Radioactivity and Radiation

Home , Lux, Semiconductor detector, Synchrotron radiation

Flashlight

Light Ability to emit light

Unit for expressing strength of light [candle (cd)] Unit for expressing brightness [lux (lx)]

Radioactive Substance

Ability to emit radiation (radioactivity＊) Radiation

Unit for expressing strength of radiation Unit for expressing how much impact the radiation exerts [Sievert (Sv)] [Becquerel (Bq)]

＊May also be used to describe a substance (radioactive material) that is radioactive. 6 -1-1 ©JAERO Units Used in Relation to Radioactivity

Name Unit (Symbol) Definition

Unit of Radioactivity International System of Units (SI)

This unit represents the quantity of radioactive mate- Becquerel (Bq) Radioactivity rial in which one nucleus decays per second.

Unit of Radiation Dosage International System of Units (SI)

This unit represents how much energy is received by an object or person hit by radiation. A dose of 1 Gray Absorbed dose Gray (Gy) corresponds to 1 joule of energy absorbed by 1 kilogram of matter.

This unit is used for assessing how much risk radiation poses to people in terms of inducing cancer or Sievert (Sv) Dose genetic damage. (1 Sievert = 1,000 mSv)

Unit of Energy International System of Units (SI)

Unit of energy that represents the energy of radiation Joule (J) Energy (1J＝6.2×1018eV)

6 -1-2 ©JAERO Types of Electromagnetic Waves

10-15m 10-14m 10-13m 10-12m 10-11m 10-10m 10-9m 10-8m 10-7m 10-6m 10-5m 10-4m 10-3m 10-2m 10-1m 1m 10m 102m 103m (1Å) (1µm) (1mm) (1cm) (10cm) (1km) Wavelength 0.4µm 0.8µm (VHF) Gamma rays X-rays Ultraviolet Visible (UHF) (Generated from the nucleus) (Generated outside the nucleus) rays rays

Within X-rays there are things with rays Infrared wavelengths shorter than gamma rays Far infrared rays infrared Far Millimeter waves Ultrashort waves Short waves (HF) Short waves Centimeter waves Medium waves (MF) Medium waves Sub-millimeter waves Sauna Ultra high-frequency waves Ultra Microwaves

X-ray radiography X-ray Electric waves Synchrotron radiation Radar Contact-free thermometer AM radio TV (VHF) TV (UHF) Inhibiting potato germination Suntan and germicidal lamps Computed tomography (CT scan) Computed tomography Shortwave radio Shortwave Speciﬁc Examples FM radio, wireless FM radio, Fruit acidity and sugar content gauges Fruit Sterilization of medical equipment via irradiation Cell phones, microwave ranges microwave Cell phones, TV remote control, infrared camera, infrared heaters infrared camera, TV remote control, infrared Fluorescent lamp, incandescent lamp, visible laser light visible incandescent lamp, Fluorescent lamp,

1023Hz 1022Hz 1021Hz 1020Hz 1019Hz 1018Hz 1017Hz 1016Hz 1015Hz 1014Hz 1013Hz 1012Hz 1011Hz 1010Hz 109Hz 108Hz 107Hz 106Hz (1THz) (1GHz) (1MHz) Frequency

6 -1- 3 Source: Japan Atomic Energy Agency, What is Radiation? ©JAERO Properties of Radiation

Ionization Effect Fluorescence Effect Permeation

Fluorescent substance (inside the glass) Nucleus Atoms of gas (mercury) Electron

Pole Pole X-ray Generator Electron Ultraviolet rays

Radiation How Fluorescence Works When voltage is applied across the poles of the tube, electrons flow from one pole to the other. When electrons crash into mercury enclosed in the tube, it pro- duces ultraviolet light. The ultraviolet rays light up the fluorescent substance.

6 -1- 4 ©JAERO Types of Radiation

4 Alpha ray ( 2 He nucleus) (Ex.) α Alpha ( ) decay 226 α 222 88Ra 86Rn

Beta ray (electron) e (Ex.)

