Survival In THE NUCLEAR ENVIRONMENT (2024)

Safety / Survival / Army Field Manuals / AFM 3-05.70

23-1. Prepare yourself to survive in a nuclear environment. Make sure youknow what to expect and how to react to a nuclear hazard.

EFFECTS OF NUCLEAR WEAPONS

23-2. The effects of nuclear weapons are classified as either initial orresidual. Initial effects occur in the immediate area of the explosion and arehazardous in the first minute after the explosion. Residual effects can last fordays or years and cause death. The principal initial effects are blast andradiation.

Blast

23-3. Blast is the brief and rapid movement of air away from the explosion'scenter and the pressure accompanying this movement. Strong winds accompany theblast. Blast hurls debris and personnel, collapses lungs, ruptures eardrums,collapses structures and positions, and causes immediate death or injury withits crushing effect.

Thermal Radiation

23-4. This effect is the heat and light radiation a nuclear explosion'sfireball emits. Light radiation consists of both visible light and ultravioletand infrared light. Thermal radiation produces extensive fires, skin burns, andflash blindness.

Nuclear Radiation

23-5. Nuclear radiation breaks down into two categories. The effects can beinitial radiation and residual radiation.

23-6. Initial nuclear radiation consists of intense gamma rays and neutronsproduced during the first minute after the explosion. This radiation causesextensive damage to cells throughout the body. Radiation damage may causeheadaches, nausea, vomiting, diarrhea, and even death, depending on theradiation dose received. The major problem in protecting yourself against theinitial radiation's effects is that you may have received a lethal orincapacitating dose before taking any protective action. Personnel exposed tolethal amounts of initial radiation may well have been killed or fatally injuredby blast or thermal radiation.

23-7. Residual radiation consists of all radiation produced after 1 minutefrom the explosion. It has more effect on you than initial radiation. Adiscussion of residual radiation takes place in a subsequent paragraph.

TYPES OF NUCLEAR BURSTS

23-8. There are three types of nuclear bursts: subsurface burst, airburst,and surface burst. The type of burst directly affects your chances of survival.A subsurface burst occurs completely underground or underwater. Its effectsremain beneath the surface or in the immediate area where the surface collapsesinto a crater over the burst's location. Subsurface bursts cause you little orno radioactive hazard unless you enter the immediate area of the crater.

23-9. An airburst occurs in the air above its intended target. The airburstprovides the maximum radiation effect on the target and is, therefore, mostdangerous to you in terms of immediate nuclear effects.

23-10. A surface burst occurs on the ground or water surface. Large amountsof fallout result, with serious long-term effects for you. This type of burst isyour greatest nuclear hazard.

NUCLEAR INJURIES

23-11. Most injuries in the nuclear environment result from the initialnuclear effects of the detonation. These injuries are classed as blast, thermal,or radiation injuries. Further radiation injuries may occur if you do not takeproper precautions against fallout. Individuals in the area near a nuclearexplosion will probably suffer a combination of all three types of injuries.

Blast Injuries

23-12. Blast injuries produced by nuclear weapons are similar to those causedby conventional high-explosive weapons. Blast overpressure can collapse lungsand rupture internal organs. Projectile wounds occur as the explosion's forcehurls debris at you. Large pieces of debris striking you will cause fracturedlimbs or massive internal injuries. Blast overpressure may throw you longdistances, and you will suffer severe injury upon impact with the ground orother objects. Substantial cover and distance from the explosion are the bestprotection against blast injury. Cover blast injury wounds as soon as possibleto prevent the entry of radioactive dust particles.

Thermal Injuries

23-13. The heat and light the nuclear fireball emits cause thermal injuries.First-, second-, or third-degree burns may result. Flash blindness also occurs.This blindness may be permanent or temporary depending on the degree of exposureof the eyes. Substantial cover and distance from the explosion can preventthermal injuries. Clothing will provide significant protection against thermalinjuries. Cover as much exposed skin as possible before a nuclear explosion.First aid for thermal injuries is the same as first aid for burns. Cover openburns (second- or third-degree) to prevent the entry of radioactive particles.Wash all burns before covering.

