(Not my field of expertise but putting it out there)

if reproduction is your only concern you could perhaps bank some sperm? (Or eggs, whatever takes your fancy)

i worry more about the cancer risk myself but then I’m an old fart!

As you say Ian it’s complex....a lot of the modelling, such as the various FAA tools such as “CARI”, look only at cosmic rays and as you rightly say as the Sun becomes more active around Solar Max the cosmic ray count reduces..so in the surface that sounds (and is good thing)

However problem then is that around Solar Max you are at increased risk at getting a real short term spike in radiation from a solar particle event....

Avoid high altitudes at high geo-magnetic latitudes (roughly the Poles, northern Canada) is probably the way to handle it if it is something one is fussed about.

A few studies by the Danes and the Kiwis, back at the turn of the century highlighted the significant increased risks of contracting Leukaemia, specifically Acute Myeloid Leukaemia (AML) for long haul pilots. I fly long haul, and I have a child recovering from AML. Do a search for the following:

Radiation-induced acute myeloid leukaemia and other cancers in commercial jet cockpit crew: a population-based cohort study.

AFAIK, under EASA, airlines have to keep a record of a crew members exposure to radiation. Many do this via the CARI programme integrated into crew rosters. Is it worth asking your admin department? As far as measures to minimise go, I assume it is nearly impossible to reroute to lower latitudes in your airline, leaving flying at lower altitudes as the only method. Personally, I don’t go above FL350 if I can help it above 60N. If that means sticking on an extra tonne or two, so be it.

I think the drive the airport is potentially more hazardous to your ability to produce offspring.


If you’re this concerned go crop dusting....really.






The chemicals will make your sterile.....bugger.






Become a simulator instructor and live like a mushroom in the dark.
Till a King Air has an engine failure and rolls into your building.


Maybe stay at home in bed.

FWIW I used the CARI program many years back to track my exposure - since (as IanW mentioned) the level of Galactic cosmic radiation reaching the upper atmosphere depends upon the Sun''s level of activity (cf. Solar wind) CARI used to use an observed variable called the heliocentric potential (for which you had go online to the likes of NOAA) in it’s algorithms to in part calculate your exposure...that variable at the time was available for I think monthly Intervals. It is possible later versions of CARI will pick that value up automatically once it knows your flight date but I haven't looked at it for a while. Also CARI needs your route and very importantly your flight’s vertical profile. Fundamentally if you want to track your own exposure accurately, rather than come up with generic figures, you need to do a bespoke calculation for your flights, which involves quite a bit of book keeping for every sector regarding date, level changes and route taken and other stuff in order to produce anything really meaningful - simply entering AAA to BBB and a mean flight level can lead to considerable errors.

I did all this this for a year on longhaul and it worked out generally at very roughly 40 micro (uSv) on a Europe -Midwest USA sector and less on other routes.

As for easily avaliable commercial personal dosometers - my contacts tell me there''s nothing really easilly available to the individual as a single device that will cover the full "spectrum" of radiation we are exposed to with adequate sensitivity across the range of radiation types...but I know some disagree.

(Edit to add: For info found my records. Year was 2000, so around a Solar Maximum, aircraft 744 so assume start cruise low with FL’s low 300s end up high FL 300s

typical approximate doses calculated by CARI :

Typical highest “dose” sector Europe -Japan, 50ish uSv
Europe-West Coast States high 40 uSv
Europe-eastern Seaboard 30 uSv
Europe -Central Africa 20 uSv
Europe -South America 30 uSv

It’s a fraught subject. Some Captains are keen to stay low, certainly below 400+ for that reason. I used to routinely fly up to 470/490 on biz jets. 490 was the artificial ceiling imposed by the operator as at 490 or below the EASA record keeping for exposure is essentially a book keeping operation based on time flown whereas above 490 specific individual monitoring was required. I don’t know the exact details, but I can confirm that I have (currently - touch wood) healthy children despite both mid-latitude high altitude stuff and long haul northern canada/Russia.

Od course, the plural of anecdote ain’t data, you pays your money &c.

Thanks for posting that..as much as anything because it prompted me to get my m’sand my u’s sorted out in my earlier post :\

I was typically picking up about 220 uSv a month , mixture of routes, when I did my logging, flying about 65-70 hours a month (those were the days).

If the high altitudes still bug people it is worth running dummy sectors with the same profiles, e.g. east/west high latitude vs. North south through the likes of CARI to see where the problems really lie and why “capping” levels down near the equator is almost pointless....