Emergency Response and Civil Protection
The safety of nuclear installations, radioactive waste management facilities and radiation sources is ensured by design features, multi-level protection system and operational procedures.
Establishment of legislative and regulatory safety requirements and mechanisms for their control, training system, knowledge verification and maintaining competencies, introduction of authorization principle of nuclear energy use for peaceful purposes and safety culture philosophy at all levels are aimed primarily at preventing nuclear emergencies in the field of nuclear energy use. At the same time, despite the very low probability of emergencies, preparedness for response remains one of the fundamental principles of safe nuclear energy use.
Protecting the population from emergencies is the state function. A licensee, an employer, the regulatory body, public authorities have to develop measures in advance to ensure preparedness and response in the event of a nuclear or radiation emergency at the place of the event, and, if necessary, at the local, regional, national and international levels to reduce radiation risks in anticipated cases to insignificant level, and to minimize negative consequences for difficult-to-predict events negative by timely response.
Not all types of emergencies are accompanied by releases of radioactive substances that can cause harm to human health and the environment. Nuclear installation designs identify initiating events, end states and anticipated safety systems to limit radiation consequences for anticipated emergencies. The most dangerous consequences for humans and the environment can have events not envisaged by the design, which are accompanied by core control loss, self-sustained chain fission reaction or radiation source. Just to avoid the conditions for initiation of such unlikely events and their harmful consequences, measures to prevent failures, emergencies and safety systems malfunctions that could lead to loss of control are planned and implemented.
The three major accidents at nuclear power plants (Three Mile Island, USA: 1979; Chornobyl, USSR: 1986; Fukushima, Japan: 2011) were the result of a coincidence and a combination of several internal and external hazard factors. They have not only led to large-scale problems in the areas of health, environment, long-term needs for psychological, social and economic recovery, but have also boosted a revision of safety requirements, designing more reliable safety systems, elaboration of procedures for efficient response, including public awareness and maintaining public trust.
One of the tools to inform the public and mass media on assessment results of the impact of events on safety is the International Nuclear and Radiological Event Scale (INES).
Level 4 to 7 events of on the INES scale are accidents that have an impact and require response measures outside sites of the installation. Level 1 to 3 events are classified as incidents or anomalies that affect safety. Classification of an event at the level 0 means that the impact of such an event on safety is insignificant.
More details are available in the INES User’s Manual on the IAEA web site.
For the last 20 years no operational events higher than level 1 (anomaly) according to the INES scale have been identified at the operating Ukrainian NPPs.
The defense-in-depth concept, which is the basis of the up-to-date reactor designs, is an integrity of consistent physical barriers on the way of radioactive substances and ionizing radiation spread and aims to prevent deviations from normal operating conditions, prevent accidents and limit their consequences.
If at least one of the four protection barriers remains intact, the goal to prevent the release of radioactivity into the environment is achieved. If, despite all preventive and emergency measures, the release cannot be avoided, emergency plans shall be put in place. Their purpose is to mitigate emergency consequences and to organize protection of the public and territories beyond the sites of nuclear installations.
To plan the response measures, the following classes of radiation accidents can be identified:
- industrial accident is a radiation accident, consequences of which do not extend beyond the facility and the territory of production premises, and only personnel can be affected by the emergency exposure;
- site accident is a radiation accident, consequences of which are limited to the territory of the industrial site of the facility, but require emergency preparedness of manpower and means of external organizations and carrying out intensified radiation monitoring;
- municipal accident (general) is a radiation accident, consequences of which go beyond the industrial site and can spread to the territory of the public residence and create risks in addition to natural external and internal exposure.
Nuclear facilities meet the basic nuclear safety criteria if the probability of emergencies that may require urgent measures to protect the public outside the nuclear facility control area is approximately 1 case out of 100,000 (or 1×10-6) per year.
Restrictions on the use of land within the nuclear facility control area (within 2.5 — 3 km) and a prohibition on permanent residence and placement of social facilities, as well as other enterprises not related to nuclear facilities are implemented as a preventive measure.
