Take cover as quickly as you can, below ground if possible, and stay there until instructed to do otherwise
Listen for official information and follow instructions
If you are caught outside and unable to get inside immediately:
Do not look at the flash or fireball; it can blind you
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
Take shelter as soon as you can, even if you are many miles away from where the attack occurred; radioactive fallout can be carried by winds for hundreds of miles
Remember the three protective factors: distance, shielding, and time.
After an Attack
Decay rates for radioactive fallout are the same for any size nuclear device. However, the amount of fallout will vary based on the size of the device and its proximity to the ground. Therefore, it might be necessary for those in areas with the highest radiation levels to 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. People in most of the affected areas could be allowed to come out of the shelter within a few days and, if necessary, evacuate to unaffected areas.
When you return to your home, you should:
Keep listening to the radio and tv for news about what to do, where to go, and places to avoid
Stay away from damaged areas and areas marked "Radiation Hazard" or "HAZMAT"
Remember that radiation can not be seen, smelled, or otherwise detected by human senses