System of Fear: A Dose of Radiation Reality

14 10 2013

In line with last week’s post, please see the below infographic, which paints radiation doses in the visual context of a sort of system of planets according to size (click to enlarge):

SystemofFearI

As is plainly evident, it’s shocking how much the public perception of radiation doses and negative health effects differs from reality.

(For example, in today’s perceptual climate, who would believe that a person could live within a mile of a nuclear powerplant for a thousand years before receiving the radiation dose from a single medical CT scan?)

If feedback to this is positive, I think I’ll make this the first in a series of similar infographics.  (Perhaps people would find it interesting/useful to next have illustrated the relative magnitudes of nuclear disasters?)

_______________________________________________

If anyone doubts the numbers in the above diagram, please feel free to investigate the references for yourselves!

International Atomic Energy Agency:

http://www.iaea.org/Publications/Factsheets/English/radlife.html

U.S. Environmental Protection Agency:

http://www.epa.gov/radiation/understand/perspective.html

U.S. Nuclear Regulatory Commission:

http://www.nrc.gov/about-nrc/radiation/around-us/doses-daily-lives.html

U.S. National Council on Radiological Protection (via the Health Physics Society):

http://hps.org/documents/environmental_radiation_fact_sheet.pdf

U.S. Department of Energy:

http://lowdose.energy.gov/faqs.aspx#05





Nuclear and Atomic Radiation Concepts Pictographically Demystified

10 10 2013

Greetings, all.  Today I’m attempting a different, largely pictographic approach to demystifying the concept of “radiation” for the layperson.

Despite the hype, radiation is a natural part of our planet’s, solar system’s, and galaxy’s environment, and one that our biology is equipped to mitigate at ordinary intensities.  It’s all actually surprisingly straightforward.

So, without further ado, here goes – a post in two parts…

PART I – Radiation and Radioactivity Explained in 60 Seconds:

The Atom

This is a generic diagram of the atom, which in various combinations of the same bits and parts is the basic unique building block of all matter in the universe:

Atom_Labels

This somewhat simplified view of an atom is what makes up the classic “atomic” symbol that most of us were exposed to at the very least in high school.

Radioactive Atoms

However, what is almost never explained in school is that each atomic element comes in different versions – slimmer ones and fatter ones.  When an atom’s core gets too large, either naturally or artificially, it starts to radiate bits of itself away in order to “slim down.”  This is called being radio-active.

So, there’s nothing to “radiation” that we all haven’t been introduced to in school.  Radiation is the name given to familiar bits of atoms (electrons, protons, neutrons) or beams of light when they’re being flung away by an element trying desperately to squeeze into last year’s jeans… metaphorically-speaking, of course.

Here is a diagram illustrating this process.  (Relax! – this is the most complicated-looking diagram in this post):

RadioactiveAtom_Radiation_Labels

So, when a radioactive element has radiated enough of itself away and is no longer too large, it is no longer radioactive.  (We say it has “decayed.”)

That’s it!

That’s as complicated as the essential principles of radiation and radioactivity get.  It’s just basic chemistry that isn’t covered in high school, (though in my opinion it should be!).

PART II – Take-Home Radiation Infographics

So, in an effort to help arm you against the rampant misinformation out there, here is a collection of simple diagrams explaining what everyone out there seems to get wrong.  (Feel free to promote and/or distribute with attribution!)

First, what’s the deal with “atomic” energy/radiation versus “nuclear” energy/radiation?  Do they mean the same thing?  Do they not?  Here’s the skinny:

AtomicvsNuclear_labels

That’s all.  “Nuclear” means you’ve zeroed in on an atom’s core, whereas “atomic” means you’re talking about something dealing with whole atoms.  No big mystery there.

Next, here is a simple diagram explaining the three terms used to describe radiation that are commonly misused in the media, presented clearly (click to enlarge):

MisusedTerms_labels

(Armed with this, you should be able to see why saying something like, “The radiation is releasing contamination!” doesn’t make a lick of sense.)

Now, here is a diagram explaining the natural sources of radiation we’re exposed to everyday on planet Earth:

RadiationNaturalSources_labels

And here are the basic principles of radiation safety, all on one, clean diagram (click to enlarge):

RadiationSafetyv2_labels

The End! 

