A Physicist Grumbles About Jericho

As regular readers know, I’ve been watching the CBS show “Jericho,” about the town of Jericho, Kansas and what happens after Denver vanishes in a nuclear conflagration. The drama has been so-so, but in the pilot I was hooked by the eerie and frightening sight of the mushroom cloud rising into the air.

So, into the second episode. We’re ticking along, the fine upstanding citizens of Jericho merrily worrying about the fallout that’s headed their way. Someone says that Denver was probably hit with a hydrogen bomb. “How are they different from nuclear bombs?” someone else asks. And the mysterious-stranger-with-a-secret ominously says, “They literally explode the air.”

He probably said something after that, but I couldn’t hear it over my choked-back cries of rage.

So: a short primer on nuclear weapons. I’m a physicist, so you know I’m right.

Fusion and Fission Weapons

Nuclear weapons fiddle with atoms’ nuclei to release a whomping huge amount of energy. They come in two flavors, depending on whether they use fission or fusion.

Fission bombs were the first kind created. When people talk about atomic bombs, this is usually what they mean. The idea is that you take an atom and, using neutrons, split it into smaller bits, plus neutrons and some leftover energy. If you get enough of the right kind of material smushed together, those extra neutrons from one atom splitting causes other atoms to split, and so on and so on. The result is a cascade of splitting atoms and a huge amount of energy released in a split-second. In other words: big boom. To smush the radioactive material together, you can shoot a bullet of the material into a target made of the same material, or you can surround a core of the material with normal explosives and squeeze it down like play-doh in your fist. Dangerous play-doh.

Fission bombs are okay, and they’re dead easy to make if you’ve got the right uranium or plutonium hanging about, but you run into a couple of problems with them. One, they can explode too early, before you’ve smushed all of your material into a compact-enough mass to make the fission reaction run away. Then you get a small boom and a lot of left-over radioactive material that gets spread around. Hello, dirty bomb! Two, at best you get an explosion that’s equivalent to around 700 to 750 kilotons (kt) of dynamite, because you can only use up so much of your radioactive fuel before it all goes kablooey. 750 kt is a lot, but you’ll want something bigger when your next-door neighbor drives up in his shiny new weapon of mass destruction.

Enter the fusion bomb. Instead of splitting atoms’ nuclei apart, fusion bombs smush nuclei together. You start with something like hydrogen (or, really, a version of it called tritium) and squeeze it together until you have helium and a whole bunch of energy. The hydrogen bit is why they’re sometimes called “hydrogen bombs.” In theory you could squeeze the tritium together with regular explosives. In practice, you do it with a separate fission bomb. Fusion bombs are really effective, using almost all of their nuclear fuel, so you can build bombs that are small enough to be delivered by rocket or whatever but still pack one hell of a wallop. How big? Megatons (Mt). The USSR detonated the world’s largest fusion bomb in 1961. It had a yield of 50 Mt.

Both fission and fusion bombs are nuclear bombs. And, he says, finally getting to the punchline, they do not literally explode the air. I mean, c’mon. The real difference is that hydrogen bombs are much more powerful and efficient.

(ETA: phanatic pointed out that, in effect, nuclear weapons do explode the air. The overpressure and shock wave aren’t caused by the bomb’s plasma ball, like I had thought, but by the gamma rays ionizing the air and causing ozone and other smog-like products, which is then heated by the bomb’s x-rays. The effect is common to both fusion and fission weapons. My only defense is that, as I say in the next paragraph, I thought they were referring to the concern that nuclear bombs would ignite the atmosphere.)

The only thing I can figure is that the writers remembered that the Manhattan Project scientists were afraid that a nuclear explosion would ignite the atmosphere. It doesn’t happen. Atmospheric nitrogen requires much higher temperatures to fuse than you get in the center of the nuclear fireball, which cools surprisingly quickly because the fireball is expanding so fast.

So, to sum up: hydrogen bombs are different because they’re super-powerful, requiring a fission bomb to set them off. They do not literally explode the air. While they sort-of explode the air, so do regular fission weapons.

Hey, that was kind of fun. While I’m on a roll, let’s discuss fallout!

