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





A Radioactive Astronaut-Hopeful (Space update)

20 11 2010

Me probing an old military well in the Nevada wilderness for geologic data.

By education and trade, I’m a geologist, having worked now in the professional world for more than six years getting my boots dirty performing hydrogeology, water resources, drilling, geomorphology research, and environmental contaminant transport and remediation work in some of the most remote territory this country has to offer.  However, in my push toward becoming an astronaut, one may wonder why I suddenly think it’s a good idea to be working as a radiological engineer and pursuing graduate work in Radiation Health Physics (in addition to my Space Studies work at UND).

Why not study something more direct, like Planetary Geology (Astrogeology)?

The answer, while seemingly obscure, is simple:  What does geology, outer space, the Moon’s surface, Mars’s surface, and advanced spacecraft power and propulsion systems all have in common?  Radioactivity.

Boltwoodite and Torbernite, uranium-bearing mineral samples. (Credit: Ben McGee)

On Earth, (and other heavy rocky bodies,) radioactivity is a natural occurrence.  Plants (and even human beings) all beam out radioactive gamma rays from a natural isotope of Potassium.  (This is prevalent enough that you can calibrate your instruments to it in the wild.)  Even more to the point, radioactive Uranium and Thorium are more common in the Earth’s crust than Gold or Silver.  These elements are crucial to determining the ages of rocks.

Now, go farther.  As we move outside the Earth’s protective magnetic field, (i.e., orbit, Moon, Mars, and everything beyond and in-betwixt,) cosmic and solar radiation are essentially the greatest hazards an astronaut may face.  Radiation shielding and measurement are of primary importance.

Illustration of a manned NTR exploration spacecraft and landing capsule in Mars orbit. (Credit: Douglas/Time Magazine, 1963)

Farther still, once a spacecraft travels beyond about Mars, the intensity of sunlight is such that solar panels are inadequate to supply necessary power.  Nuclear reactors, (Radioisotope-Thermoelectric Generators, or RTGs,) are necessary.

Plus, in order to get out that far (to Mars or beyond) in a reasonable amount of time, our chemical rockets won’t provide enough kick.  Instead, Nuclear Thermal Rockets (NTRs) are about the most efficient way to go, something I’m in the midst of researching in earnest.

Hence, in addition to having experience as a field geologist (for future visits to the Moon, Mars, asteroids, etc.,) being trained to swing a radiation detector around, understanding the exact hazards radiation poses and how it works, and knowing your way around a nuclear reactor are all uniquely suited to space exploration.

Admittedly, it’s an unconventional path, but it’s my path: Riding gamma rays to the stars.





Suiting up for radiation

7 09 2010

Common radiation detection instruments. (Credit: Nevada Technical Associates, Inc.)

So, I’m heading out this week for radiological instrumentation training.  And while I’m studying the latest in handheld “duck-and-cover” devices, I thought I’d take a second to talk about radiation protection.

Actually, everyone is used to doing it.  The dental chair.  The strangely-shaped things in your mouth.  The lead apron.  -Or how about gooping up before hitting the beach or the hotel pool?  X-Ray Machines and UV rays.  -Not quite scary as they are inconvenient.

Well, what are x-rays and ultraviolet rays other than electromagnetic radiation?  -That’s right, they’re the same as the “radiation” that serves as the terror-inducing, little-understood plot point in a zillion bad sci-fi flicks.  X-rays are simply a stronger variant of the ultraviolet-rays that can fry your skin and a weaker variant of the gamma-rays that beam out of radioactive cesium and can fry your DNA.

The apron you wear at the dentist and the sunblock you slather on are common radiation shields.  And, for that matter, so is your skin.

Radiation is a way of life – it beams down from the sun and up from the Earth’s rocks.  Plants soak up naturally-radioactive potassium and beam radiation at you from all sides, 24-hours-a-day.  We’re built to handle it down here.  Life has adapted.  -And while politicians count on the scary sci-fi-effect the word “RADIATION” has on people, it’s nothing to worry about compared to the chemicals we deal with and transport in day-to-day life.  (Try breathing chlorine bleach for more than a couple of seconds and you’ll see what I mean.  But seriously, don’t do that.)