Civil protection system in Ukraine
According to the Civil Protection Code of Ukraine, the Unified State Civil Protection System (USCPS) is a set of governing bodies, man power and means of central and local executive bodies, the Council of Ministers of the Autonomous Republic of Crimea, executive bodies of councils, enterprises, institutions and organizations ensuring implementation of the state policy in the field of civil protection.
Coordinating bodies are state, regional, and local commissions on the issues of man-induced and ecological safety and emergencies, emergency commissions of enterprises, institutions, organizations, and state, regional, local and facility special commissions established to coordinate the activities of central and local executive power authorities.
The USCPS components are functional subsystems established by central executive bodies in the corresponding areas of activity (i. e. the nuclear and radiation safety functional subsystem, safety of electric power and nuclear-industrial complexes functional subsystem, teaching preschool children, pupils and students to act in emergency situations functional subsystem etc), and territorial subsystems that are formed and operate within the administrative territorial units.
The nuclear and radiation safety functional subsystem was established by the SNRIU to protect personnel, public and territories from harmful effects of ionizing radiation by preventing nuclear and radiation accidents at nuclear power facilities and during transportation of radioactive materials, ensuring prompt response in case of emergencies, notification and keeping informed interested state authorities, the public (through the mass media), the IAEA Incident and Emergency Centre, competent authorities of other countries in the framework of international agreements in the case of transboundary transfer of radioactive substances.
The nuclear and radiation safety functional subsystem includes the State Nuclear Regulatory Inspectorate of Ukraine, management bodies and civil protection forces of economic entities subordinate to it and economic entities in the field of nuclear energy use. According to the law, it is the licensee (operating organization) who, after obtaining the relevant authorization of the SNRIU, bears full responsibility for radiation and physical protection and safety of a nuclear installation, radioactive waste management facility or other radiation sources.
The Provisions on the nuclear and radiation safety functional subsystem is available by the link.
Despite the very low probability of municipal/general accidents with the release of radioactive substances, the facility emergency plans of NPPs and other nuclear installations provide for the following emergency response measures within the Unified State Civil Protection System, namely:
- immediate notification of dispatching services and the state response body on an NPP operational event,
- prompt assessment and prediction of the situation development as a basis for issuing recommendations to local authorities to make decisions on introduction of urgent measures for radiation protection of public (shelter, iodine prophylaxis, evacuation, restriction of consumption of local food and water from open water reservoirs);
- intensified radiation monitoring in the control area and the observation area of nuclear installations.
The Emergency Preparedness and Response System of NNEGC “Energoatom” (NNEGC “Energoatom” EPRS) is a component of the functional subsystem “Safety of Electric Power and Nuclear Industrial Complexes” of the USCPS, which is being established by the Ministry of Energy of Ukraine.
In the event an NPP notifies on a municipal/general accident, the following shall be immediately activated:
- NPP emergency plan;
- emergency plan of the of NNEGC “Energoatom” Directorate;
- response plans of local and regional territorial subsystems of the unified state civil protection system, the territory of which belongs to the NPP observation area;
- response plans of other functional USCPS subsystems;
- and a state-level emergency response plan, which envisages establishing an interagency Headquarters that analyzes the situation and identifies actions for further emergency response at the state-level and elimination of an emergency consequences.
Efficiency and consistency of emergency plans is checked during emergency exercises and during the scheduled annual comprehensive inspections of the preparedness state to respond and ensure emergency measures in the event of threat or occurrence of radiation and nuclear accidents, other emergencies of man-induced and natural nature.
Specially trained emergency groups and teams are directly involved in elimination of the radiation accident consequences. Emergency kits of control and measuring devices and equipment, personal protective equipment, decontamination and sanitation means, tools and accessories, special equipment, vehicles and other emergency technical means for immediate use by emergency groups and crews in case of an emergency have been created and are maintained in a ready-to-use state at all NPPs.
A separated subdivision “Emergency and Technical Centre” (ETC) functions within the NNEGC “Energoatom” structure. The main tasks of ETC are to ensure permanent preparedness for rapid and efficient actions in case of radiation accidents at nuclear power plants and during radiation-hazardous cargo transportation taking into account Ukraine’s international obligations and IAEA safety requirements. The other ETC tasks are performance of special engineering activities including using robotics at nuclear energy facilities.
