DOCTRINAL REFERENCE — FM 3-11 §1-61 through 1-63: Nuclear weapon effects are qualitatively different from biological or chemical weapon effects. The nature and intensity of detonation effects are determined by weapon type, yield, and physical medium of detonation. Energy releases as blast, thermal radiation, prompt radiation, and electromagnetic pulse.
NUCLEAR
DELIVERY: ICBM / SLBM / CRUISE MISSILE / GRAVITY BOMB / TACTICAL WARHEAD
PRIMARY EFFECTS: BLAST • THERMAL • PROMPT RADIATION • EMP • FALLOUT
Weapon Types
Fission Device (Atomic Bomb)
A-Bomb • Fission Weapon • "Little Boy" / "Fat Man" class
MechanismNuclear fission — heavy atom nucleus splits, chain reaction releases energy
Yield range1 kiloton (tactical) to ~500 kt (strategic)
Hiroshima ref~15 kt of TNT equivalent; 80,000 killed instantly
Energy split50% blast, 35% thermal, 15% nuclear radiation
Fallout riskModerate; higher with surface burst vs. airburst
LETHAL
BLAST
EMP
Thermonuclear Device (H-Bomb)
Hydrogen Bomb • Fusion Weapon • Three-stage weapon
MechanismFission primary ignites fusion fuel; fission-fusion-fission sequence in fractions of a second
Yield range100 kt to 50+ megatons
Tsar Bomba50 Mt — largest ever tested; 3,800x Hiroshima
Modern statusVirtually all strategic warheads (US, Russia, China, France) are thermonuclear
Fallout riskExtreme; surface burst creates massive fallout plume
LETHAL
MASS CASUALTY
PERSISTENT FALLOUT
Tactical Nuclear Weapon
TNW • Non-strategic Nuclear Weapon • Battlefield Nuke
Yield rangeSub-kiloton to ~50 kt; designed for battlefield use
DeliveryArtillery shells, short-range missiles, torpedoes, air-delivered bombs
NationsRussia (~2,000 active), USA, potentially China, India, Pakistan, North Korea
Threat noteMost likely first-use nuclear scenario; lower yield but still catastrophic
LETHAL
TACTICAL
MODERATE FALLOUT
Improvised Nuclear Device
IND • CRBN Improvised Device
Yield range0.01 to ~10 kt; highly variable based on design
Source materialWeapon-grade HEU or Pu-239; requires ~15 kg U-235 or ~5 kg Pu-239 for criticality
Threat actorNation-state or well-resourced non-state actor
DistinctionUnlike dirty bomb (RDD), IND produces actual nuclear yield
LETHAL
TERRORISM VECTOR
Burst Types & Effects
| Burst Type | Altitude | Primary Effect | Fallout Production | Likely Target |
| Air Burst | Thousands of feet AGL | Maximum blast/thermal damage radius; reflects off ground increasing destructive power | Minimal — most fallout dissipates at altitude | Cities; large population centers; maximize casualties |
| Surface Burst | At or near ground level | Cratering; massive quantities of earth/debris irradiated and lofted | Extreme — produces dense local and downwind fallout field | Hardened silos; command bunkers; bridges; dams |
| Sub-Surface Burst | Below ground | Cratering; seismic effect; strong ground shock | Extreme — nearly all fallout deposited locally | Deep hardened bunkers; underground facilities |
| High Altitude Burst (HEMP) | 30+ miles (50+ km) | Minimal blast/thermal at surface; massive EMP covering continental scale | Negligible surface fallout | Electronic infrastructure; power grid; communications; GPS |
| Underwater Burst | Below water surface | Highly radioactive base surge; contaminated water column | High — radiological contamination of water | Naval targets; port facilities |
Effect Rings — 1-Megaton Surface Burst (Reference)
Source: Kobler & Dutra, Nuclear War Survival: A One Hour Crash Course (2022). Adjust proportionally for smaller yields. A 100-kt weapon produces effects at roughly 1/3 these distances.