Beta (β) decay 24 β 24 11 Na 12 Mg

Gamma ray Gamma (γ) ray emission (electromagnetic wave)

Proton Neutron

X-rays...generated outside the nucleus Electromagnetic wave Gamma rays (γ)...come out of the nucleus

Beta rays (β)...electrons that escape the nucleus

4 Radiation Charged particles Alpha rays (α)...Helium- 2 atom nuclei that escape the nucleus Other

Uncharged particles Neutrons...generated in the use of nuclear reactors, accelerators and radio isotopes (radionuclide)

6 -1- 5 ©JAERO Permeability of Different Kinds of Radiation

Stops alpha rays Stops beta rays Weaken gamma and X-rays

Alpha rays (α)

Beta rays (β)

Gamma rays (γ) X-rays (X)

Paper Thin sheet of metal Thick board such as aluminum of lead and iron

Weaken Neutrons radiation

Neutron radiation

Substance containing hydrogen For example water or concrete

6 -1- 6 Source: Ministry of the Environment, Unified Basic Data on Health Effects from Radiation (FY2017) ©JAERO How Radiation Decays

Radioactive Substance Emitted Radiation＊ Half-life 1 Initial Level Thorium-232 α・β・γ 14.1 billion years Uranium-238 α・β・γ 4.5 billion years Potassium-40 β・γ 1.3 billion years Plutonium-239 α・γ 24,000 years

Carbon-14 β 5,700 years Radium-226 α・γ 1,600 years Cesium-137 β・γ 30 years Strontium-90 β 28.8 years Tritium β 12.3 years 1/2 Cobalt-60 β・γ 5.3 years Cesium-134 β・γ 2.1 years Half-life Level of Radioactivity Iodine-131 β・γ 8 days Radon-222 α・γ 3.8 days 1/4 Sodium-24 β・γ 15 hours Half-life 1/8 Half-life 1/16 Half-life (Time)

＊Includes radiation from products of decay (Nuclides that emit radiation and become a different nuclide.)

6 -1-7 Source: Japan Radioisotope Association, Radioisotope Pocket Data Book (2012) ©JAERO Radiation in our Daily Lives

Radiation Exposure (mSv)

We receive ＊1 2,500 to 6,000 mGy Infertility (gonads) 10000 doses of radiation in 3,000 to 5,000 mGy Temporary hair loss (skin)＊1 our daily lives from a variety of sources. ｍ From outer space 0.39 100 to 6,200 Gy Cardiac catherization (skin) 100 mSv or less 1000 Amount of radiation (mSv) exposure that bears 500 to 2,000 mGy no statistical difference in terms of the risk of cancer Lens becomes cloudy (eye)＊1 500 mGy Reduced blood-forming function (bone marrow)＊1 From the ground 0.48 Ramsar (Iran), Kerala, Chennai (India), 100 natural radiation from the ground 0.5 to 613.2 250 Limited to emergency workers ＊5 (No adverse impact to the health of residents found.) at power plants, etc.

50 Limit for workers at power plants, etc. (per year)＊4 10 From food 0.29 Natural radiation/person (per year) 2.4 2.4 to 12.9 CT (1 time) (World Average) 2.0 to 10 PET scan (1 time) 1 Natural radiation/person (per year) 2.1 3.0 Stomach X-ray (1 time) (Average in Japan) 1.0 Limit for the general public From radon in the air＊2 1.26 Flight from Tokyo to New York (excluding for medical treatment) (per year) (round trip) 0.08 to 0.11 ＊1：When discussing radiation hazards, it is expressed as 0.1 equivalent to an effective dose of 1 mSv, given that a dose of 1 mSv of gamma radiation is absorbed evenly by each part of the the entire body ＊： 2 Radioactive substances naturally present in the air 0.06 Chest X-ray in annual checkup (1 time) ＊3：Insignificant compared to naturally-occurring radiation levels, and the level does not require handling as 0.01 0.05 Targeted dose around a nuclear plant (per year) ＊ a radioactive substance that presents a safety risk. Clearance level 3 0.01 (year) ＊4：Dose of radiation that must not be exceeded in 1 year is 0.022 Estimated dose at reprocessing plant (Rokkasho) (per year) 50 mSV for workers at places such as power stations, or 100 mSv over 5 years. 0.01 Dental X-ray ＊5：The dose limit was raised to 250 mSv to emergency workers from April 2016 0.001 Less than 0.001 Actual emissions from nuclear power plant due to the revision of the Ionizing Radiation Hazard Prevention Regulations, etc.

