Resources: Class presentation and handout.
Handout: List some sources of background radiation. Explain the factors that may change the background radiation a person receives. Use data to assign the amount of radiation received to the source and make calculations to assess the overall risk.
What sources of natural and man-made background radiation can you identify? Ask the students to identify when they think they were last exposed to radiation. Introduce them to cosmic radiation and radon gas.
Use the handout to establish an understanding of how much annual background radiation the average human is exposed to and when the dose levels are too high. Use the problems to reinforce learning.
Some of the problems will require research online and some estimation of hours - such as the question for the pilot on long-haul flights. The graph is for students to answer with their knowledge and then discuss the results as given in the answer sheet.
Go online to ukradon.org and explore the interactive radon map – write notes to explain why some areas of the country have higher levels of radon gas.
Learn how to use a Geiger-Müller counter and find out what the normal levels are in the environment.
What other occupations may put people at an elevated risk of exposure to higher levels of radiation?
Career Film: This is Colin Fairbairn. Colin works as a Senior Technologist for National Nuclear Laboratory.
Expert Film: This is Emin Veron, who works as a Fuel Performance Scientist for National Nuclear Laboratory. Emin explains the uses of radiation.
Ask the students to use the handout to summarise the man-made and natural sources of radiation. Describe why different people receive different amounts of background radiation. Research the background levels of radiation in some sources and discuss the relative risk. Make an estimate for the amount of background radiation a person may receive in their job from given data and describe any assumptions made. Use a graph to sign a type of background radiation.
Challenge Task:
“Cornwall remains a silent and invisible killer across the county with some people dwelling in homes that pose a greater risk of radiation absorption than if they were working in a nuclear plant.“
This statement is from CornwallLive online: https://www.cornwalllive.com/news/cornwall-news/radon-invisible-killer-gas-over-5931134
Discuss this statement. Can the students find data to prove/refute this? Should people in Cornwall be worried? How can any risk be reduced?
Complete the summative quiz on the presentation to assess learning. Why do flight crew receive radiation (background)? What precautions do they take? Should they take more? (Flight crews on high latitude flights receive more radiation annually than a nuclear plant worker! However, there are no standards and limits on length of exposure.)