Fallout

In the same episode, everyone’s afraid of the fallout coming from Denver. Run! Hide! Put plastic sheeting over your windows and doors to keep it out and you’ll be okay!

Er, no. Not even close. Here’s the thing: fallout is radioactive. When a nuclear bomb cranks up, it makes all kinds of nasty radioactive byproducts. Many of them tend to be unstable, which is both good and bad. Good: they decay rapidly. Bad: in decaying, they toss off beta and gamma radiation the way college students toss down tequila. All of that plastic sheeting will keep out the fallout particles themselves. The radiation that the particles are emitting? Ha ha, he laughs hollowly.

What you want is as much mass between you and the particles as possible. More mass means more radiation is absorbed by the stuff between you and the fallout and less is absorbed by you directly. The beta radiation isn’t so bad. It’s the gamma rays that’ll get you. They penetrate like crazy. Your best bet is to put a lot of earth between you and the fallout, so your basement is better than your attic. Just over three and a half inches of dirt will cut the gamma radiation flux in half. A reasonable rule of thumb is that you want five to ten times that thickness to give you really good protection, so you’re looking at one and a half feet to three feet of dirt for really good protection. If you’re lucky enough to use concrete instead, you can get by with one to two feet.

What about air? you ask. Won’t it bring in the nasty fallout particles? Yes, but most of the really dangerous stuff has the consistency of sand, so it’s not too hard to filter out.

But do not sit near your house’s entrance and listen to the probably-radioactive rain pattering down.

That’s enough for now. I’ll probably have more grumbles later, like people who think that drinking iodine is a good substitute for potassium iodide pills, and saying that storms travel from Denver to wherever Jericho is supposed to be in Kansas in two hours. What, they have 100-mile-an-hour winds to blow the storms the 200 miles from Denver to the Colorado-Kansas border?

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36 Comments

  1. on October 11, 2006 at 9:00 am | Permalink

    Best. Physics Lesson. Evar.

  2. Kat
    on October 11, 2006 at 9:09 am | Permalink

    I’ve been waiting for this rant since last week when I watched the episode. I just sat there thinking to myself “I wonder how long it’ll take Stephen to post a rant about this.” You’re getting slow….

  3. on October 12, 2006 at 1:05 pm | Permalink

    You’re getting slow…

    I believe that they refer to that as “parenthood”. But I did get the verbal of this on Friday night, so hey.

    [See? Reason 985 to move back, Katie.]

  4. on October 12, 2006 at 1:09 pm | Permalink

    It’s true, a good chunk of Friday night conversation was taken up with me ranting about how the nuclear bomb discussion on Jericho was stupid.

    Yes, I am a nerd.

  5. on October 12, 2006 at 2:16 pm | Permalink

    Stephen, have you seen Eric Meyer’s followup from yesterday where he talked about how HYDEsim’s been picked up a bunch lately?

    It’s true, a good chunk of Friday night conversation was taken up with me ranting about how the nuclear bomb discussion on Jericho was stupid.

    Yes, I am a nerd.

    Yes, but so was your audience that night. I mean, really …

  6. on October 12, 2006 at 2:43 pm | Permalink

    It even gets worse. Stephen and I continued talking about it on Tuesday night. Admittedly, it was because of this post causing me to go out and read up on the subject on Wikipedia.

  7. on October 12, 2006 at 6:59 pm | Permalink

    I am … unsurprised. [And I would have been right in the middle of the conversation, I’m sure.]

  8. Karen
    on October 18, 2006 at 2:17 pm | Permalink

    Thanks for the welcome to the TWoPers, Stephen!

    I’ve been waiting for someone to address the idiocy of duct tape and plastic sheeting in the face of nuclear fallout. I wondered if that line had been underwritten by the Department of Homeland Security–Tom Ridge must have been smiling that night!

    The show is so irritating, and the people are all so stupid, that somehow I just can’t tear myself away. It’s like watching a car accident. Mesmerizing.

    But it’s wonderful to hear someone explode the show’s fallacies. Keep it up!

  9. Nicholas
    on October 18, 2006 at 6:40 pm | Permalink

    Another TWoPer here. With respect to the sandlike radioactive detritus, would it settle out quickly or would it be a constant threat, i.e., every time the wind changed direction or simply became strong enough to whip it back into the air, would you have to go back into hiding? I would assume so, but I will defer to the expert.

