But both help make it clear what you’re looking at when it comes to radiation exposure, in an at least reasonably approachable way for the layman:

XKCD Chart

A Layman’s Intro to Radiation

I recommend you look at both. At least one, if not both, is likely to help clarify things considerably. The former is graphical, the latter is more textual with a few graphs. Which one appeals better depends on how your mind works.

Another place that debunks the idea that all radiation is bad is Grand Central Station:

…the [radioactive] emissions from the granite which Grand Central Station is built from, for example, exceed the permissible Nuclear Regulatory Commission limit for [the nuclear] industry. Grand Central Station couldn’t get a license as a nuclear plant.

Rather clearly — if you wanted to prove radiation dangerous, you could clearly do a health study of people who worked for years in GCS. If radiation were really that bad, then there would be a cancer cluster around the workers there.

However, like Colorado, there is actually a LOWER incidence of cancer among those workers — sufficient to strongly suggest that some exposure is good for you.

Certainly, if the numbers were reversed, you’d never hear the end of the caterwauls about radiation causing cancer.

Despite this rather blatantly self-evident ability to read, I recall getting an “F” in reading at least one term.

Mainly because I refused to read the insipid, uninteresting GARBAGE they tried to force us to read.

They failed with me in their attempts to make me hate reading, and failed utterly.

They don’t fail with most kids, though…

Quantitative reasoning probably does not come naturally to practically anybody; it has to be taught and constantly reinforced.

Actually, sir, I wholeheartedly disagree. We are all the survivors of people who reasoned quantitatively and correctly. Just as with love of learning and reading, though, our schools have taken it upon themselves to turn the populace into drooling idiots who tremble with fear at the idea of math, reading, or critical thinking.

The goal of schools is not to teach kids to do any of these things, it is anathema to that. To make a sheep, you must teach dull, unthinking obedience to authority, and math, reading, and critical thinking are all negative influences towards that goal.

Hence most people are “taught to read” by giving them “old classics” and other suitably boring and insipid things that, instead of making reading enjoyable, make it painful. So many adults stop reading once they get out of high school or college and never pick up books voluntarily again. They associate reading with pain, not pleasure.

Likewise, math — the modern teacher makes people confused about how to think about math by either teaching rote memorization (anathema to the human mental process) or by attempting to do some stupid fixed-path-to-understanding, when each person needs to find their own routing paths for how to think about its concepts effectively. Math becomes associated with pain and humiliation and difficulty… so people never want to do anything with it again once they get out of school. They’ll happily accept the numbers someone else gives them, without really thinking much… because if they actually spotted something wrong, well, hey, they might have to do some math themselves.

Human minds are BUILT for abstract reasoning. It’s one of the things that differentiates us from all other animals — we are able to deal with “meta” on a vastly higher level of complexity than any other creature on earth — the typical 5yo has more inherent understanding of mathematics than the best-trained, full-grown chimp on the planet.

It takes 12 years of serious schooling to beat the desire to think out of people.

“Did anybody here ever heard about radiation hormesis? That is, about healthy effects of low-dose radiation?”

It has been demonstrated many times in studies using rodents that low level exposures (2 to 4 times background) prolong lifespan. But, as far as I am aware no one has come up with a verifiable model for why this should be so.

It is worth noting that there are several areas in the world where there are concentrations of U and Th in surface rocks & solid that create background levels 10+ times higher than most other areas. I forget exactly where these areas are, but they are in Brazil, west Africa, and India. The residents of these areas do not have higher incidents of birth defects or cancer rates compared to similar populations which live in areas of more ‘normal’ background radiation.