Radiation Injuries

23-14. Neutrons, gamma radiation, alpha radiation, and beta radiation causeradiation injuries. Neutrons are high-speed, extremely penetrating particlesthat actually smash cells within your body. Gamma radiation is similar to X raysand is also highly penetrating radiation. During the initial fireball stage of anuclear detonation, initial gamma radiation and neutrons are the most seriousthreat. Beta and alpha radiation are radioactive particles normally associatedwith radioactive dust from fallout. They are short-range particles. You caneasily protect yourself against them if you take precautions. See "BodilyReactions to Radiation," below, for the symptoms of radiation injuries.

RESIDUAL RADIATION

23-15. Residual radiation is all radiation emitted after 1 minute from theinstant of the nuclear explosion. Residual radiation consists of inducedradiation and fallout.

Induced Radiation

23-16. This term describes a relatively small, intensely radioactive areadirectly underneath the nuclear weapon's fireball. The irradiated earth in thisarea will remain highly radioactive for an extremely long time. You should nottravel into an area of induced radiation.

Fallout

23-17. Fallout consists of radioactive soil and water particles, as well asweapon fragments. During a surface detonation, or if an airburst's nuclearfireball touches the ground, large amounts of soil and water are vaporized alongwith the bomb's fragments, and forced upward to altitudes of 25,000 meters(82,000 feet) or more. When these vaporized contents cool, they can form morethan 200 different radioactive products. The vaporized bomb contents condenseinto tiny radioactive particles that the wind carries until they fall back toearth as radioactive dust. Fallout particles emit alpha, beta, and gammaradiation. Alpha and beta radiation are relatively easy to counteract, andresidual gamma radiation is much less intense than the gamma radiation emittedduring the first minute after the explosion. Fallout is your most significantradiation hazard, provided you have not received a lethal radiation dose fromthe initial radiation.

BODILY REACTIONS TO RADIATION

23-18. The effects of radiation on the human body can be broadly classed aseither chronic or acute. Chronic effects are those that occur some years afterexposure to radiation. Examples are cancer and genetic defects. Chronic effectsare of minor concern insofar as they affect your immediate survival in aradioactive environment. On the other hand, acute effects are of primaryimportance to your survival. Some acute effects occur within hours afterexposure to radiation. These effects result from the radiation's direct physicaldamage to tissue. Radiation sickness and beta burns are examples of acuteeffects. Radiation sickness symptoms include nausea, diarrhea, vomiting,fatigue, weakness, and loss of hair. Penetrating beta rays cause radiationburns; the wounds are similar to fire burns.

Recovery Capability

23-19. The extent of body damage depends mainly on the part of the bodyexposed to radiation and how long it was exposed, as well as its ability torecover. The brain and kidneys have little recovery capability. Other parts(skin and bone marrow) have a great ability to recover from damage. Usually, adose of 600 centigrays (cGy) to the entire body will result in almost certaindeath. If only your hands received this same dose, your overall health would notsuffer much, although your hands would suffer severe damage.

External and Internal Hazards

23-20. An external or internal hazard can cause body damage. Highlypenetrating gamma radiation or the less penetrating beta radiation that causesburns can cause external damage. The entry of alpha or beta radiation-emittingparticles into the body can cause internal damage. The external hazard producesoverall irradiation and beta burns. The internal hazard results in irradiationof critical organs such as the gastrointestinal tract, thyroid gland, and bone.A very small amount of radioactive material can cause extreme damage to theseand other internal organs. The internal hazard can enter the body either throughconsumption of contaminated water or food or by absorption through cuts orabrasions. Material that enters the body through breathing presents only a minorhazard. You can greatly reduce the internal radiation hazard by using goodpersonal hygiene and carefully decontaminating your food and water.

Symptoms

23-21. The symptoms of radiation injuries include nausea, diarrhea, andvomiting. The severity of these symptoms is due to the extreme sensitivity ofthe gastrointestinal tract to radiation. The severity of the symptoms and thespeed of onset after exposure are good indicators of the degree of radiationdamage. The gastrointestinal damage can come from either the external or theinternal radiation hazard.

