The DEFCON Warning System

Ongoing Geointel and Analysis in the theater of nuclear war. Established 1984

Alert Levels

DEFCON Warning System

The following are the recommended steps to take for each of the different DEFCON Warning System Alert Levels. The pubic is advised that these are only recommendations and that each individual must determine for themselves what they should do at a particular time.



Section 1: Alert Level and Updates

This is the standard peacetime alert level. All is quiet. There are no known imminent nuclear threats. Updates will be given the 1st of every month (except for April 1st or if the day falls on a Saturday, in which case the update will appear a day later) with immediate updates issued as the situation warrants.

Section 2: Building a Fallout Shelter

The public should utilise this time to plan and build a fallout shelter. It is best to do this during peace where there is no time pressure. Instead of having to build an Expedient shelter which provides only minimal and cramped protection, one planned for and built now has the potential to offer far more protection under much more comfortable conditions.
  1. Remember, it will take 17.5 inches of packed earth to provide a Protection Factor (PF) of 32.
  2. The minimum PF for government fallout shelters is 40, which is considered grossly inadequate.
  3. It is highly recommended to obtain a PF of at least 1000.
  4. For every 3.5 inches of packed earth added, the Protection Factor doubles.
  5. To achieve a PF of 1024, you will need 35 inches of packed earth. The more packed earth you add, the higher your Protection Factor.
  6. For those who live downwind of major or multiple targets (or anyone who lives east of the Rockies), a PF of 10000 is the absolute minimum you should strive for.
  7. That’s 49 inches of packed earth, only 14 inches more than a PF of 1000.

Section 3: Stocking up on Supplies

Now is also an excellent time to begin stocking up on non-perishable items. Each time you go to the grocery store, pick up one or two additional items and store them.
  1. Consider items like bathroom tissue, paper towels, trash bags, toothbrushes, cat litter, plastic wrap, empty plastic bottles (for water), and other non-perishable items you may need personally.
  2. Make sure the stocked items won’t go bad over the years.
  3. Think about clothing and blankets as well. Visiting your local Thrift Store will allow you to stock up on essential items without spending much. Don’t let your pride get in the way. After a nuclear war, you won’t care what you’re wearing.

Section 4: Recommended Reading

This is also a good time to read the handbook “Nuclear War Survival Skills” by Cresson H. Kearny. You can find it on our site: Cresson H. Kearny’s “Nuclear War Survival Skills”


Section 1: Alert Level and Updates

This is the non-standard peacetime alert level. All is quiet, though there have been some events which warrant observation. There are no known imminent nuclear threats. More likely than not, nothing will happen and the DEFCON level will eventually revert back to Green. Updates will be given every three weeks with immediate updates issued as the situation warrants.

Section 2: Maintaining Normal Activity

Generally speaking, there is no need to alter activity from Level Green. The DEFCON Warning System is designed to be sensitive to certain situations, and has gone to Blue several times in the past and reverted back to Green a few weeks later. This is normal and nothing to be concerned about.

Section 3: Stocking up on Supplies and Fallout Shelter

Continue to stock up on non-perishable supplies and building your fallout shelter.


Section 1: Alert Level and Updates

Events of concern are occurring in the world theatre. There are no known immediate nuclear threats, however the situation is considered fluid. Updates will be given every seven days with immediate updates issued as the situation warrants.

Section 2: Uncertainty and Decision-making

This is the most uncertain of the Alert levels. You must make a decision every day (or sometimes every hour) as to whether you think the situation will resolve itself or get out of hand. To be on the realistic side, you should hope for the best but plan for the worst.

Section 3: The Role of DEFCON Warning System

Like Blue, the world has gone to this level several times and marched back. The DEFCON Warning System is a barometer, not a prognosticator. You must decide for yourself what to do with information you have.

Section 4: Evacuation and Fallout Shelter

At this level, it is recommended that if you live in a city or near another target, you begin to make evacuation plans to a safer area.
  1. Be sure you have family there who will take you in and can have an appropriate fallout shelter and supplies for you. (Generally, you should bring your own supplies and not rely on others.)
  2. If the crisis worsens, you may wish to evacuate before the Alert level rises to the next stage.
  3. If you have not already done so, now is the time to begin building a fallout shelter. Use plans for an Expedient shelter and, if there is time later, you can expand upon them.