1-Megaton Surface Burst — Effect Radius Table
ZONE 1Fireball — r:4,000 ftEverything vaporized. Core temp 100 million °C. Not survivable.
ZONE 2Severe blast — r:1.7 mi20 PSI overpressure. Heavy concrete demolished. Fatal to exposed personnel.
ZONE 3Moderate blast — r:2.8 mi5 PSI overpressure. Wood frame homes collapse. Extreme injury from debris.
ZONE 4Thermal/burn — r:7.5 mi1st-3rd degree burns. All combustibles ignite. Firestorm possible.
ZONE 5Blast wave — r:7.5 miGlass shatters. Blast wave at 784 mph; 158 mph winds at 3.7 mi radius.
ZONE 6Flash blindness — r:13 mi (day)Flash blindness — day. Up to 53 miles at night. Do not look at flash.
ZONE 7Fallout plume — up to 238 miLethal fallout downwind (15 mph wind). 25 mi downwind: 600 rad if unsheltered within 25 min.
Electromagnetic Pulse (EMP)
HEMP THREAT: A single thermonuclear weapon detonated at 30+ miles altitude above the continental US center could generate an EMP field covering the entire lower 48 states. EMP creates thousands of volts in connected systems vs. thousandths of a volt for radio signals. Most lightning protection does NOT guard against EMP.
| Component | Effect | Mitigation |
| Power grid / long lines | Induced surge causes transformer destruction; extended outage possible | Faraday enclosures; surge protectors (limited); unplug during attack |
| Vehicle electronics | Post-1980 vehicles may be disabled; older vehicles (pre-computer) more resilient | Keep older backup vehicle; avoid driving during/after nuclear detonation |
| Communications | Radios, cell towers, repeaters damaged; may permanently disable ham infrastructure | EMP-shielded gear in Faraday cage; keep spare HT in metal ammo can lined with foam |
| Medical devices | Pacemakers, insulin pumps, implanted electronics at risk | No reliable mitigation; medical contingency planning required |
| Human body | Minimal direct risk to unshielded human body from EMP alone | N/A — not a direct physiological threat |
DOCTRINAL REFERENCE — FM 3-11 §1-47 through 1-50: Chemical warfare agents are designed to kill or severely incapacitate personnel. Classified by physiological action: nerve, blood, blister, choking, and incapacitating agents. May be persistent (hours+) or non-persistent (minutes).
CHEMICAL
DELIVERY: ARTILLERY • MISSILES • AIRCRAFT SPRAY • IMPROVISED DEVICE • TIC RELEASE
STATE: VAPOR • LIQUID • AEROSOL • SOLID
Nerve Agents (G-Series / V-Series)
Sarin
GB • NATO code GB • Isopropyl methylphosphonofluoridate
MechanismOrganophosphate; inhibits acetylcholinesterase; acetylcholine accumulates at nerve synapses
Physical stateColorless liquid; low boiling point; evaporates quickly
OnsetSeconds to minutes (vapor exposure); minutes to hours (skin contact)
SignsSLUDGE: Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis; also miosis (pin-point pupils), seizures, respiratory failure
PersistenceNon-persistent — dissipates within minutes to hours
TreatmentAtropine + 2-PAM (pralidoxime); decon with copious water
LETHAL
NON-PERSISTENT
VAPOR HAZARD
Soman
GD • Pinacolyl methylphosphonofluoridate
MechanismSame as Sarin; also "ages" rapidly — antidote must be given within 2 minutes of exposure
Physical stateColorless liquid; slightly fruity odor
Key differenceFastest aging nerve agent; severely limits treatment window
SignsSame SLUDGE pattern; miosis; seizures; apnea
TreatmentAtropine immediately; 2-PAM largely ineffective after aging occurs
LETHAL
RAPID AGING
NON-PERSISTENT
VX
V-Agent • O-Ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate
MechanismOrganophosphate; acetylcholinesterase inhibitor; primary skin absorption hazard
