Formell Modellering och Verifiering av EAP-NOOB Protokollet

The expansion of the Internet of Things (IoT) has resulted in an increasing number of new devices communicating independently over the network with each other and with servers. This has created a need for protocols to manage the swiftly growing network. Consequently, formal verification methods have become an important part of the development process of network systems and protocols. Before implementation, the specification itself has to be shown to be reliable and secure. Nimble out-of-band authentication for EAP (EAP-NOOB) is a protocol for bootstrapping IoT devices with a minimal user interface and no pre-configured credentials. In this thesis, we create a symbolic model of the EAP-NOOB protocol with the mCRL2 modelling language and verify both its correct operation and its liveness properties with exhaustive state space exploration and model checking. Major findings relate to the recovery of the protocol after lost or corrupted messages, which could be exploited for denial-of-service attacks. We contribute to the standardisation process of the protocol by model checking the current draft specification and by suggesting improvements and clarifications to the next version. Finally, we verify the changes made to the protocol and show that they improve the overall reliability and fix the detected issues. Moreover, while modelling the protocol, we found various underspecified features and ambiguities that needed to be clarified. Furthermore, we create a test suite for testing the cryptographic implementation. By comparing message logs from the implementation with output generated by our test script, we find that incompatibilities between cryptographic libraries sometimes resulted in protocol failures.Utvidgandet av sakernas internet (IoT) har resulterat i en ökning av nya fristående apparater som kommunicerar med varandra och med servrar. Detta har skapat ett behov av protokoll för att upprätthålla det växande nätverket. Följaktligen har användning av formell verifiering blivit en viktig del av utvecklingsprocessen av nätverkssystem och protokoll. Innan ett protokoll implementeras, måste själva specifikationen bevisas vara pålitlig och säker. Nimble out-of-band authentication for EAP (EAP-NOOB) är ett protokoll för koppling av IoT-apparater med ett minimalt användargränssnitt och inga förhandskonfigurerade kreditiv. I detta examensarbete skapar vi en symbolisk modell av EAP-NOOB-protokollet med mCRL2 språket och verifierar diverse egenskaper genom tillståndsutforskning. Vi bidrar till protokollets standardiseringsprocess med förändringsförslag, visar att de förbättrar protokollets tillförlitlighet och korrigerar de upptäckta problemen. I samband med verifieringsprocessen hittade vi diverse tvetydigheter i specifikationen som korrigerades. Ytterligare presenterar vi ett testprogram för kryptografisk verifiering och datagenerering. Genom att jämföra loggfiler från implementeringen med våra genererade data visar vi att det existerar inkompatibiliteter mellan kryptografiska programbibliotek

The Role of International Criminal Courts in the Formation of Customary International Law