  10. on October 18, 2006 at 8:25 pm | Permalink

    Even if it’s sitting on the ground, as long as the fallout’s radioactive, it’ll be a threat. Once there’s rain and the fallout gets washed further into the ground, you’ll have more protection. Of course, then you’re in danger of having radioactive particles in the local water table.

    From my reading, what you’re supposed to do is stay in hiding for three or four weeks while the short-lived radioisotopes decay away.

  11. Ted
    on October 19, 2006 at 11:22 pm | Permalink

    I know enough about the tv to know not to trust it – unless it is Bill Moyers then I accept it as gospel. I like the show mostly because I have always had a fantasy about being beaten for causing a ruckus in a purposely dynamated in mine with couple of hundred other townsfolk.

    Really to be upset by it is silly No one should have the idea that the tv people have some duty to be near reality – remember the tv is where most every American gets thier opinion for who to vote for.

  12. on October 20, 2006 at 9:39 am | Permalink

    I generally don’t expect TV or movies to get the science correct, and it’s not like I spend my time muttering, “There’s no sound in space!” every time a spaceship explodes in a mighty thunderous roar. What I’d really like them to do is get the physics wrong in ways that make the plot better or add tension in realistic ways. For instance, the show is pretending that the fallout’s radiation would be gone after the rain, and I’m okay with that because I don’t want to watch three weeks of people sitting in basements.

    When I used to teach physics classes, I liked to use pop culture examples sometimes to make my point. When I taught conservation of energy and conservation of momentum, I used a Weekly World News article about how the Chinese were all going to jump at once and knock the Earth out of its orbit. I’m not teaching classes any more, so I end up writing stuff like this instead.

  13. on October 20, 2006 at 3:06 pm | Permalink

    The old saw is that, inside every engineer, there is a frustrated teacher.

    I refuse to carry this argument to its logical end for fear that Stephen will vaporize me with a laser.

  14. SenorBeef
    on October 21, 2006 at 12:37 am | Permalink

    I’m not defending the science of this show, but…

    His complaint isn’t technically incorrect, but seems to miss the point.

    It’s the particulate matter that emits the radiation (or rather, things attached to/part of it). So the better you can seperate yourself from that particulate matter, the better off you’ll be.

    If you use plastic sheeting to seal your house, then you go hide in the basement, if you’ve done a good job, you’re going to be 10+ feet and several walls/floors between you and the radiation emitting particles. In an unsealed house, the particles could make their way through the house, including the basement, so now you’re surrounded by them and breathing them in, which is a much bigger hazard.

    The level of “ambient” radiation occuring in the days after a nuclear bomb are a bit overstated in popular culture. To my knowledge, just being in the general area of somewhere affected by moderate fallout, say, in a chem suit, isn’t quickly fatal. It’s ingesting the particles that’s the biggest hazard – through air, food, and water.

    So, lacking a dedicated fallout shelter, trying to seal up your house would be a prudent thing to do.

    This seems to tie into the general tendency of people to mock civil defense ideas. “Duck and cover” is brought up mockingly as a ridiculous notion when it’s actually quite practical.

    It stems from the popular conception of nuclear war being a lot more destructive than what actual nuclear would be like. People just assume everyone is going to die, that we have enough nukes to destroy the world “7 times over” (utter nonsense), and that there’s no use in trying to survive.

    The immediate kill zone (95%+ casualties) of a nuclear blast is relatively small. Much bigger is a zone where a relatively smaller number of people will be killed, depending on their circumstances and action. Sure – if a nuclear bomb goes off 10 feet from you, ducking and covering isn’t going to be an option. But if you’re, say, 10 miles away from a 1MT blast? In that case, indoors, you (probably) won’t be killed by the immediate effects of the bomb. However, the blast wave created will propogate out that far (in limited strength) – and a big immediate danger is going to be flying glass. So what do you do to avoid being killed by flying glass? Duck and cover. It could easily make the difference between life and survival for some people.

  15. on October 21, 2006 at 9:34 am | Permalink

    If you use plastic sheeting to seal your house, then you go hide in the basement,

    It’s the last part there that’s the key. Putting empty air between you and the particles isn’t going to do much good. Putting plastic sheeting on your doors and windows and then sitting in your foyer, as two major characters on Jericho did, won’t do you much good.

