area for action. Sheltering may be considered a preliminary
solution before evacuation. Suitable sheltering sites are refuges, caves, mines, and, in general, any
place where there is a barrier of solid substances between radiation and humans. Radiation-free air,water and food will be required to diminish the hazard.
Victims of radiation from nuclear explosions should be moved as quickly as possible to an
appropriate medical establishment. In some types of incidents, hundreds or even thousands ofpeople may need to be examined for external or internal contamination. Such examinations require
specialized equipment. The scope of, and the need for decontamination will depend on whether thereis evidence of body surface contamination. Contaminated clothing will need to be handledappropriately and disposed of according to accepted procedures. The person will require thoroughshowering and the provision of uncontaminated clothing. Any illness should be treated immediately.
131
Where there is evidence of internal contamination with radio-active iodine (I), stable iodine
prophylaxis is needed to avoid excessive thyroid radiation doses and, especially in young people,
to reduce the risk of thyroid cancer in later life (see following box for further information andrecommended dosages).

Stable iodine prophylaxis
Exposure to radioisotopes of iodine following the accidental release of radioiodine can result in asignificant increase in thyroid cancer in, especially, young children. Inhaled and ingested radioiodine
is preferentially taken up by the thyroid and, compared with adolescents and adults, young children’s
thyroids are more radiosensitive.
Stable iodine blocks the uptake of radioactive iodine by the thyroid. It is available in a number offorms and is most effective when taken as close as possible to the first exposure to radioactive
iodine. A single dose will normally protect against inhalation. If a release lasts longer than a day thepreferred response, if practicable, is evacuation. Further doses to protect against the ingestion
pathway may be required if uncontaminated food supplies are not available. The recommended
single doses are:Age
>12 years
3–12 years
1 month to 3 years<1 montha

Recommended dosage
100mg
50mg
25mg
Single does 12.5mg

aequivalent mass of iodine – dose is usually taken as either potassium iodate or potassium iodide

Depending on the results of diagnostic investigations, substantial surgical treatment may be required;this can only be provided by competent, trained physicians and nurses operating in sterile treatment
facilities.
When radionuclide contamination spans national boundaries, international and national authorities
would normally take the lead role in radiation emergencies. However local authorities can play a keyrole in the alleviation of health consequences of radiation emergencies (see following box).

Role of the local authority1
Central government authorities play a large part in all but very minor radiation
emergencies. Affected individuals will often turn first to the local authority for advice,treatment and reassurance. Preparation and planning for radiation emergencies should
not be viewed as the concern of central governments only.
Local authorities that are prepared and have planned for radiation emergencies can assist
in the solution of public health problems in a number of ways.
Before an emergency they can:••Inform and train doctors and other front-line professionals to whom the public arelikely to turn in an emergency.
Inform the public about the possibility of an emergency, its probable consequences
and the probable remedial actions.

During an emergency they can:••••Provide information, guidance and reassurance to the public.
Provide stable iodine prophylaxis where appropriate.
Ensure the availability of immediate medical treatment to those who require it.
Provide advice on the safety of food and beverages.

After an emergency they can:•••Regulate the production and distribution of food.
Organize the provision of long-term health care to the victims.
Support medical, psychological and social recovery.

Addressing public anxiety is a difficult and complex task, and requires very carefulconsideration. The public must be informed of the nature and extent of any emergency
and the likely effects on health. On the other hand, inappropriate and excessive reactions
on the part of the authorities may unjustifiably heighten fears and lead to crowding at
medical facilities as individuals seek information and treatment.
1Source: World Health Organization (1997a).

Care must be taken in the handling of victims externally contaminated by radionuclides, as theradiation that they emit can affect helpers. Their clothes must be changed and they must be bathed.
In handling them, especially in the initial stages, helpers should wear thick clothing and gloves.
Many of the workers in nuclear power plants and research institutions are likely to be technically wellqualified and experienced. They will often be an integral part of the emergency response plan withroles that utilize their broad experience in both the monitoring and cleanup efforts. If it is necessary
to evacuate the population in the vicinity of the accident, radiation levels in air, water and food must
be monitored and health authorities must be prepared to provide safe water and food if these havebeen contaminated.
Prompt, honest, and authoritative warning is very important to enable people to evacuate or to shelter
from the plume (farmers, construction and forest workers, and other outdoor workers may be lessaccessible and more difficult to inform). The monitoring of fallout in down-wind regions and countries
is essential. The exposure of standing crops and the uptake of radionuclides by farm animals is avery important consideration. Unless uncontaminated fodder and water can be provided to cows,
milk may have to be condemned. A program monitoring the radioactivity of food may need to be
inititiated depending on the concentration of radionuclides in the environment (Eheman, 1989, pp.
120–121).
Depending on the levels of radiation and the nature and quantity of the radioisotopes contained in
the fallout, authorities should realize that large-scale evacuation of populations from contaminatedareas may be required for long periods of time (World Health Organization, 1996c). The above
intervention measures, and other measures as required, should be undertaken in accordance with
the intervention levels developed by FAO, IAEA, OECD/NEA, PAHO and WHO (International Atomic
Energy Agency, 1996). Immediately after exposure to radiation (before screening by specialists),
both the alleviation of symptoms and psychological support of victims are very important. It must be
remembered that the most common initial symptom of a radiation overdose - vomiting - can also beof psychosomatic origin and is one that can be rapidly imitated.

