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Banana radiation (equivalent dose) calculator

Put any radiation dose in perspective with the Banana Equivalent Dose — the tiny ~0.1 µSv you get from the potassium-40 in one banana. Enter a dose in µSv, mSv, Sv, mrem or rem and it converts to bananas, standard units and a plain-language risk band.

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Enter Radiation dose, Dose unit and the Banana radiation (equivalent dose) calculator works out Banana equivalent doses (BED), Dose, Dose, Dose, Risk band straight away. For instance, with Radiation dose = 100 and Dose unit = microsieverts (µSv) it returns Banana equivalent doses (BED) = 1,000 bananas, Dose = 100 µSv and Dose = 0.1 mSv.

How to use it

  1. Enter your values: Radiation dose, Dose unit.
  2. Read the result instantly: Banana equivalent doses (BED), Dose, Dose, Dose, Risk band.

Frequently asked questions

How does the Banana radiation (equivalent dose) calculator work?

It takes Radiation dose and Dose unit and derives Banana equivalent doses (BED), Dose, Dose, Dose and Risk band from them. The calculation is live as you type, so the result updates on every change.

Which values does the calculator ask for?

2 values: Radiation dose and Dose unit. Nothing else is required — no account, no file upload.

What does a typical calculation look like?

With Radiation dose = 100 and Dose unit = microsieverts (µSv), the calculator returns Banana equivalent doses (BED) = 1,000 bananas, Dose = 100 µSv and Dose = 0.1 mSv. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

How much does the result change with different inputs?

It moves a lot. Using Radiation dose = 200 and Dose unit = millisieverts (mSv) instead, Banana equivalent doses (BED) goes from 1,000 bananas to 2,000,000 bananas — which is why it is worth testing a few scenarios rather than trusting a single figure.

Which “Dose unit” option should I choose?

You can pick between « microsieverts (µSv) », « millisieverts (mSv) », « sieverts (Sv) », « millirem (mrem) » and « rem ». Each one changes what the calculator works out, so switch and compare — the default is « microsieverts (µSv) ».

What does it give for smaller values?

Scaled down to Radiation dose = 0 and Dose unit = microsieverts (µSv), Banana equivalent doses (BED) comes out at 0 bananas. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Checking a homework answer, sizing something before building it, and getting an order of magnitude before committing to a design — a torque on a bolt, the force a spring returns, the frequency a circuit resonates at, how long light takes to arrive.

What is the most common mistake?

Feeding in a value in the wrong unit. Physics formulas assume SI throughout, so grams instead of kilograms or centimetres instead of metres shifts the answer by powers of ten without any warning.

How accurate is it, and what are the limits?

For scale: 1 banana ≈ 0.1 µSv · dental X-ray ≈ 5 µSv · transatlantic flight ≈ 40 µSv · chest X-ray ≈ 100 µSv · annual natural background ≈ 3000 µSv (3 mSv) · abdominal CT ≈ 7000 µSv · lowest yearly dose clearly linked to cancer ≈ 100000 µSv (100 mSv). Educational only; the BED is a rough illustrative unit, not a clinical measure.

What is the difference between the Banana radiation (equivalent dose) calculator and the Heat transfer rate calculator?

This one returns Banana equivalent doses (BED) and Dose; the Heat transfer rate calculator returns Heat transfer rate Q (W) and In kilowatts (kW). That is the whole difference — open the one whose figure you need.

Further reading

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