Every day, millions of people wake up, go to work or school, and take part in social events. But every so often the unexpected happens: an earthquake, a fire, a chemical spill, an act of terrorism or some other disaster. Routines change drastically, and people are suddenly aware of how fragile their lives and routines can be. Each disaster can have lasting effects — people may be seriously injured or killed, and devastating and costly property damage can occur. People entering any public assembly building need to be prepared in case of an emergency.