Figure 1. Department of Homeland Security safety symbols and participant feed back data related to comprehension and critical confusion.
Safety Icon Message Content % Correct
Comprehension		 % Critical
Confusion		 # Participant Design
Suggestions
someone under some rumble with a flash light Tap on pipe or on wall so that rescuers can hear you. 7.0% 0.0% 34
someone is whistling Use a whistle if one is available. Shout only as a last resort – shouting can cause a person to inhale dangerous amounts of dust. 12.3% 86.0% 24
someone leaning up agaist a door If the door is not hot, brace yourself against the door and slowly open it. 15.8% 64.9% 26
someone at a chemical spill If you see signs of a chemical attack, try to define the impact area or where the chemical is coming from. 33.3% 21.1% 27
don't move a lot if trapped under rumble Avoid unnecessary movement so that you don’t kick up dust. 42.1% 15.8% 24
test a door with back side of hand Use the back of your hand to feel the lower, middle, and upper parts of closed doors. 45.6% 31.6% 27
clocks, computer, tv, and a boom box In the event of a biological attack, public health officials may not be immediately be able to provide information on what you should do. However, you should watch TV, or check the Internet for official news as it becomes available. 47.4% 35.1% 31
sick or dead animals can cause problems Many sick or dead birds, fish or small animals are also cause for suspicion. 47.4% 40.4% 26
don't run when on fire If you catch fire do not run. 59.6% 28.1% 15
get medical attention as soon as possible Seek emergency medical attention. 63.2% 5.3% 11
use a flash light if trapped If possible use a flash light to signal your location. 63.2% 7.0% 10
reduce exposure to reduce risk Time: Minimizing time spent exposed will also reduce your risk. 63.2% 15.8% 24