Radiation Safety Practice Exam

What is the half-life of Americium-241?

1. 8 days

2. 12.3 years

3. 458 years

4. 4.5 billion years

The correct answer is: 458 years

The half-life of Americium-241 is approximately 432.2 years, which is commonly rounded to about 12.3 years in educational contexts. This means that after 12.3 years, half of a given amount of Americium-241 will have decayed into a different element, specifically Neptunium-237. This characteristic makes Americium-241 particularly relevant in applications such as smoke detectors and certain types of batteries, as its relatively short half-life provides a consistent source of radiation without the long-term hazards associated with isotopes having significantly longer half-lives. It’s important to understand the implications of half-lives in the context of radiation safety. Knowing the half-life helps in assessing the long-term risks of exposure to radioactive materials, the management of radioactive waste, and determining safe handling procedures. Americium-241's half-life signifies that while it is stable enough for use in various applications, it will not persist indefinitely, thereby requiring careful monitoring and management over time.