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Nuclear and Radiological Attack

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For Home and Work

Nuclear explosions can cause deadly effects—blinding light, intense heat (thermal radiation), initial nuclear radiation, blast, fires started by the heat pulse, and secondary fires caused by the destruction.  They also produce radioactive particles called fallout that can be carried by wind for hundreds of miles.

Terrorist use of a radiological dispersion device (RDD)—often called ”dirty nuke” or “dirty bomb”—is considered far more likely than use of a nuclear device.  These radiological weapons are a combination of conventional explosives and radioactive material designed to scatter dangerous and sub-lethal amounts of radioactive material over a general area.  Such radiological weapons appeal to terrorists because they require very little technical knowledge to build and deploy compared to that of a nuclear device.  Also, these radioactive materials, used widely in medicine, agriculture, industry and research, are much more readily available and easy to obtain compared to weapons grade uranium or plutonium.

Terrorist use of a nuclear device would probably be limited to a single smaller “suitcase” weapon.  The strength of such a weapon would be in the range of the bombs used during World War II.  The nature of the effects would be the same as a weapon delivered by an inter-continental missile, but the area and severity of the effects would be significantly more limited.

There is no way of knowing how much warning time there would be before an attack by a terrorist using a nuclear or radiological weapon.  A surprise attack remains a possibility.

The danger of a massive strategic nuclear attack on the United States involving many weapons receded with the end of the Cold War.  However, some terrorists have been supported by nations that have nuclear weapons programs.

If there were a threat of an attack from a hostile nation, people living near potential targets could be advised to evacuate or they could decide on their own to evacuate to an area not considered a likely target.  Protection from radioactive fallout would require taking shelter in an underground area, or in the middle of a large building.

In general, potential targets include:

• Strategic missile sites and military bases

• Centers of government, such as Washington, D.C. or state capitals

• Important transportation and communication centers

• Manufacturing, industrial, technology and financial centers

• Petroleum refineries, electrical power plants and chemical plants

• Major airfields and shipping ports

Taking shelter during a nuclear attack is absolutely necessary.  There are two kinds of shelters—blast and fallout.

Blast shelters offer some protection against blast pressure, initial radiation, heat and fire, but even a blast shelter could not withstand a direct hit from a nuclear detonation.

Fallout shelters do not need to be specially constructed for that purpose.  They can be any protected space, provided that the walls and roof are thick and dense enough to absorb the radiation given off by fallout particles.  The three protective factors of a fallout shelter are shielding, distance, and time.
 

• Shielding.The heavier, dense materials—thick walls, concrete, bricks, books and earth—between you and the fallout particles the better.

• Distance.  The more distance between you and the fallout particles the better.  An underground area, such as a home or office building basement, offers more protection than the first floor of a building.  A floor near the middle of a high-rise may be better, depending on what is nearby at that level on which significant fallout particles would collect.  Flat roofs collect fallout particles so the top floor is not a good choice, nor is a floor adjacent to a neighboring flat roof.

• Time.  Fallout radiation loses its intensity fairly rapidly.  In time, you will be able to leave the fallout shelter.  Radioactive fallout poses the greatest threat to people during the first two weeks, by which time it has declined to about 1% of its initial radiation level.

Remember that any protection, however temporary, is better than none at all, and the more shielding, distance and time you can take advantage of, the better.

Electromagnetic Pulse

In addition to other effects, a nuclear weapon detonated in or above the earth’s atmosphere can create an electromagnetic pulse (EMP), a high-density electrical field.  EMP acts like a stroke of lightning but is stronger, faster and briefer. EMP can seriously damage electronic devices connected to power sources or antennas.  This includes communication systems, computers, electrical appliances, and automobile or aircraft ignition systems.  The damage could range from a minor interruption to actual burnout of components.  Most electronic equipment within 1,000 miles of a high-altitude nuclear detonation could be affected.  Battery powered radios with short antennas generally would not be affected.

Although EMP is unlikely to harm most people, it could harm those with pacemakers or other implanted electronic devices. 

What to do before a nuclear or radiological attack

• Be alert and listen to your local news and radio stations.
   

• Assemble and maintain a disaster supply kit with food, water, medications, fuel and personal items adequate for up to 2 weeks—the more the better.
   

• Find out what public buildings in your community may have been designated as fallout shelters.  It may have been years ago, but start there, and learn which buildings are still in use and could be designated as shelters
  again.

• Call your local emergency management office.

• Look for yellow and black fallout shelter signs on public buildings.  Note: With the end of the Cold War, many of the signs have been removed from the buildings previously designated.

• If no noticeable or official designations have been made, make your own list of potential shelters near your home, workplace and school:  basements, or the windowless center area of middle floors in high-rise buildings, as well as subways and tunnels.

• Give your household clear instructions about where fallout shelters are located and what actions to take in case of attack.

• The City of Santa Clarita has designated all high school gymnasiums, the College of the Canyons gymnasium, the Community Center in Newhall and the Sports Complex in Canyon Country as emergency shelters.
   