COUNTERMEASURES AGAINST PENETRATING EXTERNAL RADIATION

23-22. Knowledge of the radiation hazards discussed earlier is extremelyimportant in surviving in a fallout area. It is also critical to know how toprotect yourself from the most dangerous form of residualradiation—penetrating external radiation.

23-23. The means you can use to protect yourself from penetrating externalradiation are time, distance, and shielding. You can reduce the level ofradiation and help increase your chance of survival by controlling the durationof exposure. You can also get as far away from the radiation source as possible.Finally, you can place some radiation-absorbing or shielding material betweenyou and the radiation.

Time

23-24. Time is important, in two ways, when you are in a survival situation.First, radiation dosages are cumulative. The longer you are exposed to aradioactive source, the greater the dose you will receive. Obviously, spend aslittle time in a radioactive area as possible. Second, radioactivity decreasesor decays over time. This concept is known as radioactive half-life.Thus, a radioactive element decays or loses half of its radioactivity within acertain time. The rule of thumb for radioactivity decay is that it decreases inintensity by a factor of ten for every sevenfold increase in time following thepeak radiation level. For example, if a nuclear fallout area had a maximumradiation rate of 200 cGy per hour when fallout is complete, this rate wouldfall to 20 cGy per hour after 7 hours; it would fall still further to 2 cGy perhour after 49 hours. Even an untrained observer can see that the greatest hazardfrom fallout occurs immediately after detonation, and that the hazard decreasesquickly over a relatively short time. You should try to avoid fallout areasuntil the radioactivity decays to safe levels. If you can avoid fallout areaslong enough for most of the radioactivity to decay, you enhance your chance ofsurvival.

Distance

23-25. Distance provides very effective protection against penetrating gammaradiation because radiation intensity decreases by the square of the distancefrom the source. For example, if exposed to 1,000 cGy of radiation standing 30centimeters (12 inches) from the source, at 60 centimeters (24 inches), youwould only receive 250 cGy. Thus, when you double the distance, radiationdecreases to (0.5)² or 0.25 the amount. While this formula is validfor concentrated sources of radiation in small areas, it becomes morecomplicated for large areas of radiation such as fallout areas.

Shielding

23-26. Shielding is the most important method of protection from penetratingradiation. Of the three countermeasures against penetrating radiation, shieldingprovides the greatest protection and is the easiest to use under survivalconditions. Therefore, it is the most desirable method. If shielding is notpossible, use the other two methods to the maximum extent practical.

23-27. Shielding actually works by absorbing or weakening the penetratingradiation, thereby reducing the amount of radiation reaching your body. Thedenser the material, the better the shielding effect. Lead, iron, concrete, andwater are good examples of shielding materials.

Special Medical Aspects

23-28. The presence of fallout material in your area requires slight changesin first aid procedures. You must cover all wounds to prevent contamination andthe entry of radioactive particles. You must first wash burns of beta radiation,then treat them as ordinary burns. Take extra measures to prevent infection.Your body will be extremely sensitive to infections due to changes in your bloodchemistry. Pay close attention to the prevention of colds or respiratoryinfections. Rigorously practice personal hygiene to prevent infections. Coveryour eyes with improvised goggles to prevent the entry of particles.

SHELTER

23-29. As stated earlier, the shielding material's effectiveness depends onits thickness and density. An ample thickness of shielding material will reducethe level of radiation to negligible amounts.

23-30. The primary reason for finding and building a shelter is to getprotection against the high-intensity radiation levels of early gamma fallout asfast as possible. Five minutes to locate the shelter is a good guide. Speed infinding shelter is absolutely essential. Without shelter, the dosage received inthe first few hours will exceed that received during the rest of a week in acontaminated area. The dosage received in this first week will exceed the dosageaccumulated during the rest of a lifetime spent in the same contaminated area.

Shielding Materials

23-31. The thickness required to weaken gamma radiation from fallout is farless than that needed to shield against initial gamma radiation. Falloutradiation has less energy than a nuclear detonation's initial radiation. Forfallout radiation, a relatively small amount of shielding material can provideadequate protection. Figure 23-1 shows the thickness ofvarious materials needed to reduce residual gamma radiation transmission by 50percent.

