National Security Emergencies
In addition to the natural and technological hazards described in this publication, Americans face threats posed by hostile governments or extremist groups. These threats to national security include acts of terrorism and acts of war.
The following is general information about national security emergencies. For more information about how to prepare for them, including volunteering in a Citizen Corps program, see the "For More Information" chapter at the end of this guide.
Terrorism is the use of force or violence against persons or property in violation of the criminal laws of the United States for purposes of intimidation, coercion or ransom. Terrorists often use threats to create fear among the public, to try to convince citizens that their government is powerless to prevent terrorism, and to get immediate publicity for their causes.
Acts of terrorism range from threats of terrorism, assassinations, kidnappings, hijackings, bomb scares and bombings, cyber attacks (computer-based), to the use of chemical, biological and nuclear weapons.
High-risk targets include military and civilian government facilities, international airports, large cities and high-profile landmarks. Terrorists might also target large public gatherings, water and food supplies, utilities, and corporate centers. Further, they are capable of spreading fear by sending explosives or chemical and biological agents through the mail.
In the immediate area of a terrorist event, you would need to rely on police, fire and other officials for instructions. However, you can prepare in much the same way you would prepare for other crisis events.
Preparing for Terrorism
- Wherever you are, be aware of your surroundings. The very nature of terrorism suggests there may be little or no warning.
- Take precautions when traveling. Be aware of conspicuous or unusual behavior. Do not accept packages from strangers. Do not leave luggage unattended. Unusual behavior, suspicious packages and strange devices should be promptly reported to the police or security personnel.
- Do not be afraid to move or leave if you feel uncomfortable or if something does not seem right.
- Learn where emergency exits are located in buildings you frequent. Notice where exits are when you enter unfamiliar buildings. Plan how to get out of a building, subway or congested public area or traffic. Note where staircases are located. Notice heavy or breakable objects that could move, fall or break in an explosion.
- Assemble a disaster supply kit at home and learn first aid. Separate the supplies you would take if you had to evacuate quickly, and put them in a backpack or container, ready to go.
- Be familiar with different types of fire extinguishers and how to locate them. Know the location and availability of hard hats in buildings in which you spend a lot of time.
Protection Against Cyber Attacks
Cyber attacks target computer or telecommunication networks of critical infrastructures such as power systems, traffic control systems, or financial systems. Cyber attacks target information technologies (IT) in three different ways. First, is a direct attack against an information system "through the wires" alone (hacking). Second, the attack can be a physical assault against a critical IT element. Third, the attack can be from the inside as a result of compromising a trusted party with access to the system.
- Be prepared to do without services you normally depend on that could be disrupted-electricity, telephone, natural gas, gasoline pumps, cash registers, ATM machines, and internet transactions.
- Be prepared to respond to official instructions if a cyber attack triggers other hazards, for example, general evacuation, evacuation to shelter, or shelter-in-place, because of hazardous materials releases, nuclear power plant incident, dam or flood control system failures.
Preparing for a Building Explosion
Explosions can collapse buildings and cause fires. People who live or work in a multi-level building can do the following:
- Review emergency evacuation procedures. Know where emergency exits are located.
- Keep fire extinguishers in working order. Know where they are located, and learn how to use them.
- Learn first aid. Contact the local chapter of the American Red Cross for information and training.
- Building owners should keep the following items in a designated place on each floor of the building:
- Portable, battery-operated radio and extra batteries
- Several flashlights and extra batteries
- First aid kit and manual
- Several hard hats
- Fluorescent tape to rope off dangerous areas
If you receive a bomb threat, get as much information from the caller as possible. Keep the caller on the line and record everything that is said. Then notify the police and the building management.
If you are notified of a bomb threat, do not touch any suspicious packages. Clear the area around suspicious packages and notify the police immediately. In evacuating a building, don't stand in front of windows, glass doors or other potentially hazardous areas. Do not block sidewalk or streets to be used by emergency officials or others still exiting the building.
Suspicious Parcels and Letters
Be wary of suspicious packages and letters. They can contain explosives, chemical or biological agents. Be particularly cautious at your place of employment.
Some typical characteristics postal inspectors have detected over the years, which ought to trigger suspicion, include parcels that-
With suspicious envelopes and packages other than those that might contain explosives, take these additional steps against possible biological and chemical agents:
- Are unexpected or from someone unfamiliar to you.
