Sheltering indoors reduces radiation exposure
People should take cover indoors for the time it takes for the radioactive plume to pass. The ventilation must be turned off and the ventilation openings sealed as far as possible. Staying indoors protects people from inhaling radioactive outdoor air and reduces exposure to direct radiation from the plume.
When it is necessary to take shelter indoors, an attempt must be made to make the apartment as leak-tight as possible. The doors, windows and air vents are closed and all gaps are sealed with, for example, plastic film and tape. Ventilation must be turned off. This will reduce the amount of radioactive particles and gases entering your home.
Thick walls and ceilings attenuate radiation, so the safest place is in the middle of the building or in the basement. Avoid staying in rooms with large windows.
In general, it will be necessary to stay indoors for a few hours or 24 hours at most. Despite sealing your home, radioactive substances are certain to seep in. As soon as the radioactive plume has passed, ventilate and clean all rooms thoroughly.
Shelter indoors during a radiation hazard. Follow the instructions given by the authorities.