Physical stateOily, amber-colored liquid; low volatility
OnsetMinutes to hours; skin route slower but highly effective
Key differenceMost persistent nerve agent; remains on surfaces/terrain for days to weeks
Lethal dose~10 mg skin contact lethal to 50% of exposed (LD50)
TreatmentAtropine + 2-PAM; DECON critical — remove all clothing, flush with water/bleach
LETHAL
PERSISTENT
SKIN HAZARD
Novichok (4th Gen)
A-230 / A-232 / A-234 class • Nontraditional Agent
MechanismPotent acetylcholinesterase inhibitor; more potent than VX by estimated 5-10x
OriginSoviet/Russian development; outside Chemical Weapons Convention schedules
Key noteFM 3-11 §1-50: nontraditional agents present unique challenges to CBRN defense; may defeat existing antidotes
Use historyUsed by Russia for targeted assassinations (Skripal, UK 2018; Navalny, 2020)
LETHAL
4TH GEN
TREATMENT UNCERTAIN
Blister Agents (Vesicants)
Sulfur Mustard
HD • Mustard Gas • Yperite • Yellow Cross
MechanismAlkylating agent; damages DNA; destroys skin, eyes, mucous membranes
Physical stateOily liquid; slight garlic/mustard odor; may appear yellow-brown
OnsetDelayed 2-24 hours; no immediate pain — exposure may not be detected
SignsLarge fluid-filled blisters on skin; eye inflammation/blindness; airway damage; bone marrow suppression
PersistenceHighly persistent in cold weather; days to weeks in soil/structures
TreatmentNo antidote; immediate decon; treat like burn injury; supportive care
Combat useWWI Germany; Iraq vs. Iran and Kurds (1980s); Syria (2015-2018)
INCAPACITATING
PERSISTENT
NO ANTIDOTE
Lewisite
L • 2-Chlorovinyldichloroarsine
MechanismArsenical vesicant; inhibits cellular enzymes; immediate pain on contact
Physical stateOily liquid; geranium-like odor
Key difference vs. mustardImmediate burning sensation on contact (vs. mustard's delayed onset); faster acting
SignsImmediate eye/skin pain; blistering; airway irritation; systemic arsenic toxicity
TreatmentBritish Anti-Lewisite (BAL/dimercaprol) is antidote; immediate decon
INCAPACITATING
ANTIDOTE EXISTS
IMMEDIATE SYMPTOMS
Blood & Choking Agents
Hydrogen Cyanide
AC • HCN • Prussic Acid • Zyklon B precursor
MechanismInhibits cytochrome oxidase; cells cannot use oxygen; causes rapid cellular asphyxiation
Physical stateGas; faint bitter almond odor (not detectable by ~40% of population)
OnsetSeconds to minutes
SignsRapid breathing, dizziness, headache, bright red venous blood, seizures, rapid death at high dose
PersistenceNon-persistent; disperses rapidly
TreatmentAmyl nitrite inhalant; sodium nitrite + sodium thiosulfate IV; hydroxocobalamin
LETHAL
NON-PERSISTENT
ANTIDOTE EXISTS
Phosgene
CG • Carbonyl Dichloride • Mustard Gas of WWI choking agents
MechanismReacts with lung tissue; destroys alveolar-capillary membrane; pulmonary edema
Physical stateColorless gas; fresh cut hay / green corn odor
OnsetDelayed 2-24 hours; initial symptoms mild — "delayed lethality" is primary danger
SignsMild irritation initially; delayed pulmonary edema; frothy sputum; cyanosis; death by asphyxia
Historical noteCaused ~80% of chemical warfare deaths in WWI
TreatmentNo antidote; strict rest (exertion worsens); supportive care; supplemental O2
LETHAL
DELAYED LETHALITY
NO ANTIDOTE
Toxic Industrial Chemicals (TIC)
FM 3-11 §1-48: TICs are any chemicals developed, manufactured, used, transported, or stored by industrial, agricultural, medical, or commercial processes which could pose a hazard. Chlorine, ammonia, and hydrogen fluoride represent common TIC threats near industrial corridors. Risk of TIC weaponization depends on severity of effects and probability of obtaining and releasing dangerous quantities.