Section 5: Gathering Supplies and Preparation

Begin gathering fuel supplies, keeping them separate from your shelter.
  1. Ensure your weapons are clean and serviceable; obtain them if you don’t have any and learn how to use them.
  2. Gather supplies of food with long shelf-life (cereals, flour, rice, dehydrated foods), vitamins, medicines, and other necessary items.
  3. Obtain enough dry food for pets to last an indefinite period.
  4. Plan for at least two years of self-sufficiency; consider gathering seed supplies for farming if you have land. Wheat and honey provide essential nutrients and are cost-effective options.
  5. Remember to include supplements to compensate for any dietary deficiencies.

Section 6: Financial Considerations and Shopping

When buying supplies, especially on the higher Alert levels, consider placing your purchases on a credit card. If WWIII breaks out, who is going to come and collect?

Section 7: Benefits of Preparedness

Remember, if nothing happens, you will be able to use all these things anyway, so nothing will actually go to waste. You’ll just have done your grocery shopping early and gotten it out of the way!


Section 1: Alert Level and Updates

Hostilities have or are about to break out. There is the possibility of a nuclear strike. Updates will be given every day with immediate updates issued as the situation warrants.

Section 2: Evacuation Considerations

If you live in a targeted city with a population of 100,000 or more or you are near another target area and you do not have a blast shelter (different than a fallout shelter…likely you will not have a blast shelter) then consider evacuation.

Section 3: Stocking up on Supplies and Finances

Check your inventory. Anything you lack in food or supplies you should make up for now. Get as much as you can. Make several trips if you have to. Remember, put it on the credit card. If you have a bank account, close it and hold all the cash in your shelter or other safe place.

Section 4: Building an Expedient Shelter

If you do not have a shelter, then you must begin making an Expedient shelter now.
  1. Two people can make a 6 person Expedient shelter that is 3-1/2 feet wide, 4-1/2 feet high, and 16-1/2 feet long in less than 48 hours. (In this particular timed experiment, a father and son took 36 hours to build their shelter near the edge of a cornfield. The ground was not hard but was not tilled, either. Your results will, of course, vary.)


Section 1: Alert Level and Updates

A nuclear attack is in progress or is considered to be highly likely. It is planned for the Alert level to go to Red before an actual attack. This will introduce a possibility of error, but will also give the most warning. You must decide for yourself whether to act upon it or not.
  1. Updates will be given at 7 A.M and 7 P.M Pacific Time with immediate updates issued as the situation warrants. Post-attack, radiation levels will be given if possible.
  2. Updates for radiation will also be given at 8 A.M. and 8 P.M. Pacific Time. Immediate updates will be issued as the situation warrants.

Section 2: Building a Fallout Shelter

For those in an attack area, if you do not have a fallout shelter, you must begin making one immediately. Do not travel far from your shelter. If you are in a city or near another nuclear target, you may not have time to evacuate and it may no longer be possible due to jammed roadways or travel restrictions.

Section 3: Water Preparation

Fill all plastic bottles with water. Fill your bathtub and sinks with water as well. If you can fill it with water, do so. You can never have too much water. Repeat: You can never have too much water! Remember that the water in your hot water tank is also another source of clean water.

Section 4: Gathering Supplies and Power Disconnect

If there is anything you need in your shelter that you do not have there already, move it there. Disconnect all power sources to prevent damage from any EMP. (Note that the EMP effect is only theoretical.) Keep your family together during the crisis.

Section 5: Supply Run (Note: Not Recommended)

If you have no supplies and the Alert level has just changed, then you may decide to take a (enormous) risk and do a desperate supply run. There is a chance that you may still have time. Likely, however, a panicked public has already taken all the supplies. Note that we do not recommend this course of action, but a fallout shelter with no supplies is not a fallout shelter but a tomb.

Ongoing Geointel and Analysis in the theater of nuclear war.

© 2023 The DEFCON Warning System. Established 1984.

The DEFCON Warning System is a private intelligence organization which has monitored and assessed nuclear threats by national entities since 1984. It is not affiliated with any government agency and does not represent the alert status of any military branch. The public should make their own evaluations and not rely on the DEFCON Warning System for any strategic planning. At all times, citizens are urged to learn what steps to take in the event of a nuclear attack.