Inadvertent exposure to radioactive material
The uses of radioactive materials for industrial, research and therapeutic purposes are manifold andas a result, there is always the possibility of inadvertent exposure of humans. In general, industries
and institutions handling radioactive materials have high safety standards and well-establishedhandling procedures and the workers are generally well protected. The high qualifications of these
personnel and the fact that they are usually well organized, give them the collective strength needed
to fight for a safe work environment.
Apart from medical procedures for which a benefit is clearly defined, the most likely source ofsignificant exposure to radioactive material is discarded or stolen sources whose dangerous
properties are not recognized by the perpetrators.
Such accidents usually come to light when a radioactive source is found to have been mislaid.
Prompt notification to the appropriate authorities and the use of the mass media should make thecommunity aware of the danger. Sometimes the first indication of accidental exposure is theappearance of people with radiation injuries, e.g. radiation burns. When this happens detailed
anamnesis questionnaires should be used, both to clarify the circumstances leading to the exposureand to trace other, as yet unknown, victims. The fact that radiation cannot be perceived by thesenses, and that its first symptoms are very unspecific, compounds the problem. An account of aradiation accident in Brazil is given in the following box:
Poverty and radiation exposure in Brazil
In September 1987, metal scavengers dismantled a canister from a radiotherapy machine in
an abandoned medical clinic in the city of Goiania, in the State of Goias, Brazil The canistercontained almost 1400 curies of caesium-137. Over the following two weeks the luminous blue
caesium chloride was played with by children and widely distributed throughout the community.
A number of the slum dwellers began to immediately exhibit signs of radiation sickness – lossof appetite, nausea, vomiting and diarrhea. By the time authorities were made aware of thesituation more than 250 people had been exposed, 104 individuals showed evidence ofinternal contamination and within four weeks, four of these people had died.
The severity of the accident was exacerbated by the lack of radiation knowledge by the public.
The cause of the accident was the lack of regulation by the responsible authorities. The lackof adequate response time and materials contributed to the casualties and fatalities.

The disposal of radioactive wastes is another potential risk. Waste is produced from various stepsof the nuclear fuel cycle, in the medical use of radioisotopes, by the military and from the widespreadindustrial use of sealed sources. Safety criteria for such disposal exist, and are quite restrictive.
However most countries which produce radioactive wastes still have problems with disposal,
especially for intermediate and high level waste. High level waste may have to be safely stored forthousands of years. This requires deep burial of material in corrosion-resistant containers in ageologically stable region. This and other requirements for a repository mean that many countries
are still addressing the question of disposal. The transport of radioactive material is also a hazardous
procedure, and the potential for injury to human health always exists. However, codes of practicefor the transport of radioactive materials exist in many countries and more than sixty IAEA member
states have adopted the Agencies Regulations for Safe Transport of radioactive Material (Rawl, R.,
Transport Safety, IAEA Bulletin 40, #2, 18-20, 1998)

Further information
For further information on radiation emergencies and health, see World Health Organization (1989d),
International Atomic Energy Agency (1994) Organization for Economic Co-operation andDevelopment (1994), International Atomic Energy Agency (1995), World Health Organization (1995),
International Atomic Energy Agency (1996), and International Federation of Red Cross and Red
Crescent Societies (1998).
1 See also: Web Site <http://www.oes.ca.gov/oeshomep.nsf/all/cep/$file/cep.pdf>

Annex I
INTERNATIONAL AND NATIONAL ACTIONS IN RESPONSE TO A
RADIATION EMERGENCY
Information presented below summarizes in general the actions of WHO, IAEA, other internationalorganizations and local health authorities in response to the nuclear accident in compliance with the“Convention on Early Notification” and “Assistance Convention” in Tables 1-4.

Table 1.

1.

2.

3.

4.