Tämä tutkielma tutkii nykyisten kansainvälisten rikostuomioistuimien roolia kansainvälisen tapaoikeuden muodostumisessa. Tutkielma käsittelee sovellettavaa lakia ja oikeuskäytäntöä entisen Jugoslavian alueen ja Ruandan sotarikostuomioistuimissa (ICTY ja ICTR), Sierra Leonen erikoistuomioistuimessa (SCSL) sekä pysyvässä kansainvälisessä rikostuomioistuimessa (ICC). Tutkielma vastaa erityisesti kysymyksiin, minkälainen rooli kansainvälisellä tapaoikeudella on oikeuslähteenä edellä mainittujen tuomioistuimien oikeuskäytännössä sekä toisaalta, missä määrin nämä tuomioistuimet ovat vaikuttaneet kansainvälisen tapaoikeuden muodostumiseen. Kansainväliset rikostuomioistuimet toimivat tärkeinä tekijöinä kansainvälisen tapaoikeuden olemassaolon ja sisällön määrittäjinä. Vaikka näiden tuomioistuimien ensisijainen tehtävä on soveltaa lakia, eikä luoda sitä, niiden oikeuskäytäntö muodostaa keskeisen osan kansainvälisen tapaoikeuden muodostumisprosessia. Lainsäädäntövallan ja tuomiovallan yhdistäminen yhdeksi prosessiksi on kuitenkin omiaan tuhoamaan oikeuskäytännössä syntyneiden sääntöjen legitiimiyden. Varsinkin yksilön rikosvastuun laajentaminen lainkäyttövaiheessa tulkitsemalla rikosten tunnusmerkistöä ja määritelmiä laveasti on koettu ongelmalliseksi. Rikosoikeudellinen laillisuusperiaate kieltää nimenomaisesti taannehtivan lainkäytön ja rankaisemisen. Tämä näyttäisi kieltävän myös sen, että tuomioistuin voisi jälkikäteen laajentaa yksilön rikosvastuun alaa oikeuskäytännössään. Tästä huolimatta kansainvälisten rikostuomioistuimien laintulkinnat ovat olleet tässä suhteessa huomattavan innovatiivisia läpi kansainvälisen rikosoikeuden historian. Tämä työ tarkastelee erityisesti kansainvälisen tapaoikeuden muodostumisprosessia kansainvälisten rikostuomioistuimien oikeuskäytännössä. Se tutkii tapaoikeuden ja oikeudellisten ratkaisujen välistä vuorovaikutusta ja selvittää kuinka tapaoikeuden traditionaalinen ja moderni teoria suhtautuvat kansainvälisiin tuomioistuimiin tapaoikeuden muodostajina. Lopuksi työ analysoi kriittisesti kuinka nykyiset kansainväliset rikostuomioistuimet ovat identifioineet kansainvälisen tapaoikeuden sääntöjä. Tarkastelemalla oikeudellisissa ratkaisuissa käytettyjä metodeja ja argumentteja se tutkii ovatko kansainväliset rikostuomioistuimet täyttäneet laillisuusperiaatteen asettamat vaatimukset tuomiovallan käyttäjälle. Tutkielman pääargumentti on, että kansainväliset rikostuomioistuimet toimivat kansainvälisen tapaoikeuden muodostamisprosessin ytimessä ja osallistuvat tapaoikeuden kehittämiseen vahvasti. Näiden tuomioistuimien myötävaikutus kansainvälisen rikosoikeuden sisältöön on ollut korvaamaton. Kansainvälisessä rikosoikeudessa vallinnut juridinen luovuus näyttää kuitenkin vähenevän tulevaisuudessa, sillä lähes yksinomaan tapaoikeutta soveltaneet Jugoslavian ja Ruandan ad hoc tuomioistuimet ovat lopettamassa toimintansa, ja vahvasti kirjoitettuun lakiin tukeutuva ICC saa toimia suunnannäyttäjänä tulevaisuuden kansainväliselle rikosoikeudelle.This thesis examines the role that contemporary international criminal courts play in the formation of customary international law. It addresses applicable law and the case law of the International Criminal Tribunal for the former Yugoslavia (ICTY) and Rwanda (ICTR), the Special Court for Sierra Leone (SCSL), and the (permanent) International Criminal Court (ICC). More specifically, this thesis provides answers as to the role customary law plays as a source of applicable law in these courts and further, the role these courts play in developing the content of customary law. International criminal courts serve as important entities in discovering and interpreting existing rules of customary international law. Although these courts’ primary function is to apply existing law, not to create it, their case law forms an essential part of the formation process of customary international law. But uniting the legislative and judicial processes together diminishes the legitimacy of the resulting rules. The problem comes to the fore when international criminal courts broaden the scope of individual criminal liability by expanding the definitions of international crimes. The principle of legality –inherent to criminal law– prohibits retroactive crime creation and punishment and thus seems to prohibit courts from interpreting law expansively. However, throughout the history of international criminal law international criminal courts have been remarkably productive in their interpretations. This thesis examines the role of customary law in the practice of contemporary international criminal courts. It elaborates on the interplay between customary law and judicial decision and examines how traditional and modern approaches to custom formation deal with international courts as entities capable of forming new rules of customary law. Finally, it analyzes critically how rules of customary law have been discovered and identified in contemporary international criminal courts. By addressing the methods and arguments used in judicial reasoning it examines whether international criminal courts have fulfilled the requirements of the principle of legality in their work. The main argument of this thesis is that international criminal courts operate in the very heart of the customary law-making process. Their contribution to the corpus of international criminal law has been indispensable. However, the judicial creativity practiced by the modern international criminal courts seems to be on the decline as the ad hoc Tribunals (ICTY and ICTR) are concluding their work and the ICC begins to lead the way for the future application of international criminal law

Sienipohjaiset materiaalit

Opinnäytetyössäni esittelen tutkimustani sienipohjaisista materiaaleista. Kyseisten materiaalien käyttö on vielä uutta ja sisältää paljon potentiaalia sekä mahdollisuuksia, joita ei olla toistaiseksi hyödynnetty.Sienipohjaisista materiaaleista on mahdollista tehdä loputon määrä erilaisia materiaaleja. Valmista tietoa sienimateriaaleista on vielä hyvin vähän, joten opinnäytetyöni perustuu pääosin omaan tutkimukseeni

