Copy & pasted from document.
Seek immediate shelter.In the likely event that no stocked fallout shelter is available, the safest option is usually sheltering within one's own residence.If you are still outside and you haven't been able to seek shelter yet, or for some urgent reason you must go outside during plume passage, remember that a simple particulate respirator (dust mask) is an essential first line of protection against inhaling plume pulse particulates (see note in Section F-5 below.)As soon as you reach shelter, close all windows and doors to minimize inhalation of passing plume..Avoid exposure of children to contaminated surface water (puddles and rain) and ground contamination.Avoid consumption of foods contaminated with surface deposition, especially Also avoid fruits such as raspberries, which are difficult to wash and food which rapidly bioaccumulates contamination, such as mushrooms and sea vegetables. Otherwise vegetables (such as root crops, e.g. carrots, potatoes) which would not otherwise be contaminated. Use food products produced and/or packaged prior to plume passage whenever possible.Shelter livestock and pets; by staying indoors as much as possible.Cover garden sites with tarps prior to plume passage if time permits.Utilize greens grown in a greenhouse situation whenever possible.Package, box or bag contaminated clothing and footwear and remove from immediate vicinity of the living quarters if possible.Vacuum rugs, sweep floors and package or box resulting detritus as a contaminated substance and remove from immediate vicinity of living quarters if possible.Due to filtering and/or diluting all subsurface water sources and most public drinking water, sources will remain relatively safe after most types of nuclear accidents.In the days after a nuclear accident, if you have avoided inhalation of the passing plume and if you can avoid extensive exposure to ground deposition, .
Know your bioaccumulators. If you can avoid the primary ingestion pathway, including foods such as leafy green vegetables, berries, broccoli and cauliflower contaminated with surface deposition (foliar contamination,) the principle ingestion exposure pathway would likely result from contamination of the following foods which are quickly contaminated after a nuclear accident:
Remember that during and after a nuclear accident:It is safe to eat any food produced and packaged prior to the plume passage.Saltwater fish, due to the diluting effects of the ocean, accumulate much less fallout than fresh water species.Most underground and artesian water supplies will be relatively unaffected by fallout deposition.Most root vegetables, even if grown in contaminated soils, will not contain huge quantities of the most important short-lived radionuclide, 131I, which contaminates leafy green vegetables and the forage pathways immediately after a nuclear accident.Root vegetables may take up biologically available long-lived radionuclides such as 137Cs, but not in sufficient quantities to constitute an immediate health hazard.
Edit to add resource.
https://m.app.box.com/view_shared/uvqso4xgv6
Subject: If A Nuclear Bomb Explodes In A United States City, What Can & Should You Do? 
Wed Apr 16, 2014 6:54 am
