Calculator
Formula used
This calculator uses a practical altitude model for dose rate:
D(h) = D0 × e^(h/H) × F_lat × F_solar × F_shield
- D(h) is dose rate at altitude h in µSv/h.
- D0 is the sea-level dose rate (µSv/h).
- H is a scale height (m) controlling the exponential rise.
- F_lat increases with absolute latitude (geomagnetic shielding proxy).
- F_solar accounts for solar-cycle modulation of cosmic rays.
- F_shield applies a user-defined reduction (1 − shielding%/100).
Note: this is an estimation model. Real dose depends on route, atmosphere, storms, and aircraft conditions.
How to use this calculator
- Enter altitude and choose the correct unit.
- Set latitude for your location or typical route.
- Select solar activity, or enter a custom multiplier.
- Enter exposure time and its unit (minutes, hours, or days).
- Add shielding reduction if you have a known factor.
- Click Calculate. Results appear above this form.
- Use Download CSV or Download PDF for records.
Example data table
| Altitude (m) | Latitude (deg) | Solar | Shielding (%) | Estimated dose rate (µSv/h) |
|---|---|---|---|---|
| 0 | 45 | average | 0 | 0.0625 |
| 2,000 | 45 | average | 0 | 0.1438 |
| 5,000 | 45 | average | 0 | 0.5019 |
| 11,000 | 45 | average | 0 | 6.1150 |
Cosmic radiation dose and altitude guide
1) Why altitude changes dose
Cosmic rays are high‑energy particles from space. As altitude increases, the atmosphere provides less shielding. That thinner air lets more secondary particles reach you, so dose rate rises rapidly with height.
2) A practical dose model
Many field estimates treat altitude as an exponential gain: D(h) = D0 × e^(h/H). Here, D0 is a baseline dose rate near sea level and H is a scale height. This approach matches the “fast increase” seen above mountain elevations.
3) Typical ranges you can expect
A common background range at sea level is about 0.03–0.07 µSv/h. Around 2,000 m, many locations land near 0.10–0.25 µSv/h. Near 5,000 m, values can approach 0.3–1.0 µSv/h. Commercial cruise altitudes near 11,000 m often fall in the 2–6 µSv/h range. Over a year, small hourly differences add up, which is why flight crews track cumulative exposure. For everyday context, 1 mSv equals 1,000 µSv, so short trips are usually reported in µSv.
4) Latitude and Earth’s magnetic shielding
Earth’s magnetic field deflects charged particles. Near the equator, shielding is stronger, so dose is typically lower than at high latitudes. Polar and sub‑polar regions generally show higher exposure, especially at flight levels. The latitude factor in this calculator approximates that trend for planning and comparison.
5) Solar activity effects
During strong solar activity, the solar wind can reduce incoming galactic cosmic rays, lowering average dose rates. During quiet periods, dose can be higher. Short‑lived solar particle events can increase exposure at aircraft altitudes.
6) Shielding and environment
Buildings, vehicles, and terrain can reduce dose by blocking some particles. Aircraft cabins provide partial shielding but not full protection. Use the shielding percentage to test “what‑if” scenarios for structures or barriers.
7) Turning dose rate into total dose
Total dose equals dose rate multiplied by time. For example, 3 µSv/h over a 5‑hour flight gives about 15 µSv. Repeating a route weekly can produce a noticeable annual total. Use the time unit options to convert minutes, hours, days, or weeks for planning.
8) Interpreting results responsibly
This tool is an educational estimator, not a personal dosimeter. Real dose depends on altitude profile, route, weather, geomagnetic conditions, and aircraft specifics. Results are best used for comparisons, like “mountain site versus coastal site” or “mid‑latitude versus polar route.” For compliance or safety decisions, follow national guidance and professional monitoring where required.
FAQs
1) Is cosmic radiation higher on airplanes?
Yes. At cruise altitude there is less atmospheric shielding, so dose rate rises. Long flights at high altitude and high latitude can add measurable micro‑sievert doses.
2) What baseline dose rate should I use?
If you do not have local data, many users start with 0.05 µSv/h for sea level. You can adjust it to match local background measurements or published regional averages.
3) Why does latitude matter so much?
Earth’s magnetic field deflects charged particles more strongly near the equator. Polar routes have weaker magnetic shielding, so average dose rates can be higher than equatorial routes.
4) Does solar activity always reduce the dose?
Often it reduces average galactic cosmic ray dose. However, rare solar particle events can temporarily increase exposure at altitude. This calculator uses simple scaling, not event forecasting.
5) What does “shielding percent” represent?
It is a simple reduction factor for barriers like buildings or materials. It is not material‑specific. Use it for scenario testing, not for certifying a design or a protective product.
6) Is this the same as radon exposure?
No. Radon is a terrestrial radioactive gas and varies by geology and ventilation. Cosmic radiation comes from space and increases with altitude, especially above mountainous and flight elevations.
7) Which unit should I choose, µSv or mSv?
Use µSv for short periods like a flight or a day. Use mSv for larger totals, such as cumulative dose over months. The calculator converts between them automatically.