Interactive Half-Life Calculator
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A thing’s half-life is how long until only half of it is left. It’s used in radioactive decay, medicine, and many other things. Remember:
- Hazards in radiation are proportional the rate at which energy comes out.
- Short half-lives imply energy is coming out quickly, and are the primary hazard.
- Long half-lives imply energy is coming out very slowly, and are less of a hazard. For example, you can hold long half-life isotopes of natural uranium in your hand without accumulating a hazardous dose.
- In the extreme, an infinite half-life would mean energy never comes out, representing zero radiological risk.
Learn more about the math here.
This graph depicts a single nuclide with its single half-life decaying to stability. Nuclear waste is typically composed of thousands of different nuclides that each have their own unique half-life, and often decay to other radioactive daughter nuclides before making it to stability.
Learn about solutions to nuclear waste here.