When we travel to nuclear facilities in foreign countries, we tend to bring alarming realtime dosimeters whose job is to start beeping loudly if the radiation dose rate in a given location is above safe limits. They also keep track of the total absorbed dose since they were last reset. Just so you know, mine has never beeped.

So, how much radiation am I exposed to when I visit places like BN-350?

On my recent trip to Kazakhstan, in three days within the contaminated areas of the reactor facility, I accumulated a 12 microsievert dose equivalent from gammas and < 1 microsievert from neutrons. Now for people who do not work with radioactive material on a regular basis, that's probably clear as mud. So to give you a good comparison and sense of scale, I left my realtime dosimeter on while I flew back home. On my 11.5 hour flight from Frankfurt to Atlanta, I accumulated 259 microsieverts from neutrons and 18 microsieverts from gammas.

Interestingly, sending the dosimeter through the x-ray machine didn't accumulate any dose at all, so whatever the detecting medium is in there (anyone know? this is an N2 model), it must have a low-energy cutoff of above 100keV or so.

Anyway, the moral of this story is that working in decrepit Soviet breeder reactors is can be very radiologically safe, though I wouldn't recommend you try this on your next vacation trip to Aktau. Flying, on the other hand—you're getting cooked up there! Do you smell bacon?

[In case you are unaware, the Earth is constantly bombarded by high-energy particles from SPACE aka cosmic rays. These rays interact with atoms in the atmosphere, destroying them, and causing showers of random nuclei. This stuff is happening all the time, all around us. You just can't see it because you need glasses they're very very small. The byproducts of these reactions are mostly absorbed high in the atmosphere, though some of the higher-energy stuff does make it down to the surface of the Earth, wreaking havoc on modern integrated circuits, etc. The higher up in the atmosphere you go, the less shielding it provides against these high energy particles and their only-slightly-less-high energy reaction products. Thus, when you fly in a plane, you're being pelted with RAYS. And occasionally BEAMS.]