1999 solar eclipse, highlighting the sun's corona. (Credit: Luc Viatour)

In space, however, it’s a different story.  Without the Earth’s atmosphere to act as a natural shield, we’re unprotected from the sun and distant stars’ powerful cosmic radiation.

To make matters worse, most radiation shields (e.g., lead,) are heavy.  The cost of launching heavy materials up to space is enormous, not to mention that lead is a toxic metal, poisonous to astronauts with long exposure times.

It’s times like these that companies like Radiation Shield Technologies catch my eye.  While they’re not necessarily working on NASA-spirited technologies, (they’re more looking at the emergency responders,) the product they’re offering definitely has out-of-this-world merit.

Namely, they’ve developed a fabric called Demron, which according to a Lawrence Livermore National Laboratory study possesses many of the radiation-shielding properties of lead while being lightweight, flexible, and potentially layer-able with a bullet-proof fabric like Kevlar.

To me, products like this are where we need to start looking to develop the practical tools of next-generation astronauts and space workers (astrowrights).  While Demron currently doesn’t shield well against the most extreme high-energy rays and particles, it is definitely a start, and it’s much more user-friendly and cost-effective (lighter) than lead.

Considering what an effective combination Demron would be with the micrometeorite protection that a ballistic fabric like Kevlar would offer, I would challenge clothing designers to start putting their heads together to incorporate them into comfortable, practical space-wear for our men and women in orbit.

Like on Earth, radiation is a way of life in space, too.  We should start thinking that way, and Demron seems a good place to start.





Confronting radiation fears through symbology

14 06 2010

Traditional Radiation Trefoil Hazard Symbol.

Just a quick note today on radiation and the irrational fear it provokes.  -Take it from someone who works around “rad” professionally in nature and in industry: Radiation isn’t scary.  It’s normal.

Radiation comes from the sun above, the mountains around, the soil beneath, our wi-fi routers, radio stations, and heck – our own bodies emit infrared and gamma radiation, just like radioactive waste.  (Though, granted, at a much lower intensity.)

Micro-waves are, literally, radiation. Yes, you "nuke" your food in a microwave oven, (though there's no danger of making the food radioactive itself.) Microwave radiation is harmful, which is why all microwave ovens are discreetly engineered as "Faraday Cages" - the same protective housings that the military uses to protect sensitive electronics from nuclear blasts.

While some radioactive elements emit particles as well as “energy,” the simple truth is that the same electromagnetic waves that stimulate our retinas (visible light) are identical in form to the elctromagnetic waves that warm our hands in gloves (infrared rays,) cook our food (microwaves,) burn our skin (ultraviolet waves,) check our bones (x-rays,) and that on the extreme end can be very physically harmful to our tissue (gamma-rays and cosmic rays).  Think of them as colors our eyes can’t see.

That’s it.  That’s all there is to it.  Radiation is natural, not just man-made.  We grew up around it, and our bodies are built to take it.  There’s even a fair amount of serious research to suggest moderate exposure to radiation helps keep us healthy by stimulating our defense systems.

So, why the mystique?  Tradition.  Radiation is associated with atomic bombs, nuclear holocaust, physics perceived to be too complex for any ordianry person to understand (which is completely untrue,) and it’s invisible to human senses.  General misunderstanding is the culprit when we really have nothing to fear but… yes, fear itself.

Radio waves are radiation, too, (even though the waves are generally too large to cause harm to our bodies.)

Now – this fear is really getting in the way of some important developments in power, propulsion, and industry.  What can we do to counter such pervasive fear?  Perhaps we should call it like it is.

See the included examples of microwave, radio, etc., radiation symbols that accurately place radiation with radiation.  Enough with the marketing – call an apple an apple. 

Perhaps if we started putting these symbols out with our appliances and various gadgets and at beaches to denote the threat of sunburns and skin-cancer, we’d realize that not all radiation is truly harmful, and that the radiation that is a hazard is something we’re more than capable of dealing with – and that we really already do.  After all, what is sunscreen but a mild, high-density radiation shield?  (Ever wonder why sunscreen is so thick?)

Two cents.

Perhaps something like this out at pool decks and beaches would stress the need for sunscreen? It's compeltely scientifically and technically accurate, too...








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