Functions and tasks of the state regulatory body, other central executive power bodies involved in elimination of the state-level emergency consequences are defined by the “State-Level Emergency Response Plan” approved by the Cabinet of Ministers of Ukraine dated No. 223 on 14 March 2018 (as amended according to the resolution of the Cabinet of Ministers No. 916 dated 06 November 2019).
Thus, in the event of an emergency, the NPP notifies and further informs functional and territorial USCPS subsystems, classifies emergencies, assesses the radiation situation, and predicts development and dynamics of radiation state changes. At the first stages of emergency response, it is the operator of the nuclear installation who acts as the main and only source of primary information. Decisions on introduction of radiation protection measures of the public based on information received from the operator on status of the nuclear facility and predicted estimation are made by local executive authorities.
The main objectives of the emergency response are to restore control over the situation and mitigate its consequences, save lives, prevent or minimize radiobiological consequences.
Notification and informing the public
One of the major factors affecting health is unjustified concern when people believe that they or their relatives have been adversely affected by radiation. Therefore, priority should be given to dissemination of timely, reliable and useful information for the public through trustworthy information sources. People residing rather far are sometimes more anxious and stressed by uncertainty than those living close to the event location.
Special warning systems are in place at nuclear power plants. The systems cover the territory of the industrial site, NPP control and surveillance areas within a radius of 30 km (Part 2, Article 53 of the Civil Protection Code of Ukraine; paras 12 and 13 of the Cabinet Resolution No. 733 dated 27 December 2017 “On Approval of the Provisions on Organization of Notification of the Threat of Occurrence or Occurrence of Emergencies and Communication in the Field of Civil Protection”).
Notification of the public in the NPP observation areas and areas of possible spread of radioactive contamination due to an NPP emergency is carried out by operational duty services of local executive bodies and local governments, which, in turn, receive initial notification from the NPP shift supervisor and/or NPP Director General.
Local executive bodies and local self-government bodies also perform functions of the territorial USCPS subsystem management authorities. It is their responsibility to provide the public with timely information on potential hazard of nuclear or radiation emergency in certain areas, nature of the hazards, warning and notification procedures and the measures to be taken in the event of such emergencies.
In case of an emergency, the territorial USCPS subsystems management bodies inform the public on the radiation situation, its changes and decide on the need for shelter, iodine prophylaxis, evacuation, restriction of consumption of agricultural products in the emergency impact area, organize their implementation in the established order.
The decision to implement urgent and long-term countermeasures to protect public health shall be taken as soon as possible in two main response phases:
- “acute” phase, when it comes to implementation of emergency measures immediately after the notification and initial classification of an emergency, and the conditions at the site are not yet fully under control, but delays in decision-making significantly affect effectiveness and usefulness of the implemented actions.
- “stabilization phase”, after the nuclear installation is returned to a controlled state, releases have stopped or the threat of their occurrence is prevented, when long-term measures need to be taken to overcome consequences of the accident.
During the “acute” phase, the risk of radiation exposure can be reduced by following the below recommendations:
- temporary sheltering inside buildings;
- self-evacuation, especially of children, pregnant women and nursing mothers;
- taking stable iodine drugs (only after relevant recommendations from the authorities);
- using personal respiratory protection means (respirators, cotton gauze bandages, dust cloth masks, etc.)
- meeting sanitary and hygienic rules.
The signal of prompt notification of the public on a nuclear or radiological accident at an NPP is the signal “ATTENTION TO ALL”, given by a klaxon, sirens of enterprises or signals of vehicles. This signal is a warning that an emergency has occurred and important information on it and required public actions will be transmitted soon. The broadcast takes place within 5 minutes after the sound signals. After having heard the signal “ATTENTION TO ALL”, it is required to:
- turn on the TV, radio, smartphone or other device allowing to receive further messages;
- listen to information on the situation and recommendations for actions during an emergency;
- close the windows and move away from them as far as possible;
- cut off gas and water supply;
- collect a supply of necessary belongings, medicine, food and drinking water (in case of evacuation), put important documents in a protective package;
- listen to information and follow recommendations for further actions.
