Radiation, noise and UV-A calculator for pilots: 3 yearly estimates

Pick your aircraft, the routes you fly most and your block hours for a year. The calculator runs the three Health models in the Off Chocks app and gives a yearly cosmic radiation dose, your cockpit noise dose and your UV-A load, each with its working.

How the radiation estimate is worked out

The aircraft sets the cruise level, from the app's table of usual levels for each type: FL370 for the A320, FL380 for the 737-800 and FL390 for the A350, for example. Change it if you fly higher or lower.

Dose rate rises with the square of the flight level. At the geomagnetic pole the model starts from 3.8 × 10⁻⁵ × FL² microsieverts an hour, a published fit of aircrew dose against flight time and altitude (Quiñonez and Quimbay, arXiv:1812.02073). At FL370 that comes to 5.2 µSv an hour.

The Earth's magnetic field turns away more cosmic rays at low latitudes, so the model multiplies the polar rate by 0.35 at the geomagnetic equator, rising to 1.0 at the geomagnetic pole. It measures geomagnetic latitude from the dipole pole of the IGRF-14 field model for 2025, at 80.8° N and 72.8° W, so the figure differs from the latitude on your chart: Sydney sits near 40° geomagnetic and 34° geographic, London near 53° and Singapore near 8°.

The Sun matters as well. An active Sun keeps more galactic cosmic rays away from the Earth, and the model swings the dose by up to 25 percent each way over an 11-year cycle counted from the December 2019 solar minimum. The same flying reads lowest in 2025 and about 55 percent higher in 2030 than in 2026. Real cycles vary in length and strength.

Each route kind uses one geomagnetic latitude: the average the app's model gives a set of real routes, sampled along the great circle the way the Health page samples each flight you log.

How the noise estimate is worked out

Each aircraft type carries a typical cockpit level at the pilot's ear with no headset, from the app's table: about 76 dB(A) in airline jets, 84 in turboprops, 92 in piston aircraft and 95 in helicopters. A headset takes 12 dB(A) off with passive ear cups and 20 with noise cancelling.

In an airline jet the radio and intercom set a floor under the headset, because a headset cannot quieten what plays inside it: 83.5 dB(A) with no headset or a one-ear set, 80 with passive cups and 77 with noise cancelling. The figures come from measurements on airline flight decks (Lower and Bagshaw, Internoise 96; Muller and Schneider, BMJ Open 2017).

The dose follows the NIOSH method. Eight hours at 85 dB(A) makes one reference day, and every 3 dB(A) more halves the time it takes to get there. Below 80 dB(A) the model counts nothing. The app shows the year's dose spread over every calendar day.

How the UV-A estimate is worked out

Cockpit windshields block most UV-B, but some UV-A gets through, and UV-A grows with height. The app adds about 9 percent per 1,000 metres, so at FL370 the same sun carries about 2.6 times its sea-level UV-A. The calculator multiplies your daylight hours by that factor and shows the result as hours of the same sun at sea level, behind the same windshield.

That is a comparison, not a dose. Real cockpit UV-A depends on the glass, the side windows and the height of the sun on each sector, and only your logged routes and times can show those. The app walks every logged flight's route in five-minute steps and counts only the minutes the sun is up.

What the estimate leaves out

• Solar particle events. A large solar storm can add dose on polar and high-latitude sectors, and nobody can predict one, so the model leaves them out.
• Climb, descent and taxi. The model applies your cruise level to every block hour, so for short sectors, which spend more of their block time below cruise, the estimate leans high.
• Your own aircraft and headset. The noise table holds one typical level per type, and your seat, airframe and headset volume change it. Outside airline jets no published level under a headset exists, so the estimate there may read low.
• The real sun. The UV-A comparison treats every daylight hour alike, while a midday sector in the tropics carries more than a dawn sector.
• Precision. The app's notes put the model within about 20 to 30 percent on mid and high latitude routes and about 50 percent near the equator, where the dose is small. The calculator shows plus or minus 30 percent from 30° geomagnetic up and 50 percent below.
• Official status. This is an awareness estimate, not a dosimetric measurement, not an official dose record and not medical advice. For an official figure, ask your operator or use the FAA's CARI-7.

What the numbers mean

• Airline aircrew average about 2.7 mSv a year, with national averages from 1.0 to 3.1 mSv (UNSCEAR 2020/2021, data for 2010 to 2014).
• 1 mSv a year is the public dose limit. It does not apply to crew as a limit; in the EU it is the level above which operators must assess crew exposure (Euratom 2013/59 Art 35).
• 6 mSv a year is where the EU's stricter occupational rules apply, and ARPANSA's reference level for Australian aircrew. ARPANSA says it is not a dose limit.
• 20 mSv is the occupational limit: in any single year under Euratom, and as a 5-year average under the ICRP and the FAA.
• NIOSH sets 85 dB(A) over 8 hours as its recommended exposure limit for a working day. The app shows no band for noise or UV-A, because no occupational limit fits a pilot's year.

The guide How much cosmic radiation do pilots get a year? gives the source of each radiation figure, with per-flight doses published by ARPANSA and the FAA.

• Solar flare radiation on polar flights: aircrew dose and alerts
• Pregnant pilots and cosmic radiation: dose limits and who to ask

Common questions

How much cosmic radiation does a pilot get in a year?

Airline aircrew average about 2.7 mSv a year, with national averages from 1.0 to 3.1 mSv (UNSCEAR 2020/2021, data for 2010 to 2014). Your own figure depends on your hours, cruise level and routes.

How accurate is this radiation calculator?

It gives an awareness estimate. The model is good to about 20 to 30 percent on mid and high latitude routes and about 50 percent near the equator, and it leaves out solar particle events. It is not a dose record or medical advice.

Why do high-latitude routes give a higher dose?

The Earth's magnetic field turns away more cosmic rays near the geomagnetic equator. In the model, an hour at the same level gives 0.35 of the polar dose rate at the geomagnetic equator and the full rate at the geomagnetic pole.

Does the solar cycle change my dose?

Yes. An active Sun keeps more galactic cosmic rays away from the Earth. The model swings the dose by up to 25 percent each way over an 11-year cycle, lowest around 2025 and highest around the end of 2030.

How loud is a cockpit?

In the app's table, about 76 dB(A) at the pilot's ear in airline jets with no headset, 84 in turboprops, 92 in piston aircraft and 95 in helicopters. In an airline jet the radio and intercom keep the level under a headset between 77 and 83.5 dB(A), depending on the headset.

Do pilots get more UV in the cockpit?

UV-A grows with height, about 9 percent per 1,000 metres in the app's model, so at FL370 the same sun carries about 2.6 times its sea-level UV-A. Windshields block most UV-B. How much UV-A reaches you depends on the glass and the sun on each sector.

Can Off Chocks work these out from my logbook?

Yes. Turn on Health insights in Settings and Off Chocks estimates your radiation dose, noise dose and UV-A load over a rolling 12 months from the flights you log, using each route, its times, the aircraft type and your block time. It runs on your device.