This can help reduce the amount of potentially harmful particles you breathe. If you must be outside and cannot get inside immediately, cover your mouth and nose with a mask, cloth, or towel.If the explosion is some distance away, it could take 30 seconds or more for the blast wave to hit. Lie flat on the ground and cover your head.Take cover behind anything that might offer protection.

Do not look at the flash or fireball - it can blind you.

If you are caught outside and unable to get inside immediately: All available methods of communication will be used to provide news and / or instructions. When evacuating is in your best interest, you will be instructed to do so.In some circumstances, you may need to shelter in place for as long as one month. Expect to stay inside for at least 24 hours unless told otherwise by authorities.Radiation levels are extremely dangerous after a nuclear detonation but the levels reduce rapidly.During the time with the highest radiation levels it is safest to stay inside, sheltered away from the radioactive material outside.If possible, turn off fans, air conditioners, and forced-air heating units that bring air in from the outside.

Go as far below ground as possible or, if that is not possible, to the center of a tall building.

Find the nearest building, preferably built of brick or concrete, and go inside to avoid any radioactive material outside.

If an attack warning is issued, take cover as quickly as you can, below ground if possible, and stay there unless directed otherwise by authorities.

Listen for official information and follow the instructions provided by emergency response personnel.

Fallout 4 radiation removal