    Breathing in or swallowing the particles won’t do you any good — you’ll probably get beta burns inside you, and you’ll be carrying around the gamma emitters. But if you don’t have adequate shelter, the end result will be the same.

    Really, if you want to use sheeting, you might as well put it over the door to your basement, since the gamma dose won’t differ much between having some of the fallout inside your house and having it on your roof.

    Either way, though, you’re going to have to get fresh air at some point, and unless your house has some two weeks’ worth of air in it, that air is going to come from outside and will need some filtering.

    The level of “ambient” radiation occuring in the days after a nuclear bomb are a bit overstated in popular culture. To my knowledge, just being in the general area of somewhere affected by moderate fallout, say, in a chem suit, isn’t quickly fatal. It’s ingesting the particles that’s the biggest hazard – through air, food, and water.

    The gamma radiation from fallout doesn’t much differ if it’s inside you or outside you. Wikipedia has a graph of gamma radiation on land 48 hours after the Castle Bravo test, which was the US’s first hydrogen bomb test. At 5 Roentgens/hour, you’ve got about twenty-five to thirty hours cumulative of exposure before you’re going to become disabled due to radiation sickness. The more you get past that, the more likely you are to die. And that 5 R/hr dose occurred up to 150 miles away.

    This seems to tie into the general tendency of people to mock civil defense ideas.

    Perhaps because CD told people to do a lot of things like paint your house and don’t have any books or knick-knacks on the shelves to prevent your house from burning down after a nuclear explosion.

  16. SenorBeef
    on October 21, 2006 at 10:40 am | Permalink

    “It’s the last part there that’s the key. Putting empty air between you and the particles isn’t going to do much good.”

    It’s not just air, though – it’s a few floors, walls, furniture, carpetting … it’s not 2 feet of concrete, but it’s something. Especially if the winds bring you a relatively small amount of fallout, it could easily be the difference between life and death.

    “Putting plastic sheeting on your doors and windows and then sitting in your foyer, as two major characters on Jericho did, won’t do you much good.”

    That was simply stupid. Characters on this show treat radiation and fallout as if it were only the mildest inconvenience. Still, the general idea of sealing your house has some merit.

    “Breathing in or swallowing the particles won’t do you any good — you’ll probably get beta burns inside you, and you’ll be carrying around the gamma emitters. But if you don’t have adequate shelter, the end result will be the same.”

    I don’t have the medical knowledge to really contest this. I can’t imagine breathing in gamma-emitting particles isn’t significantly more harmful than having some 20 feet away on the other side of floors, walls, etc.

    “Really, if you want to use sheeting, you might as well put it over the door to your basement, since the gamma dose won’t differ much between having some of the fallout inside your house and having it on your roof.”

    Somewhat true, but all of the extra random stuff you can cram between you and the emitters is beneficial.

    “Either way, though, you’re going to have to get fresh air at some point, and unless your house has some two weeks’ worth of air in it, that air is going to come from outside and will need some filtering.”

    That’s true – but after a few days, the radiation levels will have decreased significantly. By that time, you could probably enter the main area of the house for moderate periods of time and devise some sort of particle filtration system. It doesn’t have to be fancy – bandanas would probably do.

    “Perhaps because CD told people to do a lot of things like paint your house and don’t have any books or knick-knacks on the shelves to prevent your house from burning down after a nuclear explosion.”

    Well, people seem to mock “duck and cover” unendingly simply on the face of it – but as I explained, it’s quite rational. There’s probably plenty of less useful stuff, too. It mostly stems, though, from the popular conception that nuclear war is just the end – anything you do is futile. I was just trying to convey that nuclear war isn’t what it’s cracked up to be.