- if you do not have gadgets at hand, you need to get to the nearest institution or establishment where television, radio or other means of information are available;
- follow the recommendations on the procedure of actions as presented in para 1.
In all cases, it is necessary to act quickly, remain calm, not to panic, provide assistance to disabled people, children and the elderly.
In addition to NPPs, specific risks represent unforeseen events that may occur anywhere at any time involving radiation sources that are beyond regulatory control, have been lost, stolen or have never been controlled or lost control (e.g. satellites parts or other space crafts).
Radiation accidents can potentially occur where radiation materials are used, stored or transported. However, the impact of such accidents is limited to the equipment, buildings and sites where the activities are carried out and does not pose a threat to the public.
What to do in case of an NPP accident
Hazards for the public from accidents at nuclear installations can arise only as a result of significant releases of radioactive substances into the environment. Therefore, the key goal of emergency management is to prevent the release of significant amounts of radioactivity by implementing the concept of multi-barrier protection. If at least one of the four barriers remains intact, the release prevention goal is achieved. At the last, fifth barrier level, emergency plans shall be activated to mitigate the effects of emergencies.
Depending on the emergency nature, the release of radioactive materials can be short-term or long-term (with intervals) from a few hours to a week or more.
The following main pathways are the main ones to form the human exposure dose:
- external gamma radiation from a radioactive cloud;
- external gamma radiation from radioactive material falling from the air to the ground;
- external beta and gamma radiation due to radioactive contamination of buildings, vegetation, clothing, skin;
- internal exposure from inhalation of radioactive substances with air;
- internal exposure from radioactive substances when consuming water and food contaminated with radionuclides.
External and internal exposure can be avoided or reduced by introducing urgent protection measures: sheltering, evacuation and blockage of the thyroid gland with stable iodine, as well as limitation of consumption of contaminated local foodstuff and water from open water reservoirs.
To limit the exposure risk it is necessary to follow the following recommendations:
- leave the event location as soon as possible and move to a safe distance recommended by the authorities or those who first took over the response function;
- when staying on the ground do not undress, do not sit on the ground, do not smoke;
- before entering a premise be sure to wash shoes with water or wipe with a damp cloth, shake outer clothing and clean with a damp brush;
- take a shower, change clothes at the first opportunity;
- when leaving the room, be sure to use personal protective equipment (respirator, dust bandage, raincoat, rubber boots, etc.);
- exclude swimming in open water.
- stay at home, in the office, in another premise if temporary shelter is recommended;
- seal the premise (close the windows, turn off the intake ventilation);
- perform daily wet cleaning of the premises, preferably with the use of detergents before receiving notification of stabilization or evacuation;
- strictly adhere to personal hygiene;
- do not use water from open sources and food, except in sealed packaging, protect food from dust;
- eat only indoors, before consuming food wash your hands thoroughly and rinse your mouth with a 0.5% solution of baking soda;
- control the radiation background (dose rate)
- listen carefully to notifications on development of the events and application of protection other response measures.
In all cases, it is necessary to follow recommendations of the competent authorities, attentively follow notifications via Internet, television and radio. Particular attention should be paid to the distance to the accident site and time spent close to the site; gamma radiation dose rate at the location according to the readings of personal dosimeter or monitoring networks. These data, as well as basic knowledge about the biological effects of radiation and assessments of trustworthy experts will help assessing how safe your situation is.
Main measures of radiation protection of the public
According to the up-to-date studies, international standards and methodologies of emergency preparedness and response, a severe accident with the nuclear fuel damage may require such urgent protection measures as evacuation and sheltering. These actions are combined with taking stable iodine. Urgent protection actions are supplemented with long-term ones, such as control of food stuff and water, relocation of the public from regions where the dose rate may lead to additional exposure during weeks and months due to radioactive fallout; decontamination of territory to reduce radioactive contamination level.