Sources: United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 2008 Report, Nuclear Safety Research Association, 6 -2-1 Radiation in the Environment, New Edition, 2011, and ICRP, Publication 103, with others ©JAERO Doses of Radiation from Natural Sources

Annual dose/person (average in Japan) Annual dose/person (average worldwide)

From breathing From outer space (mainly radon) From outer space 0.3 0.48 0.39 re su e o ur xp s E o l p a x E n r I I l n n e a t t t e n e x

r r

From the ground r

n From breathing

x (mainly radon)

0.33 l

Annual dose of E Annual dose of E

x 1.26 x

natural radiation p natural radiation

From the ground s

(mSv) (mSv) u

r e 2.1 e 0.48 2.4

From food＊ 0.99 From food＊ 0.29

＊Compared to Western countries, the Japanese diet of seafood results in a larger effective dose due to Polonium-210.

Sources: United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 2008 Report, 6-2-2 and Nuclear Safety Research Association, Radiation in the Environment, New Edition, 2011 ©JAERO Differences in Natural Radiation Levels

Cosmic rays Offshore Gamma rays (γ) Wooden house (Kamakura)

6-story steel-reinforced building (lobby)

Underground mall in Ikebukuro

Ginza 3-4 Chome

Flight from Haneda to Osaka (5,000m)

International flight at high altitude 1.61 (11,000m)

0 0.05 0.10 0.15 （µSv/ｈ）

＊1µSv＝1/1000 mSv 1µSv/h=365 days x 24hours x 1,000=8.75mSv/year

6-2-3 Source: High Energy Accelerator Research Organization Radiation Science Center, Trivia about Radiation--Radiation in our Daily Lives, (2005) ©JAERO Naturally Occurring Radiation in the Body & Our Food

●Level of radioactive materials in the body (based on a Japanese person weighing 60kg)

Potassium-40 4,000 Becquerel Carbon-14 2,500 Becquerel Rubidium-87 500 Becquerel Lead-210/Polonium-210 20 Becquerel

●Level of the radioactive material Potassium-40 in food (Japan) (Unit: Becquerel/kg)

Dried kelp 2,000 Dried shiitake 700 Potato chips 400

Raw seaweed 200 Spinach 200 Fish100 Beef100

Milk 50 Bread 30 Rice 30 Beer 10

6-2-4 Source: Nuclear Safety Research Association, Study on Radiation Data in the Living Environment (1983), New Edition - Radiation in the Living Environment 2011 ©JAERO Various Uses of Radiation

Flow rate & velocity exams Non-destructive testing

Weld inspection Reinforced plastics

Thickness measurement

Regulating ripening Gauging

Selective breeding New drug development

Preventing germination

Study of compound structures

X-ray exams

X-ray CT scans Isotope batteries

Cancer treatment Uses of Radiation

6-2-5 ©JAERO Basics of Protection from Radiation

1. Protection via shielding 2. Protection via distance 3. Protection via time

Dose Rate = drops as the shield becomes thicker Dose Rate = inversely proportional to the distance Dose = (dose rate in work zone) X (working hours) Concrete

Distance

Radioactive material

(mSv/h) (mSv/h) (mSv) Dose Dose Rate Dose Rate

0 1 2 3 4 5 6 (cm) 0 1 2 3 4 5 6 (m) 0 0.5 1.0 2.0 (h) Concrete thickness Distance from radioactive material Working hours

6 - 3 -1 ©JAERO Effects of Radiation on Human Health

Acute disorders (erythema, hair loss)

Physical Impairment to fetal development (mental retardation) Deterministic effects Effects (tissue reactions) (thresholds＊ exist)

(Cataracts) Late-onset disorders

(Cancer, leukemia)

Stochastic effects (assuming no threshold＊ exists) Hereditary Inherited disorders Effects (congenital anomalies)

＊Threshold: value that constitutes a turning point at which a reaction occurs or not. 6-3-2 ©JAERO Symptoms from a Single Exposure to Radiation

Legend Body part Symptom mSv Local exposure Whole-body exposure

10,000+ Skin Acute ulcer 10,000

9,000 Whole body 100% of people die 8,000

7,000

6,000 Skin Erythema

Lens Cataracts 5,000

Gonads Permanent infertility 4,000 Whole body 50% of people die

Skin Hair loss 3,000

2,000

Lens Lens opacity 1,000 Whole body Nausea, vomiting (10% of people)

500 Whole body Reduced lymphocytes in peripheral blood

100 Whole body Clinical symptoms not confirmed

(Note 1) Deterministic effects (tissue reaction) are described, except for cancer and hereditary effects. (Note 2) General public dose limit is 1.0mSV/year, dose limit around a nuclear plant is 0.05mSV/year.