Figure 23-1. Materials to Reduce Gamma Radiation

23-32. The principle of half-value layer thickness is useful inunderstanding the absorption of gamma radiation by various materials. Accordingto this principle, if 5 centimeters (2 inches) of brick reduce the gammaradiation level by one-half, adding another 5 centimeters (2 inches) of brick(another half-value layer) will reduce the intensity by another half, namely, toone-fourth the original amount. Fifteen centimeters (6 inches) will reduce gammaradiation fallout levels to one-eighth its original amount, 20 centimeters (8inches) to one-sixteenth, and so on. Thus, a shelter protected by 1 meter (3feet) of dirt would reduce a radiation intensity of 1,000 cGy per hour on theoutside to about 0.5 cGy per hour inside the shelter.

Natural Shelters

23-33. Terrain that provides natural shielding and easy shelter constructionis the ideal location for an emergency shelter. Good examples are ditches,ravines, rocky outcropping, hills, and riverbanks. In level areas withoutnatural protection, dig a fighting position or slit trench.

Trenches

23-34. When digging a trench, work from inside the trench as soon as it islarge enough to cover part of your body thereby not exposing all your body toradiation. In open country, try to dig the trench from a prone position,stacking the dirt carefully and evenly around the trench. On level ground, pilethe dirt around your body for additional shielding. Depending upon soilconditions, shelter construction time will vary from a few minutes to a fewhours. If you dig as quickly as possible, you will reduce the dosage youreceive.

Other Shelters

23-35. While an underground shelter covered by 1 meter (3 feet) or more ofearth provides the best protection against fallout radiation, the followingunoccupied structures (in order listed) offer the next best protection:

• Caves and tunnels covered by more than 1 meter (3 feet) of earth.

• Storm or storage cellars.

• Culverts.

• Basem*nts or cellars of abandoned buildings.

• Abandoned buildings made of stone or mud.

Roofs

23-36. It is not mandatory that you build a roof on your shelter. Build oneonly if the materials are readily available with only a brief exposure tooutside contamination. If building a roof would require extended exposure topenetrating radiation, it would be wiser to leave the shelter roofless. A roof'ssole function is to reduce radiation from the fallout source to your body.Unless you use a thick roof, a roof provides very little shielding.

23-37. You can construct a simple roof from a poncho anchored down with dirt,rocks, or other refuse from your shelter. You can remove large particles of dirtand debris from the top of the poncho by beating it off from the inside atfrequent intervals. This cover will not offer shielding from the radioactiveparticles deposited on the surface, but it will increase the distance from thefallout source and keep the shelter area from further contamination.

Shelter Site Selection and Preparation

23-38. To reduce your exposure time and thereby reduce the dosage received,remember the following factors when selecting and setting up a shelter:

• Where possible, seek a crude, existing shelter that you can improve. Ifnone is available, dig a trench.

• Dig the shelter deep enough to get good protection, then enlarge it asrequired for comfort.

• Cover the top of the fighting position or trench with any readilyavailable material and a thick layer of earth, if you can do so withoutleaving the shelter. While a roof and camouflage are both desirable, it isprobably safer to do without them than to expose yourself to radiationoutside your fighting position.

• While building your shelter, keep all parts of your body covered withclothing to protect it against beta burns.

• Clean the shelter site of any surface deposit using a branch or otherobject that you can discard. Do this cleaning to remove contaminatedmaterials from the area you will occupy. The cleaned area should extend atleast 1.5 meters (5 feet) beyond your shelter's area.

• Decontaminate any materials you bring into the shelter. These materialsinclude grass or foliage that you use as insulation or bedding, and yourouter clothing (especially footgear). If the weather permits and you haveheavily contaminated outer clothing, you may want to remove it and bury itunder a foot of earth at the end of your shelter. You may retrieve it later(after the radioactivity decays) when leaving the shelter. If the clothingis dry, you may decontaminate it by beating or shaking it outside theshelter's entrance to remove the radioactive dust. You may use any body ofwater, even though contaminated, to rid materials of excess falloutparticles. Simply dip the material into the water and shake it to get rid ofthe excess water. Do not wring it out, this action will trap the particles.