Randonneur pyörä - Kevytrakenteinen teräksinen polkupyörä

The main goal of the thesis is to design a fast and lightweight bicycle as an assignment. The aim is to use technical solutions that have been found to be functional and durable over a long period of time. My work also examines existing bike models and speculates what kind of bike model is currently missing from the markets. At the beginning of my thesis, I describe my research and define the research question: 1. What makes a good steel-framed bicycle for longer trips and everyday commuting? 2. Which factors give this bicycle model a competitive advantage over other models, so that it is feasible to be produced in small series? In addition to the written research material, theoretical structure of this thesis consists of different stages of user research. ‘User in Product Development’ design procedure consists of several different steps. Different modes of work complement each other, and they are often used in overlapping ways. For example, based on the designers’ own experience, a preliminary model is created, which is then observed in experimental use. The design, manufacturing and analysis of the preliminary prototype have important roles in my thesis. It is necessary to produce a prototype which is matches the mass-produced version as accurately as possible, especially when it comes to studying the handling and behavior of a bicycle. Considering the practical design work and economic reasons, it is justified that the prototype is produced locally. Hence, I make all the necessary tools to produce the frame, as well as the first working prototype myself, which facilitates further design work. At the end of my thesis, I present the first preliminary bicycle model, and analyze it’s functionality through user research. I also ponder on how the project will continue after my thesis.Opinnäytetyöni keskeisin tavoite on suunnitella toimeksiantona nopea ja kevytrakenteinen polkupyörä. Tarkoitukseni on hyödyntää pitkässä käytössä toimivia ja kestäviksi todettuja teknisiä ratkaisuja. Työni tarkastelee tämän lisäksi jo olemassa olevia pyörämalleja, sekä millainen pyörämalli puuttuu tällä hetkellä markkinoilta. Opinnäytetyöni alussa taustoitan tutkimusta ja määrittelen tutkimuskysymyksen: 1. Mitkä tekijät vaikuttavat teräsrunkoisen polkupyörän soveltuvuuteen niin pidemmille matkoille kuin jokapäiväiseen käyttöön? 2. Mikä tekee suunnittelemastamme mallista kilpailukykyisen muihin olemassa oleviin malleihin verrattuna, jotta sitä on järkevä tuottaa piensarjana? Kirjallisen tutkimusmateriaalin lisäksi käytän suunnittelutyössäni apunani käyttäjätutkimuksen eri vaiheita, jotka täydentävät toisiaan. Suunnittelijoiden oman kokemuksen perusteella luodaan alustava malli, jonka kokeellista käyttöä sitten seurataan. Alustavan protomallin suunnittelu, valmistus ja analysointi ovat isossa roolissa opinnäytetyössäni. Tutkittaessa polkupyörän ohjattavuutta ja käyttäytymistä on valmistettava runko ja kokoonpano, jotka vastaavat mahdollisimman hyvin tulevaa sarjatuotantomallia. Käytännön suunnittelutyön ja kustannussyiden takia on järkevämpi, että pystymme jatkokehittämään mallia opinnäytetyöni jälkeen lähellä. Tämän takia valmistan itse kaikki tarvittavat työkalut rungon valmistusta varten ja toteutan ensimmäisen toimivan protomallin. Opinnäytetyöni lopussa esittelen ensimmäisen alustavan polkupyörän mallin ja analysoin sen toimivuutta käyttäjätutkimuksen kautta. Tämän lisäksi pohdin projektin jatkoa ja toimintasuunnitelmaa

Consequence assessment of nuclear-powered vessel accidents and floating nuclear power plant transit accidents in the Arctic region