6-3-3 Source: Radiation Effects Association, Understanding the Effects of Radiation ©JAERO Acute Radiation Effects

Projected threshold※ estimates of the acute absorbed dose for 1% incidence of morbidity and mortality Gy (absorbed dose) Organ/Tissue Morbidity

Skin (large areas) Skin burns

Testes Permanent sterility Gastro-intestinal syndrome 6 Lungs Pneumonitis Small Intestine (with good medical care) Small Intestine Gastro-intestinal syndrome 5

Skin (large areas) Main phase of skin redding

4 Skin Temporary hair loss

Ovaries Permanent sterility 3

Bone Marrow Death (with good medical care) 2

Eye Cataract (visual impairment) 1.5

Bone Marrow Depression of blood-forming 1 Bone Marrow Death (without medical care) 0.5 ※Morbidity：Number of people who were afflicted with cancer, per population 0.1 Testes Temporary sterility Mortality：Number of people who died of cancer, per population Threshold：The maximum level of radiation considered to be acceptable or safe

6-3-4 Source: ICRP, Publication 103,118 ©JAERO Principles of Protection from Radiation

Below the threshold dose＊ for deterministic effects, the effect of radiation is suppressed and/or eliminated. For stochastic effects, the assumption is that there is no threshold dose below which radiation can be suppressed and be relatively certain that an adverse effect cannot occur.

[Deterministic effects (tissue reactions): hair loss, cataracts, etc.]

Threshold dose

Probability of Effects Probability 0 Dose No Effects

[Stochastic effects: cancer, leukemia, etc.]

Spontaneous incidence Assumption

Acceptable level

Probability of Effects Probability 0 Dose

＊Threshold dose: value that constitutes a turning point at which a reaction occurs or not.

6-3-5 Source: Radiation Effects Association, Understanding the Effects of Radiation ©JAERO The Difference between Exposure and Contamination

Exposure Contamination Radioactive materials Being exposed to radiation have adhered to matter, such as skin or clothes.

Radiation

Radioactive material

External exposure Internal exposure Contamination

6-3-6 ©JAERO The Relationship between Gray & Sievert Units

Sievert value = Gray value × Radiation weighting factor＊1 × Tissue weighting factor＊2

Energy unit mass Radiation Radiation

Sievert (Sv) Gray (Gy) This unit is used for assessing how much risk This unit represents how much energy was received by radiation poses to people in terms of an object or person hit by radiation. inducing cancer or genetic damage. A dose of 1 gray corresponds to 1 joule of (1 Sievert = 1,000 mSv) energy absorbed by 1 kilogram of matter. ◆Radiation weighting factor ◆Tissue weighting factor Types of Radiation Radiation weighting factor Tissue/Organ Tissue weighting factor Tissue/Organ Tissue weighting factor Photon (gamma or x-rays) 1 Breast 0.12 Esophagus 0.04 Red bone marrow 0.12 Thyroid 0.04 Electrons (beta rays) 1 Colon 0.12 Salivary gland 0.01 Proton 2 Lung 0.12 Skin 0.01 Alpha particles, fission fragments, heavy nuclei 20 Stomach 0.12 Bone surface 0.01 2.5-20 Neutron radiation (Determined by the continuous Gonads 0.08 Brain 0.01 function of energy) Bladder 0.04 Remaining tissues 0.12 ＊1： Represents the difference in effect according to the type of radiation. Liver 0.04 /organs ＊2： Represents how susceptible different tissues, such as internal organs, are to radiation.