  17. Tab Hunter
    on October 21, 2006 at 4:07 pm | Permalink

    Okay first things first, so far as I see it only 8 episodes are listed at the IMDb,so I am wondering if this was ever really intended to be a long drawnout survival series?
    Or was it (as I think it was going to be) going to end up like a mini series version of the movie Testament!
    Now the problem,how do you take something that was originally supposed to last just 6 or 7 hours and turn it into something that lasts for 1 or 2 or even 3 seasons?
    The answer is you make compromises (like the fallout problems) in order to keep the story going and going!
    BTW as far as I can see it looks like the plotline for this show is breaking down into a terrorist attack?
    Only this time they (say a now terrorist controled Pakistan for example) attacks the United States with say a dozen modified passenger airplanes with an A-Bomb concealed in each plane (and timed to go off all at the same instant),which would go a long way to explain the sudden shutdown in the air traffic control system.
    Also it explains the delay in the ICBM launch we see at the end of episode 5 as well!
    Could also explain why people in the know (like those working in the CIA/NSA/DIA) would go into survival mode?

  18. Glaurung
    on October 22, 2006 at 10:53 am | Permalink

    I think the problem with the show’s portrayal of fallout is that it was both understated and overblown.

    Overblown because the fallout from a single bomb in Denver is not going to be lethal to residents of a town in Kansas (300 km away), any more than the fallout from dozens of 50’s Nevada atmospheric tests was lethal to the residents of nearby ranches and towns. (this is especially so if the blast in Denver was an air burst, which is most likely since that’s the most destructive way to do it, but which would generate the least fallout).

    Understated because they portrayed the rainstorm that carried the fallout as being lethal to be in, but then once the rain stopped, they portrayed the radiation as being completely gone (the rain washed it all away!), which is just total nonsense.

    The most likely effect of fallout from the bombing of Denver to people in Kansas would be a large increase in the cancer rate a few years down the line.

    If the show had portrayed bombs going off at military bases, that would be quite another thing, since those would be ground bursts.

  19. on October 22, 2006 at 12:39 pm | Permalink

    Agreed all around. We know they’ve got to be at least 200 miles away from Denver (the distance to the CO/KS border), and probably more — I doubt the fallout would be locally all that bad. I haven’t been able to tell if it was an air burst or a ground burst given what’s been shown. It can’t have been a tremedously high altitude burst, or the EMP would have been nasty. To deal with the longer-term cancer risk, maybe the doctor will have them all drinking iodine cocktails at the bar!

  20. Tab Hunter
    on October 22, 2006 at 5:23 pm | Permalink

    You know with all this talk o fallout it just hit me does anyone know what the protocol is for all the civilian nuclear reactors if we ever got nuked for real?
    Man all the fuel stored at some of them reactor sites could be like a ticking time bombs to anyone who survived!

  21. SenorBeef
    on October 23, 2006 at 1:18 pm | Permalink

    I don’t understand your concern. The fuel is stored safely and would just be left alone in storage in the event of something catastrophic, I’d guess.

  22. Tab Hunter
    on October 26, 2006 at 9:15 pm | Permalink

    Left alone safely for how long Senorbeef???
    A year? 3 years? 10 years? 40 years?

    I mean just for example what if someone living like we did a hundred years ago comes upon an old overgrown NPP 90 years in the post war future, and starts messing with it,exposing stored fuel?

    Taking out fuel and trading it to others thinking it is just a new kind of metal, as by that time who would be around to tell them its dangerous.

    Also does anyone know if nuclear power plants are protected against EMP?

    Heck imagine running at full power then BANG your sitting in the dark control room wondering if anything still works?

    Or even if you can trust anything you see that is still working in order to safely shut down the reactor?

  23. Michael Petch
    on October 29, 2006 at 11:52 am | Permalink

    Someone on IMDB posted a link to this blog. I will comment. Did anyone on the show say that Hawkins was an “expert” or “Physicist” or an “expert” on all things nuclear. He was *trained* post 9/11 (Apparently as a cop but who knows that for sure), and one webisode indicated Hawkins was researching Nuclear weapons on the net weeks prior to the events in Jericho.

    So even if Hawkins was wrong – it doesn’t make the writers wrong. It just makes Hawkins human . Now if you can show me where hawkins claimed to be an expert on the field (and a background in it) – you might have a point.

    The only thign we know is that Hawkins may not understand everything nuclear, nor has anyone (including himself) claimed it as well

  24. on October 29, 2006 at 12:59 pm | Permalink

    So even if Hawkins was wrong – it doesn’t make the writers wrong. It just makes Hawkins human . Now if you can show me where hawkins claimed to be an expert on the field (and a background in it) – you might have a point.

