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But do not forget one important rule: if such grilles close and block access to the street during a fire, then the residents of such apartments, as a rule, are trapped and have no way to get out of a burning house. Therefore, it is necessary to install at least one, and preferably several swing grilles and have an internal lock to lock them. In emergency situations, they will be in your way to free themselves. Make sure that the key for these gratings is near the window, since looking for it in case of any emergency will be a useless waste of precious seconds. Therefore, putting such lattices, think through the evacuation options in advance that you will have in case of its occurrence, otherwise you simply cannot leave a dangerous place in time.