• If you live in an apartment building or high-rise, talk to the manager about the safest place in the building for sheltering, and about providing for building occupants until it is safe to go out.
   

• There are few public shelters in many suburban and rural areas.  If you are considering building a fallout shelter at home, keep the following in mind:

• A basement, or any underground area, is the best place to shelter from fallout.  Often, few major changes are needed, especially if the structure has two or more stories and its basement—or one corner of it—is below ground.

• Fallout shelters can be used for storage during non-emergency periods, but only store things there that can be very quickly removed.  (When they are removed, dense, heavy items may be used to add to the shielding.)

• All the items you will need for your stay need not be stocked inside the shelter itself but can be stored elsewhere, as long as you can move them quickly to the shelter.
   

• Learn about your community’s evacuation plans.  Such plans may include evacuation routes, relocation sites, how the public will be notified and transportation options for people who do not own cars and those who have special needs.
   

What to do during a nuclear or radiological attack:

• Do not look at the flash or fireball—it can blind you
   

• If you hear an attack warning:

• Take cover as quickly as you can (if you are alone and outside, HEAD TO THE GYMNASIUM or, if you are outside with students, ESCORT YOUR STUDENTS TO THE GYMNASIUM, and stay there until instructed to do otherwise.  You must hurry.  After receiving a warning, you have very little time to find shelter.

• If you are caught outside, unable to get inside immediately, take cover behind anything that might offer protection.  Lie flat on the ground and cover your head.

• If you are inside, STAY INSIDE.  Move as far away from windows as possible and get under as much cover as possible, e.g., desks, tables, etc.  Remain in that location until you receive other instructions.

• If the explosion is some distance away, it could take 30 seconds or more for the blast wave to hit.
   

• Protect yourself from radioactive fallout.  If you are close enough to see the brilliant flash of a nuclear explosion, the fallout will arrive in about 20 minutes.  Take shelter, even if you are many miles from ground zero—radioactive fallout can be carried by the winds for hundreds of miles.  Remember the three protective factors:  shielding, distance and time.
   

• Keep a battery-powered radio with you, and listen for official information.  Follow the instructions given.  Local instructions should always take precedence:  officials on the ground know the local situation best.

 

What to do after a nuclear or radiological attack:

• Do not leave the shelter until officials say it is safe.  Follow their instructions when leaving.

• If in a fallout shelter, stay in your shelter until local authorities tell you it is permissible or advisable to leave. The length of your stay can range from a day or two to four weeks.

Contamination from a radiological dispersion device could affect a wide area, depending on the amount of conventional explosives used, the quantity of radioactive material and atmospheric conditions.

• A “suitcase” terrorist nuclear device detonated at or near ground level would produce heavy fallout from the dirt and debris sucked up into the mushroom cloud.

• A missile-delivered nuclear weapon from a hostile nation would probably cause an explosion many times more powerful than a suitcase bomb, and provide a greater cloud of radioactive fallout.

• The decay rate of the radioactive fallout would be the same, making it necessary for those in the areas with highest radiation levels to remain in shelter for up to a month.

• The heaviest fallout would be limited to the area at or downwind from the explosion, and 80% of the fallout would occur during the first 24 hours.

• Because of these facts and the very limited number of weapons terrorists could detonate, most of the country would not be affected by fallout.

• People in most of the areas that would be affected could be allowed to come out of shelter and, if necessary, evacuate to unaffected areas within a few days.
   

• Although it may be difficult, make every effort to maintain sanitary conditions in your shelter space.
   

• Water and food may be scarce.  Use them prudently but do not impose severe rationing, especially for children, the ill or elderly.
   

• Cooperate with shelter managers.  Living with many people in confined space can be difficult and unpleasant.

 

Returning to your home:

• Keep listening to the radio for news about what to do, where to go, and places to avoid.

• If your home was within the range of a bomb’s shock wave, or you live in a high-rise or other apartment building that experienced a non-nuclear explosion, check first for any sign of collapse or damage, such as:

• Toppling chimneys, falling bricks, collapsing walls, plaster falling from ceilings;

• Fallen light fixtures, pictures and mirrors;

• Broken glass from windows;

• Overturned bookcases, wall units or other fixtures;

• Fires from broken chimneys; and

• Ruptured gas and electric lines.
   

• Immediately clean up spilled medicines, drugs, flammable liquids, and other potentially hazardous materials.
   

• Listen to your battery-powered radio for instructions and information about community services.
   

• Monitor the radio and your television for information on assistance that may be provided.  Local, state and federal governments and other organizations will help meet emergency needs and help you recover from damage and losses.
   

• Broken water mains and fallen power lines may aggravate the danger at hand.
   

• If you turned gas, water and electricity off at the main valves and switch before you went to shelter:

• Do not turn the gas back on.  The gas company will turn it back on for you or you will receive other instructions.

• Turn the water back on at the main valve only after you know the water system is working and water is not contaminated.

• Turn electricity back on at the main switch only after the gas company has checked your home for gas leaks, you know the wiring is undamaged in your home and the community electrical system is functioning.

• Check to see that sewage lines are intact before using sanitary facilities.