Radiological consequence assessment of atmospheric releases of radioactive materials due to accidents on Nuclear-Powered Vessel (NPV) and during a transit of Floating Nuclear Power Plant (FNPP) were performed. The assessment was performed using a probabilistic approach for open sea locations in the Gulf of Finland and near the Norwegian coast in the Barents Sea, and coastal locations nearby the city of Tromsø and the Kara Strait on the Northern Sea Route. The dose rates and radiation doses to emergency workers and people close to the accident site were estimated, and needed protective actions were evaluated. The decision support system JRODOS was used to model the dispersion and deposition of radioactive substances in atmospheric release and to estimate dose rates and the doses to people and emergency workers. The modelling applied previously published radionuclide inventories and release fractions, and NOMADS weather data from the year 2021. The results showed that for the NPV accidents, external dose rate of 100 μSv/h, effective dose of 100 mSv, and thyroid equivalent dose of 100 mSv are exceeded nearby the accident locations. Thus, in case there is habitation in the vicinity of the scene, different protective actions are needed downwind from the accident location to protect people. It was estimated that the recommendation to limit being outside is needed up to 10 km, sheltering indoors up to 3 km and evacuation up to 2 km. Furthermore, the iodine prophylaxis for adults may be needed up to 5 km, and rough estimate revealed that iodine prophylaxis for children and pregnant females is needed up to 10 km. Based on the analyses, emergency workers should wear Personal Protective Equipment (PPE) up to about 5 km from the accident site due to the elevated external dose rates. Furthermore, the emergency workers should take iodine prophylaxis if the air contains radioactive iodine, working hours should be recorded, and alarming external dose rate meters and dosimeters should be used. In prolonged situations, the shift work arrangements should also be considered up to 1 km to limit total working time. It is not likely that the higher Operational Intervention Levels (OIL) of 1000 or 10000 μSv/h are exceeded in the considered NPV accident. In the FNPP transit accident, the effective and thyroid equivalent doses remain below 0.1 mSv and 1 mSv, respectively. Furthermore, the external dose rate of 1 μSv/h was not exceeded in any of the analyzed release scenarios. It was concluded that it is highly unlikely that any of the protective actions would be needed for the people or emergency workers due to the considered atmospheric releases from the considered FNPP transit accident. Note that the results given are dependent on initial assumptions and are likely to change with assumptions. Työssä arvioitiin ydinkäyttöisen aluksen (NPV) onnettomuuksien ja kelluvan ydinvoimalaitoksen (FNPP) kuljetusonnettomuudesta aiheutuvan radioaktiivisen ilmakehäpäästön seurauksia. Seurausarvio tehtiin hyödyntäen tilastollisia menetelmiä Suomenlahdella ja Barentsinmerellä Norjan rannikolla sekä Tromsøn ja Karan salmen alueilla Pohjoisella merireitillä. Annoslaskennan perusteella arvioitiin päästön aiheuttamaan ulkoista annosnopeutta sekä pelastushenkilöstön ja väestön mahdollista säteilyaltistusta. Lisäksi arviointiin mahdollisien suojelutoimien tarvetta. Päästön leviämis- ja laskeumamallinnus sekä annoslaskenta suoritettiin käyttäen JRODOS -ohjelmistoa. Mallinnuksessa hyödynnettiin aiemmin julkaistuja tietoja laivareaktoreiden radionuklidi-inventaarille ja päästöosuuksille sekä globaalia NOMADS-säädataa vuodelta 2021. Tulokset osoittivat, että NPV-onnettomuuksissa ulkoinen annosnopeus ylitti 100 μSv/h ja efektiivinen ja kilpirauhasen ekvivalentti annos ylittivät 100 mSv onnettomuuspaikan läheisyydessä. Jos alueella on asutusta, tuulen alapuolella onnettomuuspaikan lähellä tarvitaan erilaisia suojelutoimenpiteitä ihmisten suojelemiseksi. Arvioitiin, että suositus ulkona olon rajoittamisesta tarvitaan 10 km:iin, sisälle suojautumiseen 3 km:iin ja evakuoimiseksi 2 km:iin saakka. Lisäksi joditabletteja tarvitaan aikuisille 5 km:iin sekä lapsille ja raskaana oleville 10 km:iin saakka. Arvioiden perusteella säteilytyöntekijöiden tulisi käyttää henkilökohtaisia suojavarusteita noin 5 km etäisyydelle saakka onnettomuuspaikasta korkean ulkoisen annosnopeuden takia. Lisäksi hätätyöntekijöiden tulisi ottaa joditabletti, jos päästö sisältää radioaktiivista jodia, työtunnit tulisi kirjata ja ulkoisen annosnopeuden mittareita ja dosimetrejä tulisi käyttää. Pitkittyneissä tilanteissa työaikaa alle 1 km etäisyydellä tulisi rajoittaa hyödyntäen työvuoroja. On epätodennäköistä, että päästön seurauksena ylittyisi korkeammat ulkoisen annosnopeuden toimenpiderajat (1000 tai 10000 μSv/h). Havaittiin, että FNPP-onnettomuudessa efektiivinen annos jää alle 0,1 mSv:n ja kilpirauhasen ekvivalentti annos jää alle 1 mSv:n. Analyysin perusteella, ulkoisen annosnopeuden arvo ei ylittynyt 1 μSv/h minkään analysoidun päästön seurauksesta. Voidaan todeta, että on epätodennäköistä, että FNPP-onnettomuuden seurauksena mikään asetetuista annosrajoista tai ohjeellisista toimenpiderajoista ylittyisi laitoksen ulkopuolella