Despite the time and effort spent socially (politically?) promoting an obscured view of this science (or so it seems), there is nothing more mysterious about radiation than what you see here.

Please feel free to contact me with any questions, and remember:  We have nothing to fear but fear itself!

Semper Exploro!





Radiation, Japan, and irresponsible reporting: Part III

19 04 2011

Image of one of the damaged Fukushima reactors. (Credit: Reuters)

As detailed in Part I and Part II of this series, the vocabulary of radiation science, (known as “health physics,”) is being chronically misused and confused by the news media in its coverage of the Fukushima nuclear incident in Japan, and critical context is being ignored when details are reported.  The result?  There is so much misinformation flying around that it’s basically impossible for an ordinary person to make sense of the situation.

This post series is an attempt to help.  So, to briefly recap:

  • “Radiation” cannot travel in a cloud, nor can it “settle” onto something.  Radiation is simply the atomic/sub-atomic particles and rays of x-ray-like energy beamed out from overweight, (i.e. radioactive,) elements.  The effects of these particles/rays are pretty short-range.
  • “Radioactive material” is what can do the distance traveling – actual bits or chunks of stuff – which itself emits radiation.
  • When some radioactive material lands somewhere you don’t want it, it is called “contamination,” and none of it is really mysterious.  You can wash contamination off, wipe it up, etc.  It’s really just chemistry, after all.

Let’s take a moment to further the discussion and talk about why radiation is something we don’t like, and what we can do about it.  In truth, radiation is far more natural than anyone (particularly with an anti-nuclear agenda) tends to broadcast.

Water around Idaho National Laboratory Advanted Test Reactor glows blue due to the intense radiation field. (Credit: Matt Howard)

To be completely fair, you should understand that light is radiation – that’s right, regular ol’ light from your edison bulb.  However, it’s low enough energy that it doesn’t do any damage to you.  All types of light are types of radiation, including infrared light, ultraviolet light (which is why it burns/causes cancer), microwaves (which is why it can cook your food), x-rays (which is why you need a lead apron as a shield at the hospital), as well as the stronger gamma-rays that are one of the main types of radiation people talk about when they say something is radioactive.

However, what few know is that your own body emits gamma rays.  It’s a fact (see: potassium-40).  So do plants growing in the wild, the sun above us, generally half of the mountains around you, and your granite countertops.  Our bodies are built to withstand ordinary amounts of radiation exposure.  Alpha and beta particles (other types of radiation) can’t even penetrate our skin.

Radiation is a normal part of the natural world.

Giant fireballs rise from a burning oil refinery in Ichihara, Chiba Prefecture. (Credit: Associated Press)

So, now that we understand that, of course there are intensities of radiation that are unhealthy, just as breathing too many chemical fumes can be quite harmful to you, (e.g., gasoline, cleansers under your sink, bleach, etc.)   This is one of the largest misconceptions about the Fukushima disaster – that it is the worst part of the earthquake/tsunami effects.  In my opinion it is not.

The nuclear reactors are definitely gaining the most media attention, but the biochemical aspects of the earthquake/tsunami disaster are much more widespread.  -Ruptured sewer lines across the nation.  -Burning oil refineries.  -Dumped chemical warehouses swept over by the giant wave and spread out all over the place.  -Biological hazards.  The media is ignoring the true scale of the disaster in its addiction to the nuclear mystique.

But I digress.  Yes, there certainly are harmful and dangerous levels of radiation being emitted by the damaged reactors, which like a more powerful version of a sunburn can damage DNA and cause certain types of cell mutations (cancers).  So, we ask the question: If you’re near to a source of harmful radiation, whether it’s a nuclear fuel rod or a cloud of fallout, what can you do about it?  Fortunately, the answer is very simple.  There are three things you can and should do, and these are the same things you would do in the event of a nuclear attack as well, (so take heed):

  • Get away from the source as fast as possible.  [Time]
  • Get as far away from the source as you can.  [Distance]
  • Position yourself so that dense objects are between you and the radiation source, such as hills, mountains, brick walls, mounds of dirt, etc.  [Shielding]

That’s really all you need to keep in mind, and in that order.  Time, distance, and shielding.  The intensity of radiation drops off exponentially the farther away from it you get, and the less time you spend being bombarded by radiation, the more likely your natural defense mechanisms will be capable of dealing with it and you won’t even notice.  If you can’t do the other two, then maximize your shielding and ride it out.