    The only point I have in that section is simple: “Hydrogen bombs literally explode the air” is false. I’m guessing that the writers don’t know the difference, but that’s incidental to this post, and in fact, if you go back and re-read, you’ll see the only reference I make to the writers themselves is a guess that they may be remembering a concern from the Manhattan Project days.

  25. Tab Hunter
    on October 29, 2006 at 4:13 pm | Permalink

    I think that you two are missing the most important point when it comes to Hawkins as you must remember that he is trying to hide what he is from the other townfolk!
    What other way to give yourself away more quickly than to answer a whole lot of questions that obviously you should not be able to know about if you are an excop?
    Remember as well the fireman already looked at him funny (and even went so far as to ask him if he was a professor)when he suggested something to them,so being what looks to me to be a trained Intel officer Hawkins may have answered wrong on purpose in order to throw them off?

  26. SenorBeef
    on November 6, 2006 at 12:42 am | Permalink

    As far as I can tell, the EMP stuff was fairly accurate. A lot of hollywood does that “turned off devices are safe!” nonsense. EMP will also generally leave simple DC circuits alone.

  27. on November 6, 2006 at 8:10 am | Permalink

    Yeah, I joked that Jericho had validated my EMP claims and it made me want to re-check my claims.

  28. Tab Hunter
    on November 6, 2006 at 7:27 pm | Permalink

    You know a few things I noticed so far that were more than a little strange was that the writers did not let even one person in the entire town come up with the idea that it might be a good thing to build some Faraday Cages (even the crazy old guy with the ham radio),at least over the police station and the hospital after the first bombs went off.
    And after the burst I expected to see at least some people using farm equipment as transportation, as the EMP should not have knocked them older model gas and diesel tractors (some of whom you literally start with a hand crank) and the diesel dump trucks used at the mine!

  29. Tab Hunter
    on November 17, 2006 at 4:22 pm | Permalink

    Boy it is as I feared, after this last (9th) episode it looks like Jericho is turning into a 21st century Wild Wild West Horse Opera.
    Wonder when Clint Eastwood will show up with his six shooters?

  30. on November 17, 2006 at 4:37 pm | Permalink

    Ha, yes. They do seem to be headed in that direction.

  31. rae
    on January 1, 2008 at 9:50 am | Permalink

    It’s funny how people nit pick at the WRONG things completely missing the point of everything.
    First off, Jericho is an EXCELLENT drama illustrating various moral dilemmas when people are faced with a complete upturn in their normal social/politcal society. Much like the movie, RED DAWN was in the 80’s–same concept. Second, your main nit pick on the comment from the show about the type of bomb that was used in Denver. Obviously that was to enlighten people to how ignorant the average citizen is about nuclear physics, not to TEACH it. Being hyper critical of a show on that particular issue from someone who CLAIMS TO BE a physicist well…is not very smart. As I stated the dialog in the show had greater signigicance than your superficial view point. And yes, that was meant to be a double entendre as well. Third, the matter of protection from beta and gamma radiation was a point clearly made in the show without using those exact words. The main characters tried to convince the towns people to not hang out in a borded up house but to actually get in the basement. Did most people listen-NO. Must the show go on-YES. And don’t get me started on your assessment the character Stanley drinking the iodine…

  32. on January 3, 2008 at 9:50 am | Permalink

    rae,

    Hawkins’s claim about what fusion bombs do was clearly not a case to show what average citizens think. The show took great pains to set up Hawkins as a character who knows what he’s talking about and is hyper-competent. To turn around and have him spout nonsense about nuclear weapons undercuts that. That makes his dialog fail both factually and dramatically. But nice try! Also, you might want to look up what a double entendre is, since you don’t even seem to have a single one in your rant.

    I’d also love to hear your take on my assessment of Stanley’s iodine swigging. From the logic you’ve displayed so far, I imagine your explanation will be extremely entertaining.

  33. Stan
    on February 18, 2008 at 4:27 am | Permalink

    My half-arsed, hand-waving understanding is:

    Alpha particles are the most dangerous, but penetrate poorly. Gamma rays penetrate well, but do less damage. The only way the alpha particles can do much damage is if you inhale or ingest them. So sealing the house isn’t a terrible idea.