Security Analysis of the Consumer Remote SIM Provisioning Protocol

Remote SIM provisioning (RSP) for consumer devices is the protocol specified by the GSM Association for downloading SIM profiles into a secure element in a mobile device. The process is commonly known as eSIM, and it is expected to replace removable SIM cards. The security of the protocol is critical because the profile includes the credentials with which the mobile device will authenticate to the mobile network. In this paper, we present a formal security analysis of the consumer RSP protocol. We model the multi-party protocol in applied pi calculus, define formal security goals, and verify them in ProVerif. The analysis shows that the consumer RSP protocol protects against a network adversary when all the intended participants are honest. However, we also model the protocol in realistic partial compromise scenarios where the adversary controls a legitimate participant or communication channel. The security failures in the partial compromise scenarios reveal weaknesses in the protocol design. The most important observation is that the security of RSP depends unnecessarily on it being encapsulated in a TLS tunnel. Also, the lack of pre-established identifiers means that a compromised download server anywhere in the world or a compromised secure element can be used for attacks against RSP between honest participants. Additionally, the lack of reliable methods for verifying user intent can lead to serious security failures. Based on the findings, we recommend practical improvements to RSP implementations, to future versions of the specification, and to mobile operator processes to increase the robustness of eSIM security.Comment: 33 pages, 8 figures, Associated ProVerif model files located at https://github.com/peltona/rsp_mode

A coaxial probe with a vertically split outer sensor for charge and dimensional measurement of a passing object

A coaxial induction probe with a vertically split outer sensor for simultaneously measuring the charge, distance, and size of a passing object is presented. When a charged sphere passed the probe, current signals of different shape induced to all the sensors. The signals were integrated, and Gaussian curves were fitted. The amplitudes and widths of the fitted curves were used to calibrate the set-up. The experimental calibration was done by using frictionally charged spheres of different sizes. Spheres with unknown size, distance, and charge were measured using the calibrated sensor. However, the speed of the object needed to be known. The results from computer simulations, calibrations, and use in measurements are presented.</p

Stronger response of farmland birds than farmers to climate change leads to the emergence of an ecological trap

Climate change is triggering adaptation by people and wildlife. The speed and magnitude of these responses may disrupt ecological equilibria and potentially cause further biodiversity losses, but this has rarely been studied. Species inhabiting human-dominated landscapes may be particularly negatively affected by human adaptations to climate change. This could be, for example, the case of ground-nesting farmland birds, a group of highly vulnerable species that may be impacted by shifts in the timing of mechanical farming operations in response to climate change. Here we aim to explore whether trends in phenology of breeding ground-nesting birds differ from those of farming practices, and whether differences lead to the emergence of phenological mistiming with detrimental consequences to the birds. To achieve our objective, we tan linear mixed effects models using a 38 year dataset on onset of farming practices (i.e. sowing dates) and laying date of two endangered ground-nesting farmland birds (Northern lapwing and Eurasian curlew) in Finland. We found that timing of farming practices advanced slower than birds nesting phenology, with birds progressively starting nesting before fields are sown. These nests are at high risk of destruction from incoming sowing operations. The results highlight the importance of considering human adaptation responses, in addition to those of wildlife, for implementing species conservation in managed landscapes under climate change.Peer reviewe