- Have no return address, or have one that can't be verified as legitimate.
- Are marked with restrictive endorsements, such as "Personal," "Confidential" or "Do not x-ray."
- Have protruding wires or aluminum foil, strange odors or stains.
- Show a city or state in the postmark that doesn't match the returnaddress.
- Are of unusual weight, given their size, or are lopsided or oddly shaped.
- Are marked with any threatening language.
- Have inappropriate or unusual labeling.
- Have excessive postage or excessive packaging material such as masking tape and string.
- Are addressed to someone no longer with your organization or are otherwise outdated.
- Have incorrect titles or title without a name.
- Are not addressed to a specific person.
- Have handwritten or poorly typed addresses.
- Have incorrect titles or title without a name.
- Refrain from eating or drinking in a designated mail handling area.
- Place suspicious envelopes or packages in a plastic bag or some other type of container to prevent leakage of contents.
- Never sniff or smell suspect mail.
- If you do not have a container, then cover the envelope or package with anything available (e.g., clothing, paper, trash can, etc.) and do not remove the cover.
- Leave the room and close the door, or section off the area to prevent others from entering.
- Wash your hands with soap and water to prevent spreading any powder to your face.
- If you are at work, report the incident to your building security official or an available supervisor, who should notify police and other authorities without delay.
- List all people who were in the room or area when this suspicious letter or package was recognized. Give a copy of this list to both the local public health authorities and law enforcement officials for follow-up investigations and advice.
- If you are at home, report the incident to local police.
- Have handwritten or poorly typed addresses.
What To Do if There is an Explosion
Leave the building as quickly as possible. Do not stop to retrieve personal possessions or make phone calls. If things are falling around you, get under a sturdy table or desk until they stop falling. Then leave quickly, watching for weakened floors and stairs and falling debris as you exit.
- If there is a fire:
- Stay low to the floor and exit the building as quickly as possible.
- Cover your nose and mouth with a wet cloth.
- When approaching a closed door, use the back of your hand to feel the lower, middle and upper parts of the door. Never use the palm of your hand or fingers to test for heat: burning those areas could impair your ability to escape a fire (i.e., ladders and crawling).
- If the door is NOT hot, open slowly and ensure fire and/or smoke is not blocking your escape route. If your escape route is blocked, shut the door immediately and use an alternate escape route, such as a window. If clear, leave immediately through the door. Be prepared to crawl. Smoke and heat rise. The air is clearer and cooler near the floor.
- If the door is hot, do not open it. Escape through a window. If you cannot escape, hang a white or light-colored sheet outside the window, alerting fire fighters to your presence.
- Heavy smoke and poisonous gases collect first along the ceiling. Stay below the smoke at all times.
- If you are trapped in debris:
- Do not light a match.
- Do not move about or kick up dust. Cover your mouth with a handkerchief or clothing.
- Rhythmically tap on a pipe or wall so that rescuers can hear where you are. Use a whistle if one is available. Shout only as a last resort when you hear sounds and think someone will hear you-shouting can cause a person to inhale dangerous amounts of dust.
Chemical and Biological Weapons
In case of a chemical or biological weapon attack near you, authorities will instruct you on the best course of action. This may be to evacuate the area immediately, to seek shelter at a designated location, or to take immediate shelter where you are and seal the premises. The best way to protect yourself is to take emergency preparedness measures ahead of time and to get medical attention as soon as possible, if needed.
Chemical warfare agents are poisonous vapors, aerosols, liquids or solids that have toxic effects on people, animals or plants. They can be released by bombs, sprayed from aircraft, boats, or vehicles, or used as a liquid to create a hazard to people and the environment. Some chemical agents may be odorless and tasteless. They can have an immediate effect (a few seconds to a few minutes) or a delayed effect (several hours to several days). While potentially lethal, chemical agents are difficult to deliver in lethal concentrations. Outdoors, the agents often dissipate rapidly. Chemical agents are also difficult to produce.
There are six types of agents:
- Lung-damaging (pulmonary) agents such as phosgene,
- Vesicants or blister agents such as mustard,
- Nerve agents such as GA (tabun), GB (sarin), GD (soman), GF, and VX,
- Incapacitating agents such as BZ, and
- Riot-control agents (similar to MACE).
Biological agents are organisms or toxins that can kill or incapacitate people, livestock and crops. The three basic groups of biological agents which would likely be used as weapons are bacteria, viruses, and toxins.
