No, there’s no humor in this thing — just good, solid information.
XKCD put together a chart that shows in geometric terms how various radiation doses work. With a tip of the pen to Bob Parks, the chart notes that cell phones don’t count here because cell phones don’t put out ionizing radiation, the type that causes cancer, but just radio waves.
The chart won’t be easy to read here — click on the image and go to the XKCD site for a bigger, more readable image:
It’s a good, clear graphic in its full size. Go see.