I noticed that at ground level, the dose rate was 1 or 2 uSv/hr, but after take off it dropped!!! From 1000 feet (eyeballed) to about 5,000 feet it read 0 uSv/hr on the Poli (1 or 2 CPS, max!). This was due to being too far from the ground radiation (NORM), but too low to pick up lots of background cosmic rays.
My Polimaster misses most cosmic rays and mostly picks up mostly uranium, thorium, potassium, and bremsstrahlung radiation. Neat!
By the time I hit about 15,000 feet the dose rate was rising again. By 33,000 feet the dose rate was at its peak of about 0.5 uSv/hr. I know from the spectrum that most of my dose was from high energy particles. This means my Poli misses most of this dose. lol
Ironically, the plane was probably the source of most of my low level energy dose due to high energy particles striking the hull.
As for the x-ray machine, what could I do? I told the TSA guy what the detector was and he just stared at me… so oh well lol