A 10 kiloton Nuclear Weapon Attack: Consequences and Response Challenges

1. A 10 kiloton Nuclear Weapon Attack: Consequences and Response Challenges Victor E. Anderson, C.H.P. Radiologic Health Branch California Public Health Department

3. Some Thoughts • How big – kilotons • What will it do? • How far? • How many?

4. Effects • Intense nuclear reaction lasting for tens to hundreds of microseconds. • Fireball formation • Light in the form of visible light, heat, and high energy photons (x and gamma rays). • Neutron Radiation • Electro-magnetic Pulse (EMP) • Shock or concussion wave. • Radioactive materials leading to fallout.

5. The Fireball • Temperature starts at millions of degrees centigrade and falls to about 3,000 degrees centigrade at the maximum radius. • Size varies with strength. • R ≈ 145 (kt)0.4 for contact surface. • R ≈ 110 (kt)0.4 for air burst. • R ≈ 90 (kt)0.4 for surface burst.

6. Immediate Ionizing Radiation Effects • Large burst of X, Gamma, and Neutron radiation is given off during the explosion. • A prompt dose of 1,000 rad for unprotected persons may occur out to 0.75 miles from the explosion center. • A prompt dose of 300 rad for unprotected persons may occur out to 0.88 miles from the explosion center. • “Natural” shields such as hills, concrete structures, etc. can provide some protection.

7. Shock Wave • The explosion will create a “wall” of compressed air that expands outward. • This creates the blast or concessive effects. • Damage is highly dependent on height of burst. • Air or Ground

8. Shock Wave • Ground Burst • Wave moves up and along the ground. • Broken up by terrain features. • Hills • Valleys • Buildings • Less efficient in causing damage.

9. Shock Wave • Difficult to predict Destructive Effects • Rough Guides • Generally an over pressure of ~ 5 - 10 psi will severely damage most structures. • 10 kt airburst should severely damage all structures out to about 1 mile from the explosion’s center (ground zero). • Severe damage distance from a ground burst is strongly dictated by terrain features.

10. Shock Wave Damage • Fragments • Secondary fires • Explosions from gas tanks • Damage to vehicles and aircraft.

11. Fallout • Probably the most dangerous effect from a nuclear weapon. • The amount depends on size and type of burst. • Ground burst yields the largest amount. • Air burst yields the lowest. • Weapon can be surrounded with Cobalt or other materials to enhance fallout.

12. ~ 27,000 ft ~ 1.6 miles

13. Fallout • Spread and extent is highly dependent on weather conditions. • Individuals may be killed from radiation exposure. • Arrival time depends on wind speed.

14. Fallout • Composed of fission fragments, activation products, and unused nuclear fuel. • Initially decays off very rapidly. A(t) = Aot-1.2 • Time = t • A(t) = activity after a period of time (t) • Ao = equal activity at start.

16. First Hour

17. First Six Hours

18. First 24 Hours

19. Putting It Altogether 100 % Deaths ~ EMP Limit ~ 50% 3rd Degree Burns

20. Response Challenges • Major event • Potential loss of majority of elected officials. • Initial confusion and chaos. • Response organization operations. • Approximately 100,000 or more injured. • Infrastructure Damage. • Fallout.

21. Continuity of Government Operations • A real bad day • Maximum loss of life. • Entire upper elected officials dead. • Evacuation decisions may fall to a much lower ranked official. • Head of the EOC. • COGO is a vital part of a nuclear weapons attack response plan.

22. Response Operations • Chaos and confusion. • Communications gone. • Normal methods of organizing Incident Command structures will be challenged. • Individual fire stations and precinct stations may be isolated. • ICS/SEMS PRINCPLES.

23. Work Areas • Emergency Zone • Areas where workers can maintain doses less than or equal to 5 rem per year. (State radiation worker limits). • 25 rem limit for non-life saving operations deemed vital to the response. • Contamination control may require level A or equivalent PPE. • Search and Rescue will be difficult. • Life Saving Zone • Entry only to save lives. • Doses must be less than 100 rem per entry. • Lethal Zone • No Entry • Dose Rates are too high.

24. Work Zones • Zones will shrink as fallout decays. • Controlling rescue worker’s dose is a must. • Survivors who have greater than 1,000 rad are dead. • Organization will be the key to survival. • ICS/SEMS

25. Fallout Injuries • Subject to factors of evacuation and time in area. • For a 10 kt ground burst, potentially 60,000 deaths. • Fatal Levels will arrive quickly depending on the wind speed and other meteorological conditions.

27. Evacuation Challenges • TIME!!!! • A delay of one hour post denotation can mean 10 to 15 thousand dead from radiation syndrome. • Thousands more with serious radiation sickness. • Evacuation plan is vital to saving thousands.

28. Evacuation Challenges • Where is the fallout? • Real fallout patterns vary with wind shear. • High areas may “skip.” • How do you get the word out? • Dust, smoke and confusion closer to “Ground Zero.”

29. Fallout Shelters • Remember dose rate is a function of t-1.2. • Thus integrated dose: • Where: Ti = the start time (not zero) and Tf = the finish time; and R = the dose rate (R/hr) at Ti. Time is in hours. • Start out in 1,000 rad/hr field and stay one hour you get about 650 rad of dose.

30. Fallout Shelters • Dose for staying and leaving should be well under 100 rad. • How much? • Attenuation Factors • Glasstone lists many. • Building practices have changed.

31. Fallout SheltersThings to See and Do • What are the realistic attenuation factors for underground parking and sub-floors of large buildings, and so forth? • Stocks of food, water, and other supplies? • How long? • Dose for sheltering in upper stories. • ?????, etc.

32. Ingestion Pathway • Fallout can and will extend for a long ways. • Currently our best assessments for radioactivity limits in food are via the EPA PAG manual. • Clearly hundreds of square miles of agricultural land will affected. • Economic affect will be huge. • Need to reassess from a technical perspective what is allowable/not allowable.

33. Ingestion Pathway • Environmental Monitoring • Who eats what? And how much? • Effects of sequestering food stuffs? • Export market • Local availability of food. • Resupply?

34. Miscellaneous Stuff • Flash Blindness • Secondary damage – fires and such. • Medical Surge • Refugee Housing

35. Summary • The single nuclear weapon attack scenario needs closer scrutiny. • Response planning will require much thought and analysis. • Recovery is also important.

37. Hiroshima Today. Ground Zero is near the Center of the Picture

38. Concluding Remarks • With correct planning and training a good response can happen. • Clear objectives, good equipment, and a well led and organized response organization can prevail.