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Well i was thinking about this last week and today ...

I've been looking for information on how many days / weeks / months after a nuclear attack ( inc fallout ) it would take before it would be safe to venture outside ( safe radiation levels and such ) ?

At the moment im guessing on about 2 months ...

can anyone help me with this ?

Thanks

AK.
 

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Fallout from 'regular' nuclear weapons, shortly after the detonation, begins to decay at the rate of a ten-fold decrease for each seven-fold increase in time.

As an example, after the fallout has stopped and the level peaked, the base line reading is an hour later. Say it is 1,000 R, seven hours later (1X7) it will be down to 100. After another 49 hours (7x7) it will be down to 10. 343 hours later (7x7x7 or 14 more days) the radiation should be down to 1. That is still too high to do more than go out for a few minutes to check things. You need to wait until the level is 0.01 before venturing out and staying out, though if needed, some time can be spent outside during the day if most of the time is spent in a shelter.

While 1000 R is a realistic starting number, many places won't have nearly that much and the time in shelter will be much less, if you have a good shelter. The less you are taking while in the shelter, the more you can take outside for a few minutes.

I hope this helps. If you have more questions, please feel free to ask.
 

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Here is the vague answer to your question:

"Both the local and worldwide fallout hazards of nuclear explosions depend on a variety of interacting factors: weapon design, explosive force, altitude and latitude of detonation, time of year, and local weather conditions."

This is from the article linked below that gives information on how these factors influence the level of contamination, it will allow you to educate yourself on these factors and make a real-life determination in the event of nuclear attack. I suggest you print it off and keep it in your survival library.

Here is the specific answer:

http://www.atomicarchive.com/Docs/Effects/wenw_chp2.shtml

For further Nuclear education:

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1936905

http://www.sciencedaily.com/releases/2007/07/070725143452.htm
 

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There are basically two types of fallout.

Heavy fallout is made up of heavy radioisotopes that are long lived. Their half lives vary from a few months to several decades. Even with the largest bombs this type of fallout is not spread out over a wide area and will basically fall out within a few hours of the blast and in a predictable oval pattern away from the site of the explosion. The size and shape of this pattern is dependent on the size and type of nuke, as well as weather patterns.

If you are in an area that gets significant heavy fallout you are dead if you don't get out very very quickly. Within a few months, the radiation will fall off quickly as the radioactive particles are absorbed into the ground and/or decay into nothing. The areas closets to the blast site that get the heaviest concentration of heavy fallout will be uninhabitable for something like 2 or 3 months and dangerous to live in for maybe 2 or 3 years.

The second type is "light" fallout. The major constituent of this is Iodine 131. Iodine 131 has a half life of 8 days and will be spread out over hundreds of thousands of square miles. This means that if you have one curie worth of Iodine 131 at zero hour, at the end of the eighth day you will only have 1/2 curie. The rest of the Iodine 131 has now decayed into Cesium 131, a mildly toxic metal that is not radioactive.

Iodine 131 is very dangerous to organisms with a long lifespan such as humans. The reason for this is it will concentrate in the Thyroid gland and bathe it with very high levels of beta radiation, causing hyperthyroidism, hypothyroidism, thyroid cancers, etc. In adults this is not a great concern, because by the time these symptoms show up most adults will be old, but in children, with their highly active metabolisms, it will wreak havoc.

Animals that eat or inhale Iodine 131 will most often die before the symptoms have a chance to show themselves so it is not a major problem with them. Just don't drink cows milk, or eat the meat until the Iodine 131 has decayed for at least 10 half lives or 80 days and your farm animals should be fine.

At the end of 80 days, the Iodine 131 has statistically disappeared.

So if you are not in the blast zone, and not in the area of heavy fallout, you should endeavor to stay inside your home or shelter for 80 days. In practice however this is almost impossible so you might be able to go outside if you wore a M95 type respirator that was fitted and worn correctly. Even then I would not allow my children outside at all for the entire 80 days.

There are those, especially in the left wing media who would have you believe that life would cease to exist after a Nuclear War, but just look at Hiroshima. The city was rebuilt just months after the bombing and literally dozens of long terms cancer studies have concluded that the cancer rate for the inhabitants of the city is statistically no different that anywhere else in Japan or the world.
 

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the ready store has potassium iodide you can use to keep the iodine out of your thyroid. also, i found once on worldnetdaily.com a useful explanation of how to survive a nuclear bomb. it explained a lot of things like how long to stay inside.
 

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...Even with the largest bombs this type of fallout is not spread out over a wide area and will basically fall out within a few hours of the blast and in a predictable oval pattern away from the site of the explosion. The size and shape of this pattern is dependent on the size and type of nuke, as well as weather patterns...
This pattern is only "predictable" when knowing all of the included factors and almost never oval...

...The areas closets to the blast site that get the heaviest concentration of heavy fallout will be uninhabitable for something like 2 or 3 months and dangerous to live in for maybe 2 or 3 years...
A more accurate range would be from a few months to a few decades... Again, depending entirely on all of the variables involved.

...In practice however this is almost impossible so you might be able to go outside if you wore a M95 type respirator that was fitted and worn correctly. Even then I would not allow my children outside at all for the entire 80 days...
Any respirator will only protect you from airborne particulates. This does nothing to mitigate the effects of absorption of toxic metals. It also does nothing to prevent the penetration of most types of harmful radiation.

...just look at Hiroshima. The city was rebuilt just months after the bombing and literally dozens of long terms cancer studies have concluded that the cancer rate for the inhabitants of the city is statistically no different that anywhere else in Japan or the world.
I would like to see these studies.
 

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This pattern is only "predictable" when knowing all of the included factors and almost never oval...
True.

A more accurate range would be from a few months to a few decades... Again, depending entirely on all of the variables involved.
Not decades at all.
Upward of a year is likely.
See Cresson Kearny

As already listed above....



Any respirator will only protect you from airborne particulates. This does nothing to mitigate the effects of absorption of toxic metals. It also does nothing to prevent the penetration of most types of harmful radiation.
Absolutely true.



I would like to see these studies.
Actually I recall reading the incidences of Leukemia and many other non cancer blood and reproductive maladies had in fact increased significantly.

decay is typically based on the half-life.
I think it's the other way around, decay, being the gradual loss of emitted energy is the dictator of half life.
 

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Half Life:

t(1/2) = ln(2) / [Decay Constant (lambda)] :cool:

Check this out: (For Natural Uranium)

Isotope---- Percent------Half-Life-------Amount present---Isotope's
----------------------------------------In 1g Sample----Decay Rate
---------------------------------------------------------Constant
U-238_____99.3%_____4.51x109 years__9.93x10-1 g_____1.54x10-10
U-235_____0.724%____7.10x108 years__7.24x10-3_______9.76x10-10
U-234_____0.0057%___2.47x105 years__5.70x10-5 g_____2.81x10-6

:thumb:
 
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