| Agent | Primary Hazard | Signs/Symptoms | Immediate Action |
| Chlorine | Choking; pulmonary damage | Burning eyes/throat; coughing; choking; yellow-green cloud; bleach odor | Evacuate upwind; shelter in place above grade; flush eyes/skin with water |
| Ammonia | Corrosive; respiratory | Intense nasal/throat irritation; coughing; pungent odor; pulmonary edema at high dose | Evacuate; flush with water; do NOT induce vomiting if ingested |
| Hydrogen Fluoride | Corrosive; systemic fluoride toxicity | Severe burns not initially painful; systemic hypocalcemia; cardiac arrhythmia | Calcium gluconate gel to affected area; immediate medical care |
| Chlorine Trifluoride | Extreme oxidizer; fire risk | Severe burns; ignites most materials spontaneously; extremely hazardous | Full PPE; avoid water; evacuate immediately |
DOCTRINAL REFERENCE — FM 3-11 §1-51 through 1-55: Biological hazards include pathogens (bacteria, viruses, fungi) and toxins. Key tactical advantages: clandestine employment, delayed onset, detection difficulty, potential communicability. Small doses can produce lethal or incapacitating effects over extensive areas.
BIOLOGICAL
DELIVERY: AEROSOL • VECTOR (INSECTS) • CONTAMINATED FOOD/WATER • DIRECT CONTACT
PATHOGEN TYPES: BACTERIAL • VIRAL • FUNGAL • TOXIN
Category A Agents (Highest Priority — Mass Casualty Potential)
Anthrax
Bacillus anthracis • Inhalation / Cutaneous / GI forms
TypeBacterial (spore-forming); spores survive decades in soil
TransmissionNOT person-to-person; inhalation (weaponized aerosol), skin contact, ingestion
Incubation1-5 days (inhalation); up to 60 days possible
Signs (inhaled)Initial: flu-like; then severe respiratory distress, mediastinal widening on X-ray, septic shock; ~80% fatal if untreated
TreatmentCiprofloxacin, Doxycycline, Amoxicillin; antitoxin if available; vaccine prophylaxis
WeaponizationUsed in 2001 US mail attacks; Soviet Sverdlovsk accident (1979); requires specialized production
LETHAL
NON-CONTAGIOUS
TREATABLE
Smallpox
Variola major • Variola minor
TypeViral (orthopoxvirus); eradicated in wild 1980; stockpiles in US/Russia only (officially)
TransmissionHighly contagious person-to-person; respiratory droplets; direct contact with lesions
Incubation7-17 days (average 12)
SignsHigh fever; then synchronous deep pustular rash (ALL blisters same stage — unlike chickenpox); concentrated on face/extremities
Fatality30% unvaccinated (Variola major); up to 90% in isolated/unvaccinated populations historically
TreatmentNo reliable curative treatment; Tecovirimat (TPOXX) antivirals; vaccine effective pre-exposure or within 4 days of exposure
Key noteMost of US population unvaccinated since 1972; FEMA maintains national stockpile
LETHAL
HIGHLY CONTAGIOUS
VACCINE AVAILABLE
Pneumonic Plague
Yersinia pestis • Black Death • Pneumonic form
TypeBacterial; pneumonic form (lung infection) most dangerous weaponized variant
TransmissionHighly contagious person-to-person via respiratory droplets (pneumonic form)
Incubation1-3 days
SignsRapid onset fever, weakness, shortness of breath, bloody cough, pneumonia; death in 2-4 days untreated; NO buboes (groin/armpit swellings) unlike bubonic form