The methodology of the common European approach defines the following minimum zones and distances for planning protection measures:
- public evacuation should be prepared within 5 km around NPP, sheltering and thyroid gland blocking in radius up to 20 km;
- general strategy ensuring extension of the evacuation zone up to 20 km, sheltering and thyroid gland blocking up to 100 km shall be defined;
- radiation emergency monitoring and control of food stuff shall be planned at distances not less than 100 km with the possibility of extension up to 300 km;
Iodine prophylaxis (iodine blockade) is the blocking of the human thyroid gland, which consists in the immediate introduction into the human body of a drug with stable iodine to prevent or reduce the absorption of radioactive iodine isotopes by the thyroid gland in the event of a radiation accident.
What concerns emergencies at nuclear installations, exposure of personnel and the public with radioactive iodine will be the dominant factor in the first hours of the accident.
Iodine prophylaxis should be used only in the event of a nuclear accident with depressurization of nuclear fuel accompanied by emissions of iodine-131 and cesium-137 isotopes. The idea of this measure is to ensure that human body does not suffer a lack of iodine, which can otherwise be filled with its radioactive isotope entering into the body through the respiratory system.
For other types of radiation accidents, the iodine prophylaxis is not relevant and does not protect against exposure to other radionuclides.
The maximum protection effect (reduction of the exposure dose of the thyroid gland by 100 times) can be achieved if iodine agents are taken before radioactive iodine enters the body or simultaneously with it.
Agents for iodine prophylaxis are potassium iodide (in pills); potassium iodate, in their absence, aqueous-alcoholic solution of iodine can be used.
According to the Ukrainian legislation, iodine prophylaxis is used if the expected absorbed exposure dose of the thyroid gland from the accumulated radioactive iodine can exceed 50 milligray for children or 200 milligray for adults in accordance with the regulations established by the central executive body, which ensures formation of state policy in health care area.
Doses of stable iodine for single use recommended by WHO
Mass of iodine, mg
Mass of potassium iodide (Kl), mg
Mass of potassium iodate (KlO3) ), mg
Fraction of a tablet containing 100 mg of iodine
Fraction of a tablet containing 50 mg of iodine
Adults and adolescents (over 12 years)
Children (3-12 years)
Infants (1 month – 3 years)
Neonates (up to 1 month)
Source: Iodine thyroid blocking. Guidelines for use in planning for and responding to radiological and nuclear emergencies. World Health Organization, 2017
For the public living within a radius of 10 km around the NPP, the local executive authorities distribute potassium iodide preparation in advance in the amount of the daily need. The remaining stocks of preparations are stored in pharmacies, kindergartens and educational institutions, medical institutions, military units, penitentiaries and other places designated by the authorities.
The procedure for receiving preparations is communicated to the public during the notification on a radiation accident. The preparations can be distributed by special teams at delivery points, this can be home delivery, free delivery to pharmacies, and so on. The first intake of potassium iodide should be carried out immediately upon receipt of the notification on the release of radioactive substances and relevant instructions of the authorities, preferably, before the radioactive release arrives or within the first six hours after the absorption of radioactive iodine isotopes by the thyroid gland.
“Procedure for Implementation of Urgent Measures of Iodine Prophylaxis among the Population of Ukraine in the Event of a Radiation Accident”, approved by the SNRIU Order of 8 November 2011. The Regulations on Iodine Prophylaxis in Case of the Radiation Accident, approved by the Oder of the Ministry of Health No. 408 dated 09 March 2021.
Sheltering can be implemented faster than evacuation and does not require resources other than timely notification and announcement of recommendations. This measure is most effective for several hours during the release, but loses its effectiveness after one or two days.
According to the Law “On Human Protection against Impact of Ionizing Radiation”, measures to shelter people are applied if during the first two weeks after the accident the expected total effective radiation dose may exceed 5 mSv.
Basic types of specially equipped protective structures are shelters, which are sealed structures protection against the effects of many natural disasters, accidents and catastrophes, radiation shelters, which have slightly less protective properties than sealed shelters, and dual-use structures. These are ground or underground structures that can be used for the main functional purpose and to protect the public from emergencies. People need to arrive at the shelter with personal protective equipment, a two-day food supply in a plastic bag and essentials.
Interactive maps of the civil protection protective structures in settlements and in the territories of administrative units are available on the official websites of the Main Departments of the State Emergency Service of Ukraine and local executive bodies.