Potential consequences of hypothetical nuclear power plant accidents in Finland

An assessment of the environmental consequences of radioactive releases from severe reactor accidents was performed for Finnish nuclear power plants (NPP) in operation (Loviisa 1 and 2, and Olkiluoto 1 and 2), in commissioning (Olkiluoto 3) and in the preparatory phase (Hanhikivi 1). Three hypothetical radioactive releases (Basic, Large and Very Large cases) with different magnitudes were considered. Basic case represents a release corresponding to the limit set in requirements for severe reactor accidents, and thus, the other two represent extremely unlikely situations where severe accident management has failed. The magnitude of Very Large case is similar to the Fukushima NPP accident and roughly one order of magnitude smaller than the Chernobyl NPP accident, while the magnitude of Large case is roughly one order of magnitude smaller. The environmental assessment on the consequences of the releases was performed using a probabilistic approach. The aim is to estimate radiation doses to the population around the NPP and land contamination resulting from the release of radioactive material. The results of the assessment were compared to the protective action criteria for radioactive release from an NPP, and further used to evaluate the sufficiency of the Precautionary Action Zone (PAZ) and Emergency Planning Zone (EPZ) given in Finnish regulation. The probability of exceeding different operational intervention levels (OIL) and dose criteria set for external dose rate, effective dose, thyroid dose, deposition of strong gamma emitters, deposition of cesium, and concentration of gamma emitters in the air were estimated for distances up to 300 km from each site. Dispersion and deposition of releases were modelled with the dispersion model SILAM of the Finnish Meteorological Institute. The modelling applied historical weather forecast data from the years 2012–2015 retrieved with operative weather forecast models AROME and HARMONIE. Dose rates and doses were determined from the radionuclide air concentrations and depositions with the threat assessment tool TIUKU. The assessment was preformed using 2920 dispersion realizations for each reactor type and release scenario. For the assessment, the 95th percentile of the modelled dispersion, deposition and dose data was selected. The assessment showed that it is unlikely that any OILs or dose criteria would be exceeded outside PAZ and EPZ in a Basic case. In a Large case, the OILs may be exceeded up to about 110 km from the NPP sites, while it could be up to 170 km for dose criteria for the recommendation to limit being outside and iodine prophylaxis for children and pregnant females. The assessment indicated that it is unlikely that sheltering indoors or evacuation are needed outside the PAZ and EPZ during the early phase of the emergency due to the release in a Large case. In a Very Large case, extensive protective actions including permanent or temporary relocation are needed outside EPZ and less restrictive protective actions (i.e., recommendation to limit being outside and iodine prophylaxis for children and pregnant females) are needed beyond the area considered in this study (> 300 km). It was shown, however, that the protective actions outside the PAZ and EPZ are strongly dependent on prevailing weather conditions. It was observed that the dose criteria for an adult’s effective and thyroid dose were exceeded in larger areas than suggested by the criteria based on the external dose rate. Furthermore, dose criteria for a child’s thyroid dose were exceeded in larger areas than the dose criteria for the recommendation to limit being outside, even though the iodine prophylaxis for children and pregnant females is set as a complementary protective action for the recommendation to limit being outside. The observation demonstrates that the content of the radioactive release must be carefully considered in a severe NPP accident as the amount of released iodine isotopes affect the thyroid dose, while other nuclides make only a small contribution to it. It was also observed that precipitation may cause the deposition of radioactive substances such that in large areas the criteria for protective action based on deposition may be exceeded, even when protective actions would not be warranted according to dose criteria for effective doses. In Large and Very Large cases, the deposition may lead to the need for decontamination of large areas, and temporary or even permanent relocation of people. These findings demonstrate the importance of primarily using dose criteria in decision making if dose calculations can be performed reliably during the actual nuclear or radiological emergency. The OILs shall be used only if measures with dose criteria cannot be determined reliably e.g., due to a lack of information. Based on the results, it was concluded that further study is needed to set an Extended Planning Distance (EPD) and Ingestion and Commodities Planning Distance (ICPD). In such a study, a level 2 Probabilistic Risk Assessments (PRA) considering the probability of atmospheric releases should be better linked with environmental consequence assessment. The International Atomic Energy Agency (IAEA) recommends the EPD and ICPD to facilitate preparedness planning and the execution of protective actions beyond the PAZ and EPZ. The existence of an EPD and ICPD could also improve the effective co-operation of different authorities and emergency workers in a nuclear emergency. In Large and Very Large cases, the seasonal variations between summer and winter were found to be significant especially when considering deposition of cesium and strong gamma emitters. It was observed that precipitation during the winter season causes more wet deposition than in the summer. In a Very Large case, the seasonal variations were also significant in other measures

