Article highlights confusion about Homeland Security safety symbols

"Safety symbols designed to instruct American citizens how to react if terrorists strike may confuse them, according to an article in the latest issue of Ergonomics in Design. For example, the symbol meaning 'Use a whistle if one is available. Shout only as a last resort' was interpreted to mean 'Yell when you hear a whistle.'

In 2002, the Department of Homeland Security (DHS) introduced a series of pictorial safety symbols designed to help prepare citizens in the wake of specific scenarios that might occur during a nuclear, chemical, or biological terrorist attack. However, in a study conducted by Christopher Mayhorn, Michael Wogalter, and Jennifer Bell of North Carolina State University, participants were unable to comprehend the meaning of many DHS safety symbols.

Based on published safety standards, the authors concluded that up to 79% of the DHS safety symbols are 'unacceptable for communicating hazard-related information.' The study, described in 'Homeland Security Safety Symbols: Are We Ready?' (Ergonomics in Design, Volume 12, Number 4, Fall 2004), details the limitations of DHS safety symbols and advocates for the inclusion of human factors methods in designing more effective safety symbols and systems. "

Wish I could find the symbols ...