The Univ. of Tokyo

Takeshi IIMOTO, PhD

Basics of

Radiation and its Risks for Teaching Radiation to

Secondary Level Students

Naturally Occurring Radioactive Materials

NORM with high radioactive concentration

include monazite, phosphate ore, titanium ore

and other minerals and mineral sands that are

widely used as industrial raw materials.

Technologically Enhanced Naturally

Occurring Radioactive Materials

Additionally, products made from these materials

are applied to a wide range of fields and also

used as consumer goods by many people.

Natural environment with high dose

Raw materials: mineral ore…

Waste rock, soil, sand

Ash, Scale, Sludge: produced by industries

Radioactive Spa

Consumer Goods, …

Radiation is existing anywhere

and the level is varying !

Ｎａｔｕｒａｌ Ｕ，Ｔｈ，Ｋ...

Olympic Dam

- Copper, Gold and Uranium mine-

(1) Crushing & milling facility

(2) Copper facility

(3) Piling up of tailings, from refinery

Phosphate fertilizer industry

(combined with uranium refining industry)

• Inside of facility

• Entrance of facility

• Surface dose rate of drying drum:

around 0.2 μSv/h

up to 1.0 μSv/h inside

Natural Spa

Artificial Spa

← Bedding, Futon

Underclothes, Lingerie ↓

Negative Ion Goods

17

1920s ◦ Low cost green glass

- U with iron ◦ Called depression glass

1959 – used depleted U until 1972

For example, US-NRC allows up to 20% by weight

◦ About 14% - most ever used

◦ A plate could have 4.5 g of U

Health apparatus →

↑artificial hot spring

Incandescent

gas mantle → ↑ Bottle

including Ra

Powder

0.5

1.0

1.5

0

Total Dose (mSv)

Ｒｅｌａｔｉｖｅ Ｓｏｌｉｄ

Ｃａｎｃｅｒ

Ｒｉｓｋ

200 400 600 800 1000

Nair et al, Health Phys 96, 55 (2009)

Hiroshima & Nagasaki Atomic Bomb Survivors

India High-BG Residents

Preston et al, Radiat Res 168, 1 (2007)

References

An Example Time Schedule of Two hours radiation education programme for junior high students

Part I Lecture (60 min)

5 min - Program explanation (purpose, lectures…)

45 min - Basic radiation lecture (presented by radiation expert)

+ Radiation and dose surrounding us

+ Radiation use in industry, medical, agri,..

+ Radiation type

+ Radiation and Radioactivity

+ Half life

+ Unit of Bq and Sv

+ Human effect of radiation

+ Radiation protection

(Using this lecture duration, supporters are

preparing for the Part II experiments in the

experimental room.)

10 min - Breaking time

Part II Two Experiments (60 min)

20 min - Cloud chamber observation (One chamber for two, or at best one chamber for four)

+ Pouring ethanol (only); 5 min

+ Cooling time by dry ice; 5 min

+ Observation; 10 min

30 min - Environmental survey by Hakaru-kun

(One Hakaru-kun for two, or at best one for four)

+ Instruction to use Hakaru-kun; 5min

It is possible to use the cooling time of

cloud chamber. It is very reasonable.

+ Surveying activity; 25 min

10 min - Conclusion

[p50, p52]

[p31]

[p31]

Web platform on Radiation Education Information; “RADI”, http://www.radi-edu.jp/, which includes

◦ instructional material

◦ movie guides

◦ columns of experienced experts

◦ Example pictures & illustrations

◦ Example PPT presentations

◦ Example education class movies

for class use, in Japanese version.

Anybody can use the material available in the website after completing a registration requirement (no charge)

Several materials translated in English can be used through

RADI-English website http://www.radi-edu.jp/en/

[p31] Activity to Support Teachers on Radiation Education

Movies Web platform on Radiation Education Information; “RADI”

- 20 min movie

- Q&A attractive talk-show between

- students and an expert

- Focusing on the radiation keywords

- in junior high school textbook

- Showing the movie to students in place of teachers’ explanation

- 5 min short movie ×6 stories

- Movie instruction manual on experiments

- Preparation for experiment, or showing these movies to students

in the class in place of doing experiments

- English subtitles are ready. ★ Let’s see example movies.

- 1 - 2 min short movie × 16 stories

-One by one explanation on basic keyword

-Teachers can select their target keywords

for the purpose

Let’s try radiation experiments by yourself !

Basic lecture on radiation

Short stories on radiation

◦ Theme (1)

Cloud Chamber

- Let’s observe tracks of

radiation

◦ Theme (2)

Measurement of Natural

Radiation

- Let’s measure radiation

using “Hakaru-kun

(Mr. Gamma)”

Theme (1)

Theme (2)

Effective Use of Radiation in Various Fields

- 30 min movie, recommended officially by MEXT in 2010

- Junior high school students reports the real situation of

radiation usage in industry, medical, agriculture,

archaeology, and other fields.

- Radiation-related experiments by experts

- Q&A attractive talk-show between students and an expert

- Showing the movie to students in place of teachers’

explanation

Radiation Application

1) A lot of skilled experts to support schools and teachers are needed. “Skilled” means not only on the level of knowledge on radiation or experience of use of radiation, but also on the teaching experience and communication ability. Let’s select adequate and attractive candidate and start to train them as soon as possible.

2) Let’s prepare education materials (handouts, PPT materials, work sheets, experimental tools etc.) and their instruction documents for teachers, and distribute them, which can be directly used by teachers in their classrooms.

3) Showing and opening real radiation/nuclear sites to teachers and/or students is one of the best experiences for them to be interested in radiation. Let’s establish the systematic framework to accept them into each institution or university.

4) It is very difficult to teach high-level science contents to teachers and students. Radiation risk is one of the most difficult items in radiation education. Not only radiation experts, but risk communicators or social scientists should also join the discussion to prepare the education materials.

1) It is important to clarify the purpose of radiation education in Malaysia. Education system, strategy and vector would be established based on this information.

2) Based on the purpose of radiation education shown by the government, the education agency should prepare the national standard text book of radiation for school education like Supplementary textbooks of Japan. For the physical point of view of radiation education, the agency should determine the adequate contents and range. In addition, social science viewpoint on radiation, for example on a part of the story of radiation risk, is also important. However, this area needs careful discussion among well-arranged experts to prepare and write the national standard book. Occasionally the transparency of process and reason of selection of experts could be an important point to be discussed in public.

3) National framework or system to support teachers is needed to perform attractive radiation education. Radiation experiment in classroom costs. Teachers and schools need funds. Information web platform like RADI is also effective. Instruction movies, teaching materials, model education programs, etc, could be shared among teachers and experts through this website.

4) Simplified radiation dose-meter like Hakaru-kun (Mr. Gamma) is effective for radiation education. The nuclear/science agency should establish nation-wide distributing system of detectors to all schools by cooperated with institutes or university.