International response at the early phase of the accident

IAEA
Establish direct
telephone links
with the accident
State and thoseStates deemed
to be possibly
affected.
Identify possibly
affected states
within a radius of1000 km fromthe releaselocation.
Contact affectedstates andprovide themwith special
numbers forcontacting the
AgencyStates outside
the 1000 km
zone will also be
rapidly informedof the release,but not on thepriority basis.

WHO/HQ
1.

Develop communication
with Regional Offices andMember States, including
links with the Ministries of
Health of the accident
country, affected states
and those that may beaffected.

2.

Request accident state,
IAEA and WMO to provide
computer modelling mapsof radioactive cloud.

3.

Request ICRP and IRPA
to assist in evaluation of
possible healthconsequences.

4.

Request REMPAN andGERMON members toprovide WHO withinformation on readinessto assist (upon request)
the accident country andaffected states (specify
type of assistance,
including man-power andfinance).

5.

Contact Regional Offices
to mobilize resources(including financial) for theaccident countries andaffected states.

6.

Follow-up of the accident
development and, if
necessary, convene
expert group meeting toobtain recommendations.

Regional offices
1.

If information about
the accident was
obtained from an
accident or affected
country, inform
WHO/HQ.

2.

Establish communications with
WHO/HQ, Ministry of
Health of accident
and affected
countries,
WHO/REMPAN
members in theregion.

3.

Undertake actions
according toemergency plan.

4.

Regularly inform
WHO/HQ about any
progress in thedevelopment of thesituation.

Other internationalorganizations
FAO - Collect andassess information fromIAEA or the accident
country or affected
countries, on possible
food contamination.
Disseminate relevant
information.
WMO - Information on
the direction of any
released radioactive
material should be
issued regularly bydesignated WMO
centres, for transmission
to states andinternationalorganizations.
UNEP - Provide relevant
environmental andnatural resources
information through
GEMS, GRID and
GERMON for the
analysis of data
UNOCHA - Assist incoordination of activities
for mobilizing resources
to overcome
consequences of theaccident.
UN International
Emergency Network-Assist in distribution of
relevant information
after a radiation
emergency.

Table 2.

Priorities of National and Local Response

National andLocal level

Table 3.
accident
IAEA

1.

First medical care to radiation victims

2.

The accident State and affected States provide IAEA and FAO with informationof food and drinking water contamination.

3.

Implementation, if necessary, of the following applicable and possibly essential
countermeasures: sheltering, radioprotective prophylaxis, iodine prophylaxis,
body protection, evacuation, personal decontamination. (See Annexes II and III)4.

If necessary, request assistance of international community.

International and local response at intermediate phase of the

WHO/HQ in cooperation with WHO/ROs
Request 1

No request forassistance
1.

2.

3.

4.

1

Transmitting
request forassistanceand relevant
information

1.

Monitor andstudy thesituation.

2.

Communicate
between
WHO/HQ,
WHO/ROs,
Ministries of
Health of theaffected
countries, andinformationexchanges, etc

Offering its
good offices
to coordinate
assistance tothose states
requestingsupport.
Provideappropriate
resources
allocated forthe purposeof conducting
an initialassessmentof theaccident or
emergency
Developappropriatemonitoring
programmes,

3.

4.

5.

Maintain
REMPAN &GERMON in
operational
readiness

1.

Acknowledge the receipt of
the request. Notify therequesting state directly or
through IAEA if it is in aposition to render therequested assistance andterms of the assistance thatmight be rendered.

1.

Specify the scope and typeof assistance required.

2.

Provide the assisting party
with information as may benecessary to determine theextent to which it is able tomeet the request.

2.

Within the limits of WHO/HQ
and WHO/RO’s capability,
identify and notify the IAEA ofexperts, equipment andmaterials which could bemade available for provisional
assistance.

3.

3.

Inform IAEA and other State
Parties (directly or through
IAEA) of WHO competentauthorities and points ofcontact.

Unless otherwise agreed:
provide the overall direction,
control, coordination andsupervision of theassistance; designate in
consultation with therequesting state a person in
charge who should exercise
his supervision incooperation with theappropriate authority of therequesting state.

4.
4.

Request information incompliance with the checklist.

Provide local facilities andservices for the proper andeffective administration of
the assistance.

5.

Request additional
information, if the informationis seen at WHO/HQ as

5.

Ensure the protection of
personnel, equipment andmaterials brought into its

Mobilize
resources.
Requestadditional
informationfrom theaccident
country,

Local level

May come directly from the accident or affected countries, via IAEA, or other international
intergovernmental organizations

procedures
andstandards
5.

affected
country, IAEA
and otherrelevantorganizations.

Sendradiologicalandemergency
teams to thesite of theaccident.

6.

Convenemeeting ofexperts, if
necessary, toobtain relevant
recommendations.

insufficient.
6.