TreatmentDoxycycline, Tetracycline, Ciprofloxacin, IV Gentamycin; oxygen support; strict respiratory isolation
LETHAL
CONTAGIOUS
TREATABLE
Viral Hemorrhagic Fever
VHF • Ebola / Marburg / Lassa / Crimean-Congo class
TypeViral; multiple families (Filoviridae, Arenaviridae, Bunyaviridae)
TransmissionDirect contact with bodily fluids; some via respiratory route; high infectivity at low dose
Incubation2-21 days depending on agent
SignsFever, diarrhea, weakness progressing to hemorrhage — bleeding from eyes, ears, nose, mouth, rectum; subcutaneous bruising; multi-organ failure
FatalityEbola: up to 90% untreated; Lassa: ~1% in endemic area (most asymptomatic); weaponized aerosol increases risk
TreatmentSupportive care; experimental antivirals (remdesivir, ZMapp for Ebola); strict contact/droplet precautions; full PPE
LETHAL
CONTAGIOUS (fluids)
LIMITED TREATMENT
Biological Toxins (Non-Living Weapons)
Botulinum Toxin
Type A-G • Most potent toxin known • Clostridium botulinum byproduct
MechanismBlocks neuromuscular junction; prevents acetylcholine release; descending flaccid paralysis
Onset12-36 hours (food); 12-24 hours (inhaled aerosol)
SignsDescending paralysis: double vision, slurred speech, dysphagia, then respiratory failure; afebrile; alert
CommunicableNOT person-to-person (toxin only, not live bacteria)
TreatmentHeptavalent antitoxin (HBAT); mechanical ventilation; supportive care; no antibiotics helpful once toxin released
LETHAL
NON-CONTAGIOUS
DELAYED ONSET
Ricin
Castor bean toxin • Ricinus communis extract
MechanismInhibits protein synthesis; inactivates ribosomes; causes cell death
RoutesInjection (most lethal); inhalation; ingestion (less effective due to GI absorption barriers)
Lethal dose~3 mg inhaled lethal to average adult; 1 castor bean potentially fatal to child if chewed
SignsInhaled: respiratory distress 4-8 hrs; pulmonary edema, fever, shock; Ingested: nausea, vomiting, internal bleeding
TreatmentNo antidote; supportive care only; decon with soap/water
LETHAL
NO ANTIDOTE
READILY PRODUCED
Attack Indicator & Differentiation Reference
| Indicator | Natural Outbreak | Deliberate Attack |
| Case clustering | Geographic spread over time; follows epidemiological curve | Simultaneous onset in multiple geographic areas; explosion of cases |
| Agent type | Endemic agents; seasonal patterns | Unusual agent for region; eradicated pathogen (smallpox); unusual route |
| Population affected | Affects vulnerable populations first (elderly, immunocompromised) | All demographics affected equally; healthy young adults as casualties |
| Animal involvement | Zoonotic diseases show concurrent animal die-off | Humans only; or deliberate animal contamination to mask attack |
| Downwind pattern | No consistent directional spread | Cases follow prevailing wind; aligned with release point |
| Antibiotic resistance | Normal resistance patterns | May show engineered resistance; unusual drug resistance profile |
DOCTRINAL REFERENCE — FM 3-11 §1-56 through 1-60: Radiological hazards include any source of nuclear radiation that produces ions causing damage, injury, or destruction. Radiological dispersal devices (RDD) and radiological exposure devices (RED) are the primary non-nuclear radiological weapon types.