6 -3-7 Source: ICRP, Publication 103 (2007) ©JAERO Conversion Method for Internal Exposure to Radiation (Committed Dose)

Committed Effective Dose Concentration of Food Intake Intake Days Dose Coefficient Radionuclides ＝ (kg/day) × (days) × × (mSv) (mSV/Bq) (Bq/kg)

Effective dose coefficient when 1Bq is taken orally or inhaled by an adult (mSv/Bq) Radionuclide Half-life Taken orally Inhaled

Plutonium-239 24,000 years 2.5×10-4 1.2×10-1

Cesium-137 30 years 1.3×10-5 3.9×10-5

Iodine-131 8 days 2.2×10-5 7.4×10-6

Strontium-90 29.1 years 2.8×10-5 1.6×10-4

Tritium＊ 12.3 years 4.2×10-8 2.6×10-7

＊The effective dose coefficient of tritium shows OBT (organically bound tritium), which is important for dosimetric evaluation, because it is easily absorbed by living bodies and has a long biological half-life. (Note) 1 is used for the market dilution factor (percentage of contaminated food intake relative to food intake of the evaluated subject) or for correction downwards, such as due to cooking. When more than one value is indicated for the nuclide of a chemical form, the largest effective dose coefficient is shown.

6-3-8 Source:ICRP “Publication 72”, Ministry of Economy, Trade and Industry “Tritiated Water Task Force Report (June 2016)” ©JAERO Evaluation of Internal Exposure to Radiation (Conceptual Diagram of Committed Dose)

The committed dose is deemed to be Intake of Radioactive Materials the dose over the first year, which was received during a set period after ingesting a radioactive material. The area of the yellow part is the dose of internal exposure. Dose of Internal Exposure Dose of Internal Exposure For adults For adults

0 50 years 0 1年 50 years Years after intake Years after intake

(Note) Adults : 50 years; children: from ingestion until 70 years old

6-3-9 ©JAERO An International Comparison of Food Reference Values

(Unit: Becquerel/kg)

Country Nuclide Japan U.S.A. EU Food group

Baby food 50 400

Milk 50 1，000 Radioactive 1,200 cesium Drinking 10 1，000 water

Foods in 100 1，250 general

Established dose of radiation will Established dose of radiation will Established dose of radiation will be less than 1 mSv per year. be less than 5 mSv per year. be less than 1 mSv per year. Values are calculated under the Values are calculated under the Values are calculated under the Principles of assumption contamination for assumption contamination for assumption contamination for Food Reference Values foods in general will be 50%; for foods in general will be 30%. foods in general will be 10%. drinking water and milk as well as baby foods, it will be 100%.

6 - 3 -10 Source: Ministry of Health, Labour and Welfare, New Reference Values for Radioactive Substances in Food ©JAERO Standard Principles for Protection from Radiation

[Normally] [After an Accident]

(a) Standards for avoiding excessive radiation in the aftermath of an accident Dose Refuge indoors: 10mSv Evacuation: 50mSv

(b) Standards in emergency situations (continuing accident) 20 to 100mSv/year

(c) Standards for exposure due to contamination Normally: 1mSv/year after an accident is resolved. Standards for keeping the 1 to 20mSv/year eﬀects of radiation to a mini- mum while a nuclear power plant is operating normally. Long-term goal: 1mSv/year

Days Elapsed Accident Occurs Accident Resolved

6 - 3 -11 Source: Nuclear Safety Commission materials ©JAERO Relative Cancer Risk Estimation for Radiation Exposure and Lifestyle Factors

(Targeted for Japanese between the ages of 40 and 69) Cancer Risk Factors from Exposure to Radiation Cancer Risk Factors related to Lifestyle

x1.80 Radiation exposure (1,000 - 2,000 mSv)

x1.60 Smoking, Drinking

x1.29 Underweight

x1.22 Obesity

x1.15-1.19 Lack of exercise※1 x1.19 Radiation exposure (200 - 500 mSv) x1.11-1.15 Too much salt intake x1.08 x1.06 Lack of vegetables※2 Radiation exposure (100 - 200 mSv) x1.00

(Note) Risk estimates for radiation exposure are based on the analysis of instantaneous dose effects in the case of A-bomb at Hiroshima and Nagasaki (solid cancer incidence only) and not based on the observations on prolonged dose effects. ※1 Lack of exercise: a very small amount of physical activity ※2 Lack of vegetables: vegetable intake is very low

6 - 3 -12 Source: National Cancer Center ©JAERO Radiation Dosages Received by Radiation Workers

(People) (mSv) 90,000 9.0 Legal Limit for Radiation--100mSv / 5 Years (However, 50mSv may not be exceeded in any 1 year) 80,000 8.0

Approx. 58,477

70,000 7.0 Number of Workers

60,000 6.0

50,000 5.0

40,000 4.0 Average Dose Average 3.5 3.1 Number of Workers 30,000 3.1 3.0 2.6 Average Dose 2.6 2.2 2.1 2.4 20,000 2.0 1.5 1.8 1.7 1.7 1.3 1.3 1.4 1.7 1.6 1.4 1.4 1.3 10,000 1.1 1.1 1.2 1.2 1.2 1.2 1.1 1.1 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 0.9 0.8

0 0.0 1980 85 90 95 2000 05 10 15 17 (FY)

＊ People who work with radiation at commercial nuclear power reactor facilities.