So, this has swelled beyond my original intent, so we’ll leave explaining the utility of iodine pills ’till next time.  But trust me.  -If you’re not in Fukushima Prefecture, you don’t need them.  (And even then, you probably still don’t.)

One final note of context.  Neither Chernobyl nor Three Mile Island (which was  nothing like Chernobyl) were a result of natural disasters.  Peculiar engineering and human error were the culprits there, respectively.

The Fukushima plant, on the other hand, took a cataclysmic magnitude 9 earthquake followed by an apocalyptic 25-foot-tall wall of water.

I think it’s a testament to their superb engineering that the reactors there are even standing at all.





Radiation, Japan, and irresponsible reporting: Part II

22 03 2011

Example of a uranium ore mine, a very natural source of radiation and radioactive material… and contamination if you track uranium dust home with you. (Uncredited)

So, after my last post, you’ve got the subtle (and not-so-subtle) differences between radioactivity (overweight atoms), radioactive material (the material containing or composed of the overweight atoms), radiation (invisible light and particles emitted by the overweight atoms), and contamination (having radioactive material someplace you don’t want it).

Hopefully, you can also see why mixing these up prevents people from making any sense of either the situation at hand or what scientists tell them (when they’re actually interviewed) on the news.

For instance, if a newscaster says something akin to, “A plume of radiation was released,” well, that doesn’t really make sense.  That’s like saying, “A plume of blue has been released.”  You can release a plume of blue something, be it smoke, confetti, etc., but you can’t release blue.

Similarly, radiation is produced by something else – so, you could say, “A plume of radioactive steam has been released,” and that means that the plume of radioactive steam would be producing radiation as it moved and dissipated, which is perfectly reasonable.  However, just saying the radiation part is nonsensical, and further, adds to the terrifying mystique around the word “radiation” …

Radioactivity is just chemistry and physics, nothing more, nothing less.

Let me provide a second example.  If a scientist reports that there is “radiation” detected somewhere, you now are prepared to understand what he’s not saying, which can actually be more valuable than what he said.  In saying that radiation has been detected, the scientist has not said that they’ve actually found the radioactive material responsible for producing the radiation, or further, any radioactive contamination.  He’s simply saying that instruments have detected either the invisible, high-energy light (gamma rays/x-rays) or atomic particles being shed by radioactive material.  The radiation in this case could be from the sun, plants, humans (yes! – we’ll get to that), granite, radon from igneous rocks, or something more sinister – the scientist hasn’t specified.  He’s reporting facts.  -At such and such a location, radiation of a given intensity has been found.

So, what can such a statement tell you?  It can tell you from a health perspective how long it’s safe to be in the area where the radiation was detected, but it says nothing about the nature, presence, or movement of the material responsible for producing the radiation.  I cannot stress how important it is that this be made clear in the media.

So, for retention’s sake, I’ll pause here to keep these posts divided into brief segments.  Stay tuned for Part 3, where we discuss how radiation is truly crippled by the laws of physics, how that can be best (and simply!) used to your advantage, and just exactly why it’s bonkers for everyone to be snapping up iodine pills.

Until then, cheers.





Tales from a nuclear rocket station

21 02 2011

One of the great pleasures of my research into the ’60s development of nuclear rockets for space exploration are moments like the following, which I pieced together from archival records and oral history…  (If I find enough of these to write, I might collect them into a book sometime.  Feedback welcome.)

Moonrise over the Nevada desert.

Richard Nutley, a supply manager for the joint NASA-Atomic Energy Commission Nuclear Rocket Development Station (NRDS), stood with an infuriated NASA accountant next to the partially-constructed Engine Test Stand One.  The year is 1961.

The test stand was a maze of pipes connecting two giant, white, spherical hydrogen reservoirs to a towering concrete-and-steel gantry.  It appeared much like a lone launch pad in the middle of the sage-covered desert valley where the nation’s most advanced propulsion system was being developed and tested.  A network of rail lines crisscrossed the flats, connecting the test stand to several other structures where nuclear rocket reactors were assembled and prepared.

Together, the NRDS represented the nation’s attempts to build a rocket powerful enough to take bases to the Moon and astronauts to Mars, and they were meeting with great success.