    A better way to explain it is to pass off most of the bad science as bad science from the townsfolk (although I can understand this frustrating a lot of people). After they emerged from their shelters, the Geiger counters weren’t showing any radiation, so I assumed that there wasn’t any fallout carried by the bombs. It was more about the paranoia and terror of the townsfolk.

    If you’re curious about these things, I’d also recommend reading about the downwinders in Utah.

    Oh, and watch “When the wind blows” too. It’s ace!

  34. R.A.
    on August 10, 2010 at 8:32 am | Permalink

    The plastic sheeting is not a “wrong” idea. I used to be a DP (Disaster Preparedness – NBC type) officer in the USAF during the cold war.

    Yes, you have to shield from Gamma however, even a shelter structure with a 90-degree bend from the open end will do just fine since gamma is basically a very high-energy photon and propagates in a strait line. But you will need the sheeting to prevent the fallout from blowing into your survival space.

    You also need to protect from the far lees energetic beta and alpha. Yes skin stops alpha, but if you leave it on the skin you get alpha burns. This is another reason to use sheeting to keep the stuff out of your survival space.

    There are actually two things that do the trick in defense against fallout; shielding, (dirt and concrete being the most expedient) and distance (air gap). Why the center of large structures such as office buildings would make due for an emergency shelter.

    Also you only need to stay in your shelter for about 2 weeks max. There is something called the 7-10 rule for fallout. Since it is so “hot” (that means the isotopes are decaying rapidly) for every seven time periods since the event radiation levels from fallout is divided by ten. E.g., one hour -> seven hours -> 49 hours -> two weeks equals roughly 1000th of the initial radiation at the first hour. This decreases fallout to unshielded survivable levels (other than hotspots) in the surrounding environment.

    Side note – a really basic EMP protection device is water. Take your emergency radios, solar panels, and or other stuff you need to protect (don’t forget an extra alternator for your mechanical ignition vehicle) put them in a water tight metal “can” and sink them in 15 feet of water (a swimming pool would work in a pinch).

    Sorry for the long post – its been a while since I pontificated on this stuff.

  35. on August 10, 2010 at 9:29 am | Permalink

    Interesting! Thanks for the info. Especially the 7/10 rule — that’s a handy rule of thumb.

    It wasn’t plastic sheeting per se that I was so annoyed by, but by them tacking it on the windows and doors and saying, “Hey, we’re fine now.” As you point out, you need shelter from the gamma rays, and being above ground in a regular house won’t help you much there.

  36. R.A.
    on August 10, 2010 at 9:55 am | Permalink

    Arrrgg. Beats head into desk. Strait = straight LOL!

    Glad you like the 7-10 rule. As a physicist, you would totally understand the relationship of how hot (decay rate) something is to its half-life. And yes, a wooden frame single dwelling structure would not cut it no matter how much duct tape and plastic was used. (well only if you wrapped the house to a depth of 40 feet or so I guess. :-))

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  1. By Welcome TWoP Readers « Live Granades on October 17, 2006 at 9:34 pm

    […] Hello, those of you who are visiting from Television Without Pity. This is not really a science blog, nor is it a television blog, but I do sometimes go on about both. For atomic bomb discussion beyond the bit where I grumble about Jericho, you might be interested in Child of the Cold War, which discusses how growing up with the threat of nuclear annihilation made Jericho’s pilot seem better to me than it really was. There’s also the original report from the Manhattan Project scientists determining that a nuclear bomb wouldn’t destroy the entire world. […]

  2. […] Since I grumbled about how Jericho dealt with fallout and nuclear weapons, I should be happy that the CBS show mostly got electromagnetic pulses correct. Right? Right? […]

  3. […] When a show engages me, I glide right past plot holes. I’m actively participating in keeping my belief suspended. As I stop being engaged, though, I become more and more annoyed by inconsistencies. Eventually I reach the point of kicking holes in the story’s walls out of frustration and grumbling about its of physics. […]

  4. […] started the ball rolling when he sent me this link to a blog wherein a physicist nitpicks the goings-on in a new TV series called […]