Source: Nuclear Regulation Authority, 2017--Status of Managing Dosages of Radiation Workers at Commercial Power Reactor Facilities, Research and Development Stage Power Reactor Facilities, 6 - 4 -1 Processing Facilities, Reprocessing Facilities, and Nuclear Waste Disposal Facilities, October 2018, with others ©JAERO Controls in a Nuclear Power Plant by Area

Entrance

Guards Classified in detail according to the extent of Entrance radiation or contamination

Guards Entrance

Guards Control is especially needed to preserve a nuclear power plant Controlled Area

(except a controlled area). Protected Area

Monitoring Area

Within the area, unnecessary entry of the general public is restricted to prevent them from being exposed to Protected Area more doses emitted from nuclear Controlled Area facilities than regulated by laws.

Monitoring Area Nuclear Power Plant Entry is restricted to prevent amage by radiation and radioactive materials.

Radiation Control Flow

Section responsible Radiation workers for an assignment Experts in radiation control Medical examination / Education / Making a work plan Exposure records check

Controlled-area entry permit Setting dose equivalent target

Carrying a portable individual dosimeter Measures to reduce To instruct radiation exposure radiation (ex. Installation of shields) protection To wear protective clothing (wearing a protective mask, if necessary)

Work within a controlled area Surface contamination test to check workers' body

Completion of work

Left : Glass badge Right : Alarm-equipped dosimeter Surface contamination test

Individual effective dose is measured by the entrance and exit control equipment. Measure and evaluate individual effective dose

Recording measurement results and notifying individuals about them

Registering the data to the Radiation Employees with protective clothing working Dose Registration Center for Radiation Workers Radioactive materials in the body are periodically checked by a whole body counter.

Effective Dose Limit Equivalent Dose Limits Category (Whole Body) (Tissues and Organs)

100mSv/5 years＊1 Lens of eyes 100mSv/5 years＊1, 50mSv/year＊2 and 50mSv/year＊2 Normally Females 5mSv/3 months＊3 Skin 500mSv/year＊2 Pregnant women 1mSv Pregnant women 2mSv Radiation (Internal exposure until birth) (Abdominal surface until birth) Workers

① 100mSv Lens of eyes 300mSv/year Emergency＊4 ② 250mSv Skin 1Sv＊5

General Lens of eyes 15mSv/year＊2 Normally 1mSv/year＊2 Public Skin 50mSv/year＊2

(Note) The values in the table above are total doses of external and internal exposure. (They do not include naturally occurring radiation or exposure during medical procedures.) ＊1：Classification every 5 years after April 1, 2001 ＊2：One year starting April 1 ＊3：Every 3 months, starting on the 1st of April, July, October and January ＊4：• Engaging in emergency work on equipment and facilities, etc. targeted by the Act on Special Measures Concerning Nuclear Emergency Preparedness is restricted to workers in occupations that involve radiation exposure who have received information pertaining to radiation exposure in advance and have expressed their intention to take part, and who have received the necessary training. • Regulated limits on radiation exposure are governed in the two stages of ① the conventional effective dose of 100 mSv, and the addition of ② an effective dose of 250 mSv in the event of there being a high probability of radioactive materials being discharged outside of the site. ＊5：1Sv (Sievert) =1,000mSV (milli-Sieverts) = 1 million Sv (micro-Sieverts)

6-4-4 Source: Created from the notiﬁcation to establish dose limits in accordance with the provisions of the ordinance on activity of reﬁning nuclear source or nuclear fuel materials, etc. ©JAERO Migration of Radioactive Materials in the Environment