RADIOLOGICAL
DEVICE TYPES: RDD (DIRTY BOMB) • RED (EXPOSURE DEVICE) • INDUSTRIAL SOURCE RELEASE
PRIMARY EFFECT: CONTAMINATION • DENIAL • PANIC • LONG-TERM CANCER RISK
Radiological Device Types
Radiological Dispersal Device
RDD • Dirty Bomb • Improvised Radiological Device
MechanismConventional explosive disperses radioactive material over wide area; contamination rather than nuclear yield
Primary effectContamination of area; economic disruption; psychological terror; long-term cancer risk
Immediate riskConventional blast casualties nearest device; radiation exposure secondary concern in most scenarios
Source materialsMedical/industrial sources: Cesium-137, Cobalt-60, Iridium-192, Strontium-90
FM 3-11 noteAvoidance is most effective individual protective measure; disperse from area upwind
CONTAMINATION
AREA DENIAL
ACCESSIBLE MATERIALS
Radiological Exposure Device
RED • Hidden Source Device
MechanismPenetrating radiation source placed/buried to silently irradiate targets over time; no explosion
Primary effectCovert cumulative dose; may go undetected until symptoms develop; targeted assassination or area denial
DetectionRequires radiation monitoring equipment; may have no visible indicator
Historical useAlexander Litvinenko (Polonium-210, 2006); Georgi Markov (radioactive pellet, 1978)
COVERT
CUMULATIVE DOSE
Radiation Particle Types & Penetration
Penetration capability determines what shielding is required. Internal contamination (inhalation, ingestion) is the primary danger for alpha and beta emitters. External exposure is the primary danger for gamma and neutron emitters.
| Type | Charge | Range in Air | Shielded By | Primary Hazard | Detection |
| Alpha (α) | Positive (+2) | 1-3 inches | Sheet of paper; skin; clothes | Internal — inhalation/ingestion; extremely damaging inside body to adjacent cells | Alpha counter at close range; not detected through most materials |
| Beta (β) | Negative (-1) | Up to 30 feet | Aluminum; plastic; heavy clothing | External (skin/eyes) and Internal; more penetrating than alpha but less organ damage per event | Geiger-Mueller detector |
| Gamma (γ) | None (photon) | Hundreds of meters | Dense materials: lead, concrete, thick earth; no defined max range | External whole-body; most dangerous external radiation; penetrates most shielding | Geiger counter; dosimeter |
| Neutron (n) | None | Thousands of feet | Hydrogenated materials: water, polyethylene, concrete | External; activates non-radioactive materials into radioactive; secondary contamination source | Specialized neutron detectors |
| X-Ray | None (photon) | Large distances | Lead; steel; concrete | External; lower energy than gamma; significant in HEMP/nuclear detonation | Dosimeter; film badge |
Gamma Radiation Halving Thickness (Alton)
Halving thickness = amount of material that reduces gamma exposure by 50%. Multiply: 2 halving thicknesses = 1/4 exposure; 3 = 1/8; 10 = 1/1024 (~0.1%). Stacking different materials multiplies protection.
| Material | Halving Thickness | 10x HVL = 1/1024 exposure | Notes |
| Lead | 0.4 in (1 cm) | 4 inches (10 cm) | Best per weight; impractical for large shelter construction |
| Steel | 1 in (2.5 cm) | 10 inches (25 cm) | Good for doors, safe room walls |
| Concrete | 2.4 in (6 cm) | 24 inches (60 cm) | Primary shelter material; basement walls provide significant protection |
| Packed Soil / Earth | 3.6 in (9 cm) | 36 inches (90 cm) | Best available material for improvised shelters; earthen berms |
| Water | 7.2 in (18 cm) | 72 inches (6 ft) | Good for supplemental shielding; water-filled containers alongside walls |
| Wood | 11 in (28 cm) | 110 inches (~9 ft) | Minimal protection alone; useful only in large mass |
THREE PRINCIPLES OF RADIATION PROTECTION (Alton, Kearny):
(1) TIME — Limit unprotected exposure; radiation absorbed is proportional to time exposed.
(2) DISTANCE — Radiation disperses over distance; double the distance, reduce exposure significantly.
(3) SHIELDING — Dense mass between you and the source reduces exposure exponentially.