Richard grinned, trying not to laugh as the accountant, who’d arrived from NASA headquarters in Washington D.C. that morning, dusted off his suit and attempted to empty gravel from his Italian leather shoes.  A mighty dust devil had swept across the construction site without warning, catching the accountant completely unprepared.  Already in a sour mood from the unexpected hour-and-a-half drive from Las Vegas to the Nevada Test Site earlier that morning, the whirlwind was the last straw.

Richard shook his head.  Anyone who’d bothered to look into the NRDS knew better than to wear nice clothes to the site.

Walking back toward the car parked at the fence-line to the test stand and stifling back laughter, Richard looked up to see that the moon had risen over Vegas, and it loomed on the horizon.  “That’s where we’re going with this thing,” he said.

“Where?” the accountant replied, annoyed.  “What are you talking about?”

“The moon,” Richard said flatly.

The NASA accountant looked at Richard and said, “You would never see the moon in the daylight back East.”

Richard drove the NASA accountant back to Vegas and never saw him again.





Yanks and Brits join forces to design private interstellar spacecraft

7 01 2011

Rendering of the Project Daedalus interstellar probe, the grandfather of Project Icarus. (Credit: Adrian Mann)

That whole American Revolution thing is water under the bridge for two forward-looking spacefaring organizations.  In a joint venture between the Tau Zero Foundation, a private American advanced space propulsion charity, and the British Interplanetary Society, a spacecraft known as Project Icarus has taken shape.

So, what exactly is Project Icarus?  To put it simply, Icarus is an outgrowth of the 1973-1978 interstellar mission study spearheaded by the British Interplanetary Society called Project Daedalus.  In Daedalus, details of how to achieve a flyby mission to nearby Barnard’s Star were worked out, leading to the proposal of a massive, two-stage, nuclear-fusion-propelled spacecraft (see image above).  As designed, Daedalus would cover the six-light-year (36 trillion miles) distance between us and Barnard’s Star in only 50 years(!).

Icarus aims to achieve generally the same goals but with one important difference – Icarus will use technology available today, similar to the US Navy’s Project Longshot in the late 1980s.  Check the Icarus Project out if you get a chance, and should you feel philanthropic, offer them some support.

It’s initiatives like these that can produce the breakthrough technologies we need to get interstellar exploration off the ground.





Space radiation has Astronauts seeing stars

2 01 2011

View of Earth at night from the International Space Station. The thin atmosphere layer visible acts as a natural radiation shield. (Credit: NASA)

There are many astronauts experiences that are well understood.

Everyone knows about “weightlessness,” or floating in a microgravity environment, (which is actually perpetual free-fall around the Earth, but that’s a technicality for another post.)

Everyone has heard about the problem of space sickness that hits some astronauts and not others.   Disruptions in our sense of orientation (i.e., up and down,) are likely to blame.

However, what many do not know about are the strange “flashes” of light astronauts see while in space and what it might mean for their future heath.  With commercial space travel on the horizon and space tourists and commercial astronauts lining up to take part, the realities of space travel must be explored and disclosed.

The Earth’s atmosphere normally acts as a shielding layer, protecting the surface from cosmic and solar radiation.  However, when we travel beyond the atmosphere, (i.e., space,) we increase our exposure to such radiation.  In truth, these “flashes” reported by astronauts are actually electrochemical reactions occurring in astronauts’ eyes as a result of high-energy radiation striking their retinas.  A radiated particle passes through the lens of the eye, strikes the retina, and fakes out the optic nerve, which in turn interprets the signal as light.

So, aside from being strange, what are the potential effects of these flashes?

There appears to be a relationship between this radiation exposure and later development of cataracts, a disease characterized by a clouding of the lens of the eye.  According to a 2001 study, a total of 39 astronauts have developed cataracts later in life, and 36 of them flew on high-radiation missions, such as those to the Moon.

Scientists are currently working on nailing down the genetic link between radiation exposure and cataracts, but until then, it simply appears that exposure to space radiation increases your risk of cataracts later in life.  Advances in and the regularity of surgically-implanted interocular lenses make cataracts less of a concern, but effects like these are something for the aspiring casual spaceflight participant as well as for future planetary and deep space explorers to be aware of.








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