• If possible and without leaving the shelter, wash your body thoroughlywith soap and water, even if the water on hand may be contaminated. Thiswashing will remove most of the harmful radioactive particles that arelikely to cause beta burns or other damage. If water is not available, wipeyour face and any other exposed skin surface to remove contaminated dust anddirt. You may wipe your face with a clean piece of cloth or a handful ofuncontaminated dirt. You get this uncontaminated dirt by scraping off thetop few inches of soil and using the "clean" dirt.

• Upon completing the shelter, lie down, keep warm, and sleep and rest asmuch as possible while in the shelter.

• When not resting, keep busy by planning future actions, studying yourmaps, or making the shelter more comfortable and effective.

• Don't panic if you experience nausea and symptoms of radiation sickness.Your main danger from radiation sickness is infection. There is no first aidfor this sickness. Resting, drinking fluids, taking any medicine thatprevents vomiting, maintaining your food intake, and preventing additionalexposure will help avoid infection and aid recovery. Even small doses ofradiation can cause these symptoms, which may disappear in a short time.

Exposure Timetable

23-39. The following timetable provides you with the information needed toavoid receiving a serious dosage and still let you cope with survival problems:

• Complete isolation from 4 to 6 days following delivery of the lastweapon.

• A very brief exposure to get water on the third day is permissible, butexposure should not exceed 30 minutes.

• One exposure of not more than 30 minutes on the seventh day.

• One exposure of not more than 1 hour on the eighth day.

• Exposure of 2 to 4 hours from the ninth day through the twelfth day.

• Normal operation, followed by rest in a protected shelter, from thethirteenth day on.

• In all instances, make your exposures as brief as possible. Consider onlymandatory requirements as valid reasons for exposure. Decontaminate at everystop.

23-40. The times given above are conservative. If forced to move after thefirst or second day, you may do so. Make sure that the exposure is no longerthan absolutely necessary.

WATER PROCUREMENT

23-41. In a fallout-contaminated area, available water sources may becontaminated. If you wait at least 48 hours before drinking any water to allowradioactive decay to take place and select the safest possible water source, youwill greatly reduce the danger of ingesting harmful amounts of radioactivity.

23-42. Although many factors (wind direction, rainfall, sediment) willinfluence your choice in selecting water sources, consider the followingguidelines.

Safest Water Sources

23-43. Water from springs, wells, or other underground sources that undergonatural filtration will be your safest sources. Any water found in the pipes orcontainers of abandoned houses or stores will also be free from radioactiveparticles. This water will be safe to drink, although you will have to takeprecautions against bacteria in the water.

23-44. Snow taken from 15 centimeters (6 inches) or more below the surfaceduring the fallout is also a safe source of water.

Streams and Rivers

23-45. Water from streams and rivers will be relatively free from falloutwithin several days after the last nuclear explosion because of dilution. Ifpossible, filter such water before drinking to get rid of radioactive particles.The best filtration method is to dig sediment holes or seepage basins along theside of a water source. The water will seep laterally into the hole through theintervening soil that acts as a filtering agent and removes the contaminatedfallout particles that settled on the original body of water. This method canremove up to 99 percent of the radioactivity in water. You must cover the holein some way to prevent further contamination. See Figure6-9 for an example of a water filter.

Standing Water

23-46. Water from lakes, pools, ponds, and other standing sources is likelyto be heavily contaminated; though most of the heavier, long-lived radioactiveisotopes will settle to the bottom. Use the settling technique to purify thiswater. First, fill a bucket or other deep container three-fourths full withcontaminated water. Then take dirt from a depth of 10 centimeters (4 inches) ormore below the ground surface and stir it into the water. Use about 2.5centimeters (1 inch) of dirt for every 10 centimeters (4 inches) of water. Stirthe water until you see most dirt particles suspended in the water. Let themixture settle for at least 6 hours. The settling dirt particles will carry mostof the suspended fallout particles to the bottom and cover them. You can thendip out the clear water. Purify this water using a filtration device.