Most biological agents are difficult to grow and maintain. Many break down quickly when exposed to sunlight and other environmental factors, while others such as anthrax spores are very long lived. They can be dispersed by spraying them in the air, or infecting animals which carry the disease to humans as well through food and water contamination.
- Bacteria. Bacteria are small free-living organisms that reproduce by simple division and are easy to grow. The diseases they produce often respond to treatment with antibiotics.
- Viruses. Viruses are organisms which require living cells in which to reproduce and are intimately dependent upon the body they infect. Viruses produce diseases which generally do not respond to antibiotics. However, antiviral drugs are sometimes effective.
- Toxins. Toxins are poisonous substances found in, and extracted from, living plants, animals, or microorganisms; some toxins can be produced or altered by chemical means. Some toxins can be treated with specific antitoxins and selected drugs.
Anthrax spores formulated as a white powder were mailed to individuals in the government and media in the fall of 2001. Postal sorting machines and the opening of letters dispersed the spores as aerosols. Several deaths resulted. The effect was to disrupt mail service and to cause a widespread fear of handling delivered mail among the public.
- Aerosols-Biological agents are dispersed into the air, forming a fine mist that may drift for miles. Inhaling the agent may cause disease in people or animals.
- Animals-Some diseases are spread by insects and animals, such as fleas, mice, flies, and mosquitoes. Deliberately spreading diseases through livestock is also referred to as agroterrorism.
- Food and water contamination-Some pathogenic organisms and toxins may persist in food and water supplies. Most microbes can be killed, and toxins deactivated, by cooking food and boiling water.
Person-to-person spread of a few infectious agents is also possible. Humans have been the source of infection for smallpox, plague, and the Lassa viruses.
What to Do to Prepare for a Chemical or Biological Attack
Assemble a disaster supply kit (see the "Emergency Planning and Disaster Supplies" chapter for more information) and be sure to include:
- Battery-powered commercial radio with extra batteries.
- Non-perishable food and drinking water.
- Roll of duct tape and scissors.
- Plastic for doors, windows and vents for the room in which you will shelter in place-this should be an internal room where you can block out air that may contain hazardous chemical or biological agents. To save critical time during an emergency, sheeting should be pre-measured and cut for each opening.
- First aid kit.
- Sanitation supplies including soap, water and bleach.
What to Do During a Chemical or Biological Attack
- Listen to your radio for instructions from authorities such as whether to remain inside or to evacuate.
- If you are instructed to remain in your home, the building where you are, or other shelter during a chemical or biological attack:
- Turn off all ventilation, including furnaces, air conditioners, vents and fans.
- Seek shelter in an internal room, preferably one without windows. Seal the room with duct tape and plastic sheeting. Ten square feet of floor space per person will provide sufficient air to prevent carbon dioxide build-up for up to five hours. (See "Shelter" chapter.)
- Remain in protected areas where toxic vapors are reduced or eliminated, and be sure to take your battery-operated radio with you.
- If you are caught in an unprotected area, you should:
- Attempt to get up-wind of the contaminated area.
- Attempt to find shelter as quickly as possible.
- Listen to your radio for official instructions.
What to Do After a Chemical Attack
Immediate symptoms of exposure to chemical agents may include blurred vision, eye irritation, difficulty breathing and nausea. A person affected by a chemical or biological agent requires immediate attention by professional medical personnel. If medical help is not immediately available, decontaminate yourself and assist in decontaminating others. Decontamination is needed within minutes of exposure to minimize health consequences. (However, you should not leave the safety of a shelter to go outdoors to help others until authorities announce it is safe to do so.)
Use extreme caution when helping others who have been exposed to chemical agents:
- Remove all clothing and other items in contact with the body. Contaminated clothing normally removed over the head should be cut off to avoid contact with the eyes, nose, and mouth. Put into a plastic bag if possible. Decontaminate hands using soap and water. Remove eyeglasses or contact lenses. Put glasses in a pan of household bleach to decontaminate.
- Remove all items in contact with the body.
- Flush eyes with lots of water.
- Gently wash face and hair with soap and water; then thoroughly rinse with water.
- Decontaminate other body areas likely to have been contaminated. Blot (do not swab or scrape) with a cloth soaked in soapy water and rinse with clear water.
- Change into uncontaminated clothes. Clothing stored in drawers or closets is likely to be uncontaminated.
