Being aware of your surroundings is an easy way to make sure you and your family are prepared. Children especially are easily disoriented and can be frightened in an emergency situation, by making sure they know where the exits are and where to meet you if they get lost we can lessen the potential stress for them, while keeping them safer. If it's a family habit to do this it becomes second nature instead of a scarier thing.
I loved this tip from Dianna, although we've never had to evacuate a building I have had kids wander off and it was NOT fun for either of us. Taking a few minutes to plan a meeting place and making sure they always know who to ask for help would have probably saved me a few gray hairs.