Environmental Radiation Monitoring in Finland : Annual report 2020

This report is a national summary of the results of environmental radiation monitoring in Finland in 2020. In addition to the Radiation and Nuclear Safety Authority, results to the report has been provided by the Finnish Meteorological Institute regarding the total beta emission activity of outdoor air. The environmental radiological monitoring programme includes the continuous and automatic monitoring of the external dose rate, monitoring of radioactive substances and total beta activity in outdoor air as well as the regular radioactivity analysis of radioactive fallout, surface and domestic water, waste, milk and foodstuffs. The programme also includes the monitoring of radioactive substances within the human body and monitoring of the radon in indoor air. This report also includes summaries of the results of the Baltic Sea radioactivity monitoring and topical investigations of the sub-programmes part of environmental radiation monitoring. The 2020 results demonstrate that the artificial radioactive substances in the environment mostly originate from the Chernobyl disaster in 1986 and nuclear tests conducted in the atmosphere in the 1950s and 1960s, and the amount of these substances is decreasing in the living environment. During 2020, artificial radioactive substances were detected in outdoor air, especially in samples collected in Kotka. However, detections were also made at all other collection stations. In early March, several fission and activation products were detected in samples collected in Kotka and Imatra. At the end of April, the iodine isotope 131I was detected in a sample collected in Kotka. In mid-June, several activation and fission products were again detected in samples collected in Kotka and Helsinki. In July, the cobalt isotope 60Co was detected in a sample collected in Kotka. In early August, an isomer of the silver isotope 110mAg was detected, and in late August the caesium isotope 134Cs, both from samples collected in Kotka. 60Co and 131I were again detected in a sample collected in Kotka between September and October. In early December, 131I was widely detected, and was found in all samples except Helsinki. The origin of the August silver discovery was determined to be the Loviisa nuclear power plant. The origins of the other observations could not be established with certainty. The amounts of all the artificial radioactive substances observed during the year in outdoor air were extremely small and they do not have any impact on human health. The external radiation monitoring network worked well. Of the measuring station results, the external radiation monitoring data management system USVA collected more than 97% of the measurements produced at all measuring stations. Missing data was caused by equipment malfunctions or telecommunication problems. In 2020, the GM sensors of the monitoring network issued nine alarms. Three of the alarms were caused by radiographic testing. Three alarms occurred on the same day caused by exceptionally heavy rainfall in September in Western Finland. Two alarms were caused by measurement activity training with radiation sources, and the cause of the other one was unknown. No alarms came through the spectrometer network. The tritium contents in fallout and household water samples were small, in total 1 – 2 Bq/l. No 137Cs activity concentrations exceeding 600 Bq/kg were found in food samples. This concentration should not be exceeded when putting wild game, berries, mushroom and lake fish on the market. 137Cs from the Chernobyl disaster, natural radioactive substances and radioactive substances used at hospitals were observed in waste. Secretions from patients in the cancer clinics and isotope wards of hospitals using radionuclides migrate to wastewater treatment plants and are thus evident in waste. The radiation exposure caused by artificial radioactive substances in the environment in 2020 was under 0,02 mSv, which is low compared to Finns’ overall average dose of 5,9 mSv. The 2020 results demonstrate that there were no releases of radioactive substances into the environment during the year that would have any detrimental impact on human health or the environment in Finland. The primary source of radon (222Rn) in indoor air is the rock material containing uranium in the soil. High radon concentrations occur in buildings whose foundations are not sufficiently well sealed to prevent the entry of radon-carrying soil air. Radon is most effectively prevented by measures taken at the construction stage, i.e. by building the base floor structures to be leak-tight and installing radon piping under the floor slab. According to STUK’s measurements, radon concentrations in the indoor air of dwellings are lower than before. In 2020, the median for radon concentration in residential measurements was 95 Bq/m3 (2019 109 Bq/m3) and the average 188 Bq/m3 (2019 222 Bq/m3), and 17% (2019 21%) of measurements were greater than the reference value of 300 Bq/m3. The concentration values from the national radon database, which stores STUK’s radon measurement results from dwellings, overestimate the radon concentration values, because more measurements are carried out in the known areas of high radon concentration than in areas of low radon concentrationThe radon dose assessment method in indoor air changed in late 2018. Applying the new assessment method, the radon dose value in homes is 4 mSv per year while the previous method estimated the dose at 1,6 mSv annually. The determination of the average annual radiation dose to Finns is discussed in STUK publication STUK-A263 Suomalaisten keskimääräinen efektiivinen annos vuonna 2018 (The average effective dose received by Finns 2018)