a sign for shelter

acts against air alarm also arms attack authority basement bombing bombs building buildingtechnically cellar civil combatants crisis danger designed different disaster europe evacuation example exists fall falls fire gas gasattack independent injuries local make material munitions nuclear part people plate premises preparedness protect protected protection reinforced room rsv sanctuary scandinavia security shelter shelters sign skyddsrum space srsa station stations subway sure sweden swedish symbol terror terrorist threat tunnel tunnels types usually war wmd world