Radiation Dose Thresholds & Effects
Units: 1 Gray (Gy) = 100 rads. Lethal dose (LD50/60) for humans is approximately 4-5 Gy (400-500 rads) without medical treatment. Dose rate matters as much as cumulative dose — the body can recover from low doses received slowly.
| Dose (Rad / Gy) | Syndrome | Onset | Symptoms | Survival w/o Treatment |
| <25 rad / 0.25 Gy | Subclinical | None | No symptoms; minor blood changes possible; long-term cancer risk slightly elevated | Normal |
| 75-125 rad / 0.75-1.25 Gy | Mild ARS | Hours | Mild nausea, vomiting, fatigue; resolves in days; temporary blood count reduction | ~100% |
| 200-350 rad / 2-3.5 Gy | Moderate ARS | 2-6 hrs | Nausea/vomiting, hair loss beginning ~2 wks, infection risk, bleeding tendency; latent period then illness | ~80-95% |
| 400-500 rad / 4-5 Gy | Severe ARS (LD50) | 1-2 hrs | Severe symptoms; bone marrow failure; hemorrhage; sepsis; 50% die without treatment | ~50% (LD50) |
| 600-800 rad / 6-8 Gy | Very Severe ARS | <1 hr | Profound bone marrow failure; severe GI damage; hemorrhage; sepsis; survival unlikely without advanced care | ~5-20% |
| >1000 rad / 10+ Gy | CNS Syndrome | Minutes | Immediate incapacitation; seizures; CV collapse; ataxia; death within 1-3 days | 0% |
Acute Radiation Syndrome (ARS) Signs by Phase
| Phase | Timing | Signs & Symptoms | Action |
| Prodromal (Initial) | Minutes to hours | Nausea, vomiting, diarrhea, headache, weakness, fatigue, loss of appetite; severity indicates dose received | Document onset time; seek shelter; assess dose if dosimeter available |
| Latent | Hours to weeks | Apparent recovery; patient may feel well; bone marrow being destroyed silently | Do not assume recovery; continue monitoring; maintain hydration and hygiene |
| Manifest Illness | 1-4 weeks | Hair loss; fever; infection (immune collapse); bleeding (platelet depletion); diarrhea; may be fatal | Antibiotics for infection; fluids; anti-nausea meds (Ondansetron); wound care; isolation from further exposure |
| Recovery or Death | Weeks to months | Survivors begin recovery if dose sub-lethal; partial immune reconstitution; may take 6+ months | Continued supportive care; avoid re-exposure; nutritional support |
Potassium Iodide (KI) Reference
KI PROTECTS ONLY the thyroid gland from radioactive iodine (I-131) in fallout. It does NOT protect against other radiation types. Must be taken BEFORE or within hours of exposure for maximum effect.
| Age Group | KI Dose (130mg tablet) | Timing | Duration | Notes |
| Adults >18 yrs | 130 mg (1 full tablet) | 30 min to 24 hrs prior to exposure | Once daily for 7-10 days | Highest priority: pregnant women and lactating mothers |
| Children 3-18 yrs (<150 lbs) | 65 mg (1/2 tablet) | Same | Same | Children most at risk for thyroid cancer; treat first if supply limited |
| Toddlers 1 month to 3 yrs | 32 mg (1/4 tablet) | Same | Same | Crush and mix with food/liquid |
| Infants <1 month | 16 mg (1/8 tablet) | Same | Same | Extreme care; use only if imminent exposure |
| Large dogs (>50 lbs) | 65 mg | Same | Same | Alton recommendation; not FDA-approved |
| Small dogs / cats | 32 mg | Same | Same | Crush into food |
BETADINE ALTERNATIVE (Alton): 2% Povidone-Iodine (Betadine) painted on abdomen or forearm 2-12 hours prior to exposure and re-applied daily provides some thyroid protection. Adults: 8 ml. Children 3+ (<150 lbs): 4 ml. Toddlers: 2 ml. Infants: 1 ml. Do NOT ingest Betadine. Discontinue after 3 days or when I-131 levels drop. Seafood-allergic individuals may be iodine-allergic.
