> For example, it's easy to find people who get anxious about xrays but not about flying even though it gives you roughly the same amount of exposure.
A 7 hour flight gives you 1/5th (.02 mSv- 2000x daily background exposure) as much as a chest xray and 1/350th as much as a chest CT. They're only similar if you fly relatively often, and if you get any kind of CT you need to fly a LOT to make them comparable.
Your example also under-rates the danger of xrays compared to flying under models that are suspected to be more realistic than current linear threshold. If acute doses are worse than spread out doses, the xray is even worse than the plane.
As a child, you would have gotten even less radiation from a flight. An xray exposes you to roughly the same dose, since the image is confined to a specific spot on your body. Everybody gets the dose delivered to a roughly 1'x1' area, yadda yadda. On a flight, every part of your body receives more radiation- so a 50 lb child will get 1/4th as much radiation as a 200 lb adult. If they get an xray, a smaller area needs to be exposed... but not 1/4 the size. It's actually related to the square-cube law, since the image is cross-sectional but dose delivery depends on volume.
During times of calm space weather, travelers on flights from say, Chicago to Beijing, over the north pole get the equivalent radiation dose of a chest X‐ray (~0.1 mSv) [e.g., Meier et al., 2009; Bennett et al., 2012, 2013; Joyce et al., 2016; Tobiska et al., 2016].
A 7 hour flight gives you 1/5th (.02 mSv- 2000x daily background exposure) as much as a chest xray and 1/350th as much as a chest CT. They're only similar if you fly relatively often, and if you get any kind of CT you need to fly a LOT to make them comparable.
Your example also under-rates the danger of xrays compared to flying under models that are suspected to be more realistic than current linear threshold. If acute doses are worse than spread out doses, the xray is even worse than the plane.
As a child, you would have gotten even less radiation from a flight. An xray exposes you to roughly the same dose, since the image is confined to a specific spot on your body. Everybody gets the dose delivered to a roughly 1'x1' area, yadda yadda. On a flight, every part of your body receives more radiation- so a 50 lb child will get 1/4th as much radiation as a 200 lb adult. If they get an xray, a smaller area needs to be exposed... but not 1/4 the size. It's actually related to the square-cube law, since the image is cross-sectional but dose delivery depends on volume.
https://www.xrayrisk.com/faq.php