No one knows for sure when a fire will happen, so it is (extreme) necessary to make preparations before a fire starts. Check the fire escape in advance and make sure that you can find in the dark when lights have failed. Find out the nearest fire extinguisher(灭火器) is and read the instructions to learn how (use) it.
Don't lose your head when a fire breaks out. First, telephone the fire department immediately when fire just gets started. Take care not to be overcome by smoke, can kill you quickly. Cover your mouth a wet towel or cloth, and avoid getting into the smoke. Don't get in an elevator, as you may get trapped if the electricity (fail). If you can not get away yourself, it is of great importance to hang something out of the window to attract attention as a sign of asking for help.
In short, if you make preparations before hand and take precautions(预防措施) during the fire, chances are that will survive in case of a fire if it really breaks out some day.