RULE OF 7s (Kobler/Dutra, Kearny): For every sevenfold increase in time after detonation, radiation intensity decreases by a factor of 10. Example: Dose rate at H+1 = 1,000 r/hr; at H+7 = 100 r/hr; at H+49 = 10 r/hr; at H+343 = 1 r/hr. After 48 hours, intensity has fallen to ~1% of initial. After 2 weeks, 1/1,000th. After 14 weeks, 1/10,000th.
Fallout Radiation Decay Timeline
| Time After Detonation | Relative Radiation Level | Approximate Dose Rate (1 MT surface burst, 1 mi from center) | Shelter Action |
| H+1 hour | 100% (reference) | 1,000-10,000+ r/hr at heavy fallout zone | REMAIN SHELTERED — lethal within minutes to hours |
| H+7 hours | 10% | 100-1,000 r/hr in heavy fallout zone | REMAIN SHELTERED |
| H+24 hours (1 day) | ~2% | Still dangerous in heavy fallout zone | SHELTERED — brief forays only with dosimetry |
| H+48 hours (2 days) | ~1% | Decreasing; dependent on initial dose and local contamination | MINIMUM SHELTER PERIOD — consider exit only if necessary |
| H+2 weeks (14 days) | 0.1% | 1/1,000th of initial; generally manageable with PPE for short exposures | CAUTIOUS EGRESS POSSIBLE — field monitor required |
| H+14 weeks | 0.01% | 1/10,000th of initial | MOST SHORT-LIVED ISOTOPES DECAYED |
Fallout Plume Projections — 1-MT Surface Burst (15 mph Wind)
Source: Kobler & Dutra (2022). Based on 50% fission, 15 mph wind. Wind speed and direction are the primary variables. Check WINDFINDER.COM for local prevailing winds. Assess NUKEMAP.COM for scenario-specific estimates.
| Dose Rate Contour | Downwind Extent | Cross-Wind Width | Approximate Area | Lethality |
| 1,000 r/hr | 37 miles | 2.4 miles | 211 sq mi | Lethal within 30-60 min unsheltered |
| 100 r/hr | 104 miles | 21 miles | 2,963 sq mi | Lethal within hours to days unsheltered |
| 10 r/hr | 171 miles | 39 miles | 8,817 sq mi | Serious illness; dangerous cumulative dose over days |
| 1 r/hr | 238 miles | 58 miles | 17,765 sq mi | Elevated cancer risk over time; shelter-in-place advisable |
Critical Fallout Timelines
| Scenario | Time Window | Action Required |
| Ground burst visible / detonation confirmed | 0-15 minutes | Immediately shelter in best available structure; maximize mass overhead and on all sides |
| Fallout arrival (25 miles downwind) | ~25 minutes | Must be sheltered BEFORE fallout arrives; unsheltered at 25 min = 600 rad cumulative dose (lethal) |
| KI administration | Before or within 4 hours | Take KI immediately upon detonation confirmation; maximum effectiveness within 30 min to 24 hrs prior |
| Minimum shelter duration | 48 hours | Radiation drops to ~1% of initial after 48 hrs; remain sheltered unless evacuation mandatory |
| Optimal shelter duration | 7 days | After 7 days, most short-lived isotopes decayed; safe to conduct brief forays with dosimetry |
| Long-lived isotopes (Cs-137, Sr-90) | 30-year half-life | Persistent soil contamination; avoid ingesting local produce from contaminated zones; water testing required |
Fallout Appearance & Detection
Fallout can look like sand, fine dust, or ash — often indistinguishable from ordinary dirt. It may appear luminous at high concentrations due to radiation-induced ionization. It has no distinctive smell. The ONLY way to reliably detect it is with a radiation monitor (Geiger counter / dosimeter). A dosimeter tells you cumulative dose received; a Geiger counter gives real-time dose rate. Both are recommended for shelter kit.