Mr. Angry was developed to warn everyone regardless of language, culture, age, education, that something extremely dangerous was waiting within the equipment that had this tag. I wish that I could take credit for Mr. Angry, but someone else came up with this icon that is widely used in hazard and warning labels.
I got an opportunity to see the reaction of a 4-year-old boy one day. We were walking
on a dock and were passing a power transformer with a Mr. Angry sign on it.
I said, "Look at that," pointing to the sign.
The boy’s reaction was swift and unambiguous, his eyes widened and he steered a wide path
around the transformer. I was sold.
The original manufacturer’s cover that was too small. The cover was supposed to shield a set of terminal lugs that carried 480 volts of alternating current. The cover had a lettered warning that was difficult to read. Anyone wanting to read it would have to lean in much too close to the live terminals. The design was working against itself - to deadly effect.
The label in the picture is the cover/warning label that I designed and built to protect people from coming into contact with the set of lugged terminals. (The mounting tabs can be seen at the bottom of the image). I incorporated Mr. Angry with the simple declarative message in an easy to read design that would not require much more than a glance to get the message.