Additional Precautions

23-47. As an additional precaution against disease, treat all water withwater purification tablets from your survival kit or boil it.

FOOD PROCUREMENT

23-48. Obtaining edible food in a radiation-contaminated area is a seriousbut not insurmountable problem. You need to follow a few special procedures inselecting and preparing rations and local foods for use. Since secure packagingprotects your combat rations, they will be perfectly safe for use. Supplementyour rations with any food you can find on trips outside your shelter.

Abandoned buildings may have stores of processed foods. They are safe for useafter decontaminating them. Canned and packaged foods should have containers orwrappers removed or washed free of fallout particles. These processed foods alsoinclude food stored in any closed container and food stored in protected areas(such as cellars). All such foods must be washed before eating or handling them.

23-49. If little or no processed food is available in your area, you may haveto supplement your diet with local food sources. Animals and plants are localfood sources.

Animals—A Food Source

23-50. Assume that all animals, regardless of their habitat or livingconditions, were exposed to radiation. The effects of radiation on animals aresimilar to those on humans. Thus, most of the wild animals living in a falloutarea are likely to become sick or die from radiation during the first monthafter the nuclear explosion. Although animals may not be free from harmfulradioactive materials, you can and must use them in survival conditions as afood source if other foods are not available. With careful preparation and byfollowing several important principles, animals can be safe food sources.

23-51. First, do not eat an animal that appears to be sick. It may havedeveloped a bacterial infection because of radiation poisoning. Contaminatedmeat, even if thoroughly cooked, could cause severe illness or death if eaten.

23-52. Carefully skin all animals to prevent any radioactive particles on theskin or fur from entering the body. Do not eat meat close to the bones andjoints as an animal's skeleton contains over 90 percent of the radioactivity.However, the remaining animal muscle tissue will be safe to eat. Before cookingit, cut the meat away from the bone, leaving at least a 3-millimeter (1/8-inch)thickness of meat on the bone. Discard all internal organs (heart, liver, andkidneys) since they tend to concentrate beta and gamma radioactivity.

23-53. Cook all meat until it is very well done. To be sure the meat is welldone, cut it into less than 13-millimeter-thick (4 1/2-inch-thick) pieces beforecooking. Such cuts will also reduce cooking time and save fuel.

23-54. The extent of contamination in fish and aquatic animals will be muchgreater than that of land animals. This is also true for water plants,especially in coastal areas. Use aquatic food sources only in conditions ofextreme emergency.

23-55. All eggs, even if laid during the period of fallout, will be safe toeat. Completely avoid milk from any animals in a fallout area because animalsabsorb large amounts of radioactivity from the plants they eat.

Plants—A Food Source

23-56. Plant contamination occurs by the accumulation of fallout on theirouter surfaces or by absorption of radioactive elements through their roots.Your first choice of plant food should be vegetables such as potatoes, turnips,carrots, and other plants whose edible portion grows underground. These are thesafest to eat once you scrub them and remove their skins.

23-57. Second, in order of preference, are those plants with edible partsthat you can decontaminate by washing and peeling their outer surfaces. Examplesare bananas, apples, tomatoes, prickly pears, and other such fruits andvegetables.

23-58. Any smooth-skinned vegetable, fruit, or plant that you cannot easilypeel or effectively decontaminate by washing will be your third choice ofemergency food.

23-59. The effectiveness of decontamination by scrubbing is inverselyproportional to the roughness of the fruit's surface. Smooth-surfaced fruitswill lose 90 percent of their contamination after washing, but rough-surfacedplants will lose only about 50 percent.

23-60. Eat rough-surfaced plants (such as lettuce) only as a last resortbecause you cannot effectively decontaminate them by peeling or washing. Otherdifficult foods to decontaminate by washing with water include dried fruits(figs, prunes, peaches, apricots, pears) and soybeans.

23-61. In general, you can use any plant food that is ready for harvest ifyou can effectively decontaminate it. However, growing plants can absorb someradioactive materials through their leaves as well as from the soil, especiallyif rains have occurred during or after the fallout period. Avoid using theseplants for food except in an emergency.

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