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Emotional response -

When people look at universal symbols, they are often able to understand the feelings these symbols are meant to evoke. Even if people are not sure what the symbols mean precisely, they are still aware of their cultural context. But symbols inevitably change their meaning.

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The Jolly Roger -

The Jolly Roger is an example. Although it was once a symbol of death, pirates, and poison, it is now more associated with treasure, Halloween, and movies. Once feared worldwide, its association with danger has faded.

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Ubiquity -

The world is full to bursting with icons that are designed to warn people of things that they need to stay away from or even things that they should not do.

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Universal symbols -

Symbols that convey danger need to transcend generations and languages. However, designing such symbols is incredibly difficult. Many modern icons lose their impact over time, and require strategic and memorable designs to communicate effectively.

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Origins -

In the early 20th century, warning symbols for biohazards lacked standardization. Different organizations used inconsistent designs, like the US Army’s inverted blue triangle and the Navy’s pink rectangle. This created potential risks of miscommunication and accidental exposure.

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A universal symbol -

The lack of a universal biohazard symbol inspired engineers from Dow Chemical (pictured) to create one in 1966. Their mission was to design a striking, unique, and understandable symbol to clearly communicate biological danger and prevent laboratory accidents.

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The six criteria -

Dow Chemical’s team set six design criteria: visual impact, uniqueness, immediate recognition, stenciling ease, rotational symmetry, and acceptability across cultures. These guidelines were essential to ensure global understanding and efficient communication of hazardous biohazards.

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1. Visually striking -

The biohazard symbol needed to grab attention instantly, eliminating simple shapes used by the Army and Navy. An impactful visual presence was necessary, as life-threatening dangers demanded an icon that would make a stark impression on people.

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2. Unique and unambiguous -

The biohazard symbol also needed to be unique and unmistakable, preventing confusion with existing medical or general hazard symbols like the snake-and-staff. It was critical to ensure the icon wasn’t interpreted as representing something unrelated or misleadingly safe.

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3. Recognizable and memorable -

Quick recognition and recall were crucial. People had to easily remember the symbol after seeing it. This requirement ensured that, even if individuals had little prior knowledge, the icon would stay imprinted in their minds as a danger sign.

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4. Easy to stencil -

The fourth criteria is that the symbol had to be simple enough to be easily replicated using basic tools like a straightedge and compass. This stenciling requirement allowed for easy and widespread implementation in safety signage.

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5. Rotational symmetry -

The engineers also made clear that the symbol had to be rotationally symmetrical, so that it would appear the same from every angle. This symmetry prevented misinterpretation in environments where consistent visibility and understanding were critical.

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6. Universal acceptability -

Lastly, the symbol’s design needed to be acceptable to all groups, regardless of cultural or social background. Achieving a global, inclusive symbol ensured the biohazard marker’s meaning could be understood without relying on specific cultural knowledge or biases.

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Experiment -

The team at Dow Chemical conducted an experiment to ensure the symbol’s effectiveness according to the criteria. They tested 24 icons (made up of six newly-designed biohazard markers and 18 common symbols) on 300 people across 25 cities, and compared the memorability and meaning of the icons.

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Testing -

Participants viewed 24 symbols, including new designs and familiar logos. They guessed the symbols' meanings, which were aggregated into a scale based on meaningfulness. The participants returned a week later to identify the remembered symbols. Ultimately, one symbol stood out.

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The new biohazard symbol -

Among the six biohazard designs, the current symbol emerged as the most memorable and also the least meaningful. This combination allowed it to be easily remembered, but left enough of a blank slate so that designers could teach its meaning to others.

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Visual simplicity and versatility -

The biohazard symbol’s simplicity means that it is easy to draw using minimal tools. Unlike other hazard symbols, it doesn’t reference any physical object, and its abstract design makes it versatile for various contexts.

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Enduring icons -

The biohazard symbol has remained effective for decades. Its design continues to protect people from dangerous materials that could remain so for millennia. As such, one question remains: can the meaning of these symbols withstand the test of time?

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The test of time -

Gregory Benford, an American physicist and science fiction writer, worked on the Waste Isolation Pilot Project (WIPP) and analyzed communication methods for dangers that last for thousands of years, like radioactive waste.

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The Waste Isolation Pilot Project -

Benford’s involvement with WIPP included determining the risk of someone intruding on a biohazard site during the next 10,000 years. Radioactive waste requires clear warnings for far-future generations, and the difficulty lies in developing a visual language that transcends human history.

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Outdated meaning -

The meanings of symbols inevitably change over time. As mentioned, the Jolly Roger evolved away from meaning poison or death. For biohazardous material, humanity needed a timeless symbol.

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Communicating danger -

Since the 1970s, many anthropologists, engineers, physicists, and behavioral scientists have posed various possible solutions to this particular problem.

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Adding context -

One approach that designers took was to add context. Designers could communicate danger using a three-frame cartoon that illustrates cause and effect. But this design makes many assumptions, including that the viewer reads left to right, and that the drawing itself would withstand wear and tear over millennia.

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Shape-based warnings -

The designers then considered creating shape-based warnings that didn’t rely on words or images. Proposals included spike fields, large pyramids, and eerie blocks, all of which evoke natural fear and discomfort. These shapes were intended to repel people instinctively from dangerous areas.

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The psychological dilemma -

But warning designs, like spike fields, are not entirely foolproof. People’s innate curiosity could turn what is meant to cause fear into fascination. Balancing the desire to repel intruders while attracting attention remains a fundamental dilemma in psychology.

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The atomic priesthood -

Linguist Thomas Sebeok proposed creating an “atomic priesthood” to preserve warnings about radioactive waste. This elite group would use rituals and myths to convey the danger through generations, leveraging cultural continuity rather than relying on changing languages or symbols.

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Glowing cats -

Philosophers François Bastide and Paolo Fabbri suggested genetically engineering glowing cats to sense radiation. Songs and myths about these bioluminescent creatures could become cultural warnings and teach future generations to associate glowing cats with deadly radioactivity.

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No definitive solution -

There’s no perfect answer for designing warnings that last thousands of years. Communication methods (like symbols, cultural practices, and physical structures) continue to evolve.

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The evolution of communication -

As humanity changes, so do our communication needs. Warning symbols must adapt along with these needs and reflect shifts in technology, culture, and visual literacy. Evolving our visual language is vital to prevent miscommunication of life-threatening risks over the years to come.

Sources: (Vox) (99% Invisible) (TED-Ed)

See also: The most outrageous acts of piracy in history

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