Released into the Air

Deposited onto Nuclear Facility Soil and Plants

Crops Animal Products

Open Water and Water Table

Flow from Rivers Falls onto Tap Water Lake Surface Fresh Fish Products

Seafood

Discharged into Ocean

Monitoring Station

Measures weather data along with radiation containing in Environmental Sample dust particles floating in the Collection (Land) air, in addition to measuring Monitoring Car environmental radiation Sample of vegetable leaves, milk, soil, rain, and river water, etc., are collected to measure Carrying equipment for radioactivity measuring radiation and radioactivity, it travels in wide area for monitoring

Monitoring Area Environmental Sample Nuclear Facility Monitoring Post Collection (Sea)

Fish, shellfish, seaweed and Environmental radiation is seawater, etc. are sampled to continuously measured measure radioactivity around nuclear facilities

10km Urban area 5km

Milk Milk Station

3km Turban shell

Ag. Products Ocean floor (Rice, leafy and root vegetables) Floating dust

Soil Seawater Monitoring post and TLD post Highway Seaweed, sargassum Nuclear Power Plant ＊ Drinking water TLD post Fish Meteorological stations Pine needles Seaweed, sargassum

Seawater Seawater radiation monitoring Monitoring stations

＊TLD： Thermoluminescence dosimeter Milk Urban area Some substances emit light if they are heated after being subject to radiation. A TLD dosimeter uses this to measure radiation.

Station

Geiger Counter

Window (Mica or mica-film) Current － Battery + Meter

Resistance Pulse output Counting circuit + ++++ Condenser －－－－－ Positive ion Negative ion Insulator Radiation Center Metal Argon gas, etc. wire wall (+pole) (-pole) Ionization chamber Scintillation Detector Aluminum Shaded case case － Current Reflective Transparent Magnetic seal Battery material window Air

1 to 9 dynodes Meter Radiation Fluorescence

Radiation Photo-electron Photomultiplier tube

Positive ion + Photoelectric Focusing Anode Negative ion Scintillator (sodium iodide single crystal) surface electrode

(Note) It is necessary to measure microcurrents in the range of 10-9～10-14 with the ionization chamber. When fluorescence strikes the photoelectric surface of the scintillation detector, electrons are kicked out and this is multiplied by the dynodes (multiplier electrodes), which allows a greater electrical signal to be obtained.

6 - 5 -1 Source: Japan Atomic Energy Agency, Nuclear Power Basic Glossary, (1997) ©JAERO Classifications of Radiation Measurements

Gas-flow proportional counter tube type Alpha rays ZnS scintillation type, etc. Measurement of alpha rays Surface Contamination Beta rays Plastic scintillation type For testing contamination of bodies, the ground, etc. (gamma) Geiger counter type, etc.

Gamma rays Nal/Csl scintillation type Mainly measures low-level radiation

Geiger counter type Measures low to mid-level radiation

Ionization chamber type Measures low to high-level radiation Ambient Radiation Ge/Si semiconductor detector Spectral analysis and nuclide identification Level

Neutron 3 radiation, etc. HE proportional counter tube type Neutron radiation

Beta rays Ionization chamber type Measures low to high-level radiation

Si semiconductor detector External exposure Glass dosimeter Measures the cumulative dose attached to the surface of the body Individual Level Individual track detector, etc. of Exposure Nal scintillation type Measures the outside of the body via a whole body Internal exposure Ge/Si semiconductor detector, etc. counter or biological sample measurement (bioassay)

ZnS scintillation type, etc. (measures alpha rays)

Radiation Screening

Geiger counter type (measures beta rays)

Monitoring Post Survey Meters

Scintillation Ionization Chamber Detector Detector

NaI Scintillation type CsI Scintillation type, etc. (mainly measures low-levels) (mainly measures low-levels)

Ionization Chamber 3He Counter Tube type (measures low to high-level radiation) (measures neutron radiation)

Measuring External Exposure Measuring Internal Exposure

Electronic Dosimeter (personal dosimeter) Whole Body Counter

[Example of Use] [Example of Use]

Workflow using a germanium ①Sample dissection ②Dry at high temp ③Carbonize/turn to ash semiconductor detector at super high temp

①Sample dissection ↓ ②Dry at high temp ↓ ③Carbonize/turn to ash at super high temp ↓ ④Pressure form ↓ ⑤Measure gamma rays ↓ ⑥Pulse height analysis ④Pressure form ⑤Measure gamma rays ⑥Pulse height analysis

Cesium-137 Potassium-40

Count of Radiation

Energy of Radiation