Question 1: Explain the difference between irradiation and contamination in the context of radioactivity.

Answer: Irradiation occurs when a person is exposed to radiation from a source without the source being on or in contact; contamination involves radioactive material being physically present on or inside the body.

Question 1: Define 'radioactive contamination'.

Answer: Radioactive contamination is the presence of radioactive substances on or inside an object or person.

Question 2: Describe how irradiation can occur during medical X-ray procedures.

Answer: Irradiation occurs when a person is exposed to X-ray radiation from the machine without any radioactive material being transferred to them.

Question 1: A worker is exposed to a radiation dose of 5 millisieverts (mSv) during a procedure. If the recommended safe limit per year is 20 mSv, what fraction of the limit has the worker reached?

Answer: 0.25

Question 2: Calculate the activity (in Becquerels) of a radioactive source emitting 1000 disintegrations per second. (Use activity = disintegrations per second).

Answer: 1000 Bq

Question 1: List three safety precautions that should be taken when handling radioactive materials to prevent contamination.

Answer: Use protective clothing, work in designated areas, and avoid direct contact with radioactive sources.

Question 2: Describe a simple experiment to demonstrate the difference between irradiation and contamination.

Answer: One could use a radioactive source to expose an object without contact (irradiation) and then place radioactive material on the object to show contamination, explaining the different exposure mechanisms.

Question 1: A person enters a room where radioactive dust has settled on surfaces. They receive a dose of radiation primarily due to contamination. Explain the main difference in health risk between this situation and being near a radioactive source emitting radiation without contact.

Answer: Contamination involves radioactive material on or inside the body, which can cause internal damage if ingested or inhaled, while exposure to radiation without contact mainly affects external tissues.

Question 2: In a nuclear medicine procedure, a patient receives a dose of radioactive material internally. Is this an example of irradiation or contamination? Justify your answer.

Answer: This is an example of contamination because radioactive material is inside the body, but it also involves irradiation as the patient is exposed to radiation from the internally placed source.

Question 1: Describe how radioactive contamination is managed in nuclear power plants to ensure safety.

Answer: Radioactive waste is carefully contained, stored in secure facilities, and monitored regularly to prevent leaks, minimizing contamination risk.

Question 2: Explain why radioactive sources used in medical treatments are carefully shielded and handled with protective equipment.

Answer: To prevent contamination and unnecessary irradiation exposure to healthcare workers and patients, shielding and protective gear reduce radiation exposure.