7.

territory by or on behalf of
the assisting party.

Inform the country about thetype of assistance which will
be sought by WHO from its
REMPAN Collaborating
Centres.
Describe the Collaborating
Centres that will beapproached.

8.

Ask the selected
Collaborating Centre foravailable assistance.

9.

Establish link between therequested country andassisting centre(s), inform
REMPAN of the outcome of
the request.

6.

Ensure the return of theequipment and materials tothe assisting party.

7.

Inform WHO about thetermination of assistance.

8.

Applicablecountermeasures
sheltering; radioprotective
prophylaxis; bodyprotection; decontaminationof areas; evacuation.

9.

Applicable or possibly
essential countermeasures :evacuation; personal
decontamination; relocation;
food control.

10. Keep all REMPAN centres
informed about the details of
the accident and progress in
its management.

Table 4 .

International and local actions at the Recovery Phase of the accidentInternational level

Local level1.

1. Applicable countermeasures- personal decontamination- relocation- control of access

Actions depend on the requests of the accident countries
or affected countries. They may relate to providing
humanitarian assistance to the accident country oraffected countries and facilitating medical andepidemiological follow-up.

2.

Applicable and possibly essential
countermeasures- food control- decontamination of areas

ANNEX II
Selected information from the International Basic Safety standards forProtection against Ionizing Radiation and for the Safety of Radiation
Sources. Jointly sponsored by FAO, IAEA, OECD/NEA, PAHO, WHO, Vienna
1996.
The management of accident situations outlined in the standards are based on the ICRP
principles for planning and deciding interventions to cope with a radiological emergency. These
principles are as follows:♦

All possible efforts should be made to prevent serious deterministic health effects;

♦

The intervention should be justified, in the sense that introduction of the protective measure
should achieve more good than harm;♦

The levels at which the intervention is introduced and at which it is later withdrawn should be
optimized, so that the protective measure(s) will produce a maximum net benefit.
The main criterion for deciding on intervention is the mean individual dose which is expected to
be avoided by the intervention.
Dose levels at which intervention is expected to be undertaken under any circumstances (bejustified) are given in Tables 1 and 2.

Table 1. Intervention level of dose for acute exposure
Organ or tissue

Projected absorbed dose (Gy) to the organ or tissue in lessthan 2 days
Whole body (bone marrow)
1
Lung
6
Skin
3
Thyroid5
Lens of the eye
2
Gonads3
Note:
The possibility of deterministic effects for doses greater than about 0.1 Gy(delivered over less than two days) to the foetus should be taken into account inconsidering justification and optimization of actual intervention levels for immediate
protective action.

Table 2. Intervention level of dose rate for chronic exposure
Organ or tissue
GonadsLens of the eye-1

Equivalent dose rate (Sv.a )
0.2
0.1
0.4

Intervention levels in emergency exposure situations are expressed in terms of avertable dose,
i.e. a protective action is indicated if the dose that can be averted is greater than thecorresponding intervention level. The standards provide the values which can be taken as starting
points for the judgement required for decisions to select levels for emergency exposure situations.
These values have been developed by IAEA and summarized in Table 3.

Table 3. Recommended generic intervention levels for urgent protective measures
Protective action
Sheltering
Temporary evacuation
Iodine prophylaxis

Generic intervention level (dose avertable by the protective
action)
10 mSv in a period of no more than two days
50 mSv in a period of no more than one week
100 mSv (absorbed dose due to radioiodine) *)*) For children WHO recommends 10mSv.

The recommended generic action levels for foodstuffs are presented inTable 4.
Table 4. Generic action levels for foodstuffs (Bq/kg)
Radionuclides

Cs-134, Cs-137, Ru-103,
Ru-106, Sr-89
I-131
Sr-90
Am-241, Pu-238, Pu-239

Food for general consumption(kBq/kg)

Milk and infant foods drinking
water (kBq/kg)

1000
1000
1000
100
10

1000
1000
100
100
1

It is noted that levels given in Table 5 apply to situations where alternative food supplies are readily
available. Where food supplies are scarce, higher levels can apply.
Table 4 is based on, and consistent with, the Codex Alimentarius Commission’s guideline levels
for radionuclides in food moving in international trade following accidental contamination, but it islimited to the nuclides usually considered relevant to emergency exposure situations.

The generic optimized intervention levels recommended for temporary relocation and permanent
resettlement are given in Table 5.
Table 5. Recommended generic intervention levels for temporary relocationand permanent resettlement
Actions
Avertable dose
Initiating temporary relocation
30 mSv in a month
Terminating temporary relocation
10 mSv in a month
Permanent relocation
1 Sv in lifetime