- If possible, proceed to a medical facility for screening.
What to Do After a Biological Attack
In many biological attacks, people will not know they have been exposed to an agent. In such situations, the first evidence of an attack may be when you notice symptoms of the disease caused by an agent exposure, and you should seek immediate medical attention for treatment.
In some situations, like the anthrax letters sent in 2001, people may be alerted to a potential exposure. If this is the case, pay close attention to all official warnings and instructions on how to proceed. The delivery of medical services for a biological event may be handled differently to respond to increased demand. Again, it will be important for you to pay attention to official instructions via radio, television, and emergency alert systems.
If your skin or clothing comes in contact with a visible, potentially infectious substance, you should remove and bag your clothes and personal items and wash yourself with warm soapy water immediately. Put on clean clothes and seek medical assistance. For more information, visit the website for the Centers for Disease Control and Prevention, http://www.bt.cdc.gov/.
Nuclear and Radiological Attack
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 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:
Taking shelter during a nuclear attack is absolutely necessary. There are two kinds of shelters-blast and fallout.
- Strategic missile sites and military bases.
- Centers of government such as Washington, D.C., and state capitals.
- Important transportation and communication centers.
- Manufacturing, industrial, technology and financial centers.
- Petroleum refineries, electrical power plants and chemical plants.
- Major ports and airfields.
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.
The more heavy, dense materials-thick walls, concrete, bricks, books and earth-between you and the fallout particles, the better.
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.
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.
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 include 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
- Learn the warning signals and all sources of warning used in your community. Make sure you know what the signals are, what they mean, how they will be used, and what you should do if you hear them.
- 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. (See the "Emergency Planning and Disaster Supplies" chapter for more information).
- 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.
- 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.)
- See the "Tornadoes" section in the "Thunderstorms" chapter for information on the "Wind Safe Room," which could be used as shelter in the event of a nuclear detonation or for fallout protection, especially in a home without a basement.
- 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. See the "Evacuation" chapter for more information.
- Acquire other emergency preparedness booklets that you may need. See the "For More Information" chapter at the end of this guide.
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, BELOW GROUND IF POSSIBLE, and stay there unless instructed to do otherwise.
- 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 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
In a public or home shelter:
- 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.
- IA "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
For more information relevant to terrorism consult the following chapters:
- 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.
- 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.
- The danger may be aggravated by broken water mains and fallen power lines.
- 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 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.
- Stay away from damaged areas.
- Stay away from areas marked "radiation hazard" or "HAZMAT."
- The "Earthquakes" chapter for information about protecting yourself when a building is shaking or unsafe and the Fire chapter for tips on fire safety.
- The "Hazardous Materials Incidents" chapter for information about sealing a home.
- The "Emergency Planning and Disaster Supplies" chapter for information about preparing a disaster supply kit.
- The "Shelter" chapter for measures regarding water purification.
- The "Evacuation" chapter for information about evacuation procedures.
- The "Recovering from Disaster" chapter for information about crisis counseling.
Homeland Security Advisory System
The Homeland Security Advisory System was designed to provide a comprehensive means to disseminate information regarding the risk of terrorist acts to federal, state, and local authorities and to the American people. This system provides warnings in the form of a set of graduated "Threat Conditions" that increase as the risk of the threat increases. At each threat condition, federal departments and agencies would implement a corresponding set of "Protective Measures" to further reduce vulnerability or increase response capability during a period of heightened alert.
Although the Homeland Security Advisory System is binding on the executive branch, it is voluntary to other levels of government and the private sector. There are five threat conditions, each identified by a description and corresponding color.
The greater the risk of a terrorist attack, the higher the threat condition. Risk includes both the probability of an attack occurring and its potential gravity.
Threat conditions are assigned by the Attorney General in consultation with the Assistant to the President for Homeland Security. Threat conditions may be assigned for the entire nation, or they may be set for a particular geographic area or industrial sector. Assigned threat conditions will be reviewed at regular intervals to determine whether adjustments are warranted.
Threat Conditions and Associated Protective Measures
There is always a risk of a terrorist threat. Each threat condition assigns a level of alert appropriate to the increasing risk of terrorist attacks. Beneath each threat condition are some suggested protective measures that the government and the public can take, recognizing that the heads of federal departments and agencies are responsible for developing and implementing appropriate agency-specific Protective Measures.
For detailed information on Protective Measures, please visit our Threat Status Explained page.