Are trips for water or to restrooms going to increase radiation exposure?
The RM should note where drinking fountains, water outlets, and restrooms are located throughout the bomb shelter. After fallout has arrived, he or she should check the radiation levels at these locations. Some of them may have to be blocked off until the radiation decays to a safer level.
In nearly all public fallout bomb shelters, there will be plenty of water for drinking, cooking, and flushing toilets as long as there are no nuclear detonations close enough to break water lines, damage storage tanks, or cause an electric power failure.
Remember, water arrives on pressure through gravity fed pipes in most places (the water tower on the hill in your part of town, for example).
If the electric power is knocked out by a distant nuclear explosion, there will still be water in the pipes and tanks, which flow by gravity. Water should be used as needed for drinking and sparingly for other purposes throughout the emergency.
In a nuclear war there is a possibility that the water supply might fail, so water should be stored in the bomb shelter before fallout arrives. If the bomb shelter runs out of water in a heavy fallout area, the RM may be faced with some difficult decisions and unpleasant situations.
About two weeks’ supply of water should be stored in areas where heavy fallout is expected. About two weeks after fallout has arrived, the radiation intensity even in the worst places will decay to levels where people can make emergency trips without the risk of radiation sickness or death.
In areas where heavy fallout is expected and in the case of hot, crowded conditions in the fallout bomb shelters, a minimum of about seven gallons of water should be stored per person, just for drinking.