If it is not possible to take shelter in a specially equipped protective structure, it is necessary to stay in a building at the place of residence, work or temporary stay during the passage of the radioactive “cloud”, taking into account that wooden walls can reduce gamma radiation rate by two times, brick walls by ten times, basements with concrete roofing by 40-100 times. At the same time, it is necessary to follow official announcements and advices on further actions.
The Law of Ukraine defines that temporary evacuation of people shall be carried out if during the first two weeks after the accident the effective exposure dose can reach the level of 50 mSv. Timely and organized evacuation is an effective protection measure, but it brings discomfort to normal living conditions, is not always the best protection action and is used as an exceptional measure.
The public shall be notified of the time and procedure of evacuation by the management bodies of the territorial USCPS subsystem. In the conditions of radioactive contamination of the area, transport is delivered directly to entrances to protective structures and buildings, and people have to be boarded as soon as possible. During movement of the column, dose monitoring shall be performed.
Evacuation from the contaminated area shall be carried out in two stages. At the first stage, the public is transported to the boundaries of the contaminated zone. An interim evacuation point is organized there, registration, dose monitoring and decontamination of people being evacuated are carried out. After sanitation and decontamination of things, repeated dose monitoring shall be carried out and the evacuees are transported to the destination areas by “clean” transport at the second stage.
Evacuation is most effective measure if it can be completed before the release starts. If the release has started and is ongoing, it may also be effective, but the increased radiation risks of the evacuation conditions during long-term release should be taken into account. Evacuation is not recommended and will not have the expected effect if the release is over before its completion. Evacuation routes should always take into account wind direction and weather forecast.
The evacuation of the public after the Chornobyl accident started at 2:00 pm the next day, on 27 April 1986. By means of 1225 buses, 360 vehicles and 2 railway trains, 44,460 people were evacuated from the city of Pripyat within three hours (some inhabitants were evacuated using their private vehicles). The evacuation was carried out in two directions: most people were evacuated to Polissya Raion of Kyiv Oblast, a smaller part was placed in Ivankiv Raion. However, the evacuation organizers did not take into account the wind direction, which carried the radioactive cloud in western direction. Therefore, the residents of Pripyat, who were evacuated to Polissya Raion, received additional exposure doses.
On 3 May 1986, 15 villages in 10 km area from the Chornobyl NPP (about 10,000 persons) were evacuated, by 7 May another 43 settlements (including Chornobyl), and by the end of the year 188 settlements in total had been relocated from the 30-kilometer zone, what constituted about 116 thousand people (including Pripyat). That was how the Chornobyl Exclusion Zone was formed.
An example of evacuation well in advance were the decisions and actions of Fukushima Prefecture in Japan in 2011.
How one can learn about an accident?
- from mass media, social networks, mobile operators services;
- from official reports of the State emergency Service of Ukraine, State Nuclear Regulatory Inspectorate of Ukraine, nuclear operators on their official websites or from their statements to the mass media;
- from reports of local executive bodies, including alarm signals and loudspeakers.
What measures should be taken to reduce the risk?
- leave the event scene as soon as possible and move to a safe distance recommended by the police and other authorities who were the first to take over the response function;
- follow recommendations of the competent authorities of the country of residence, messages via the Internet, TV;
- take a shower, change clothes at the first opportunity if the event caught you outdoors;
- stay at home, in the office, other premises, if temporary shelter is recommended;
- do not drink water from open sources and food other than hermetically sealed;
- take a stable iodine preparation or an alternatively recommended number of alcohol solution drops only in the case of the announcement of iodine prophylaxis!;
- close windows, turn off the intake ventilation, do wet cleaning before receiving a notification on stabilization of the situation or evacuation;
- help those who need it, remain calm and keep common sense;
- consult a family doctor if in doubt or anxiety.
Options to estimate that you and your relatives are safe and factors to be accounted:
- distance from the event epicentre or time spent close to the event place;
- gamma radiation dose rate at the location according to readings of personal dosimeter or monitoring networks;
- information received from competent authorities and prediction of the event development;
- expert assessments you trust;
- basic knowledge of the biological effects of radiation.
Always use verified information from reliable sources!
Uatom.org Editorial Board