Why is Yellow a Safety Colour?

Why is Yellow a Safety Colour?

Signs are important when it comes to promoting safety in the workplace and in public spaces. Other than the symbols drawn on the signs, the sign’s colour plays a crucial role in making sure that they draw attention and are easily seen even from afar. Certain colours, especially when it comes to safety signs, have specific meanings, which are recognised universally regardless of language or country.

Yellow is one of the most commonly used colours to indicate hazards.

More specifically, this colour denotes potential threats to one’s safety. But have you ever wondered why, of all colours, is yellow used as the ‘safety’ colour?

Why is Yellow a Safety Colour? »

How did yellow become the colour for safety

Yellow has always been known to be an energetic and cheerful colour. In colour psychology, this symbolises positive emotions such as fun, youth, optimism, confidence, and happiness. Yellow inspires thinking and stimulates learning. So when, and why, did people start using it in signs to indicate safety and caution?

It was around the 20th century when yellow began to be valued for its high visibility. It can be seen well from afar and even from fast-moving vehicles, making it the ideal colour for road safety signs. It is also used for things that need to be spotted easily, such as road repair equipment, taxi cabs, school buses, fire trucks, and other emergency vehicles.

Yellow signals warning or caution and is used in signs worldwide to prevent accidents. Here in Australia, the Australian Standard AS1318 or the SAA Industrial Safety Colour Code, assigned yellow as the basic colour to indicate places where caution should be observed and exercised, and identify areas where hazards from radiation exist.

Why yellow? The science behind it

In order for you to understand why yellow became the official colour for safety, not only in the country but also in other parts of the world, you have to know how our eyes and brain perceive this colour.

When light hits a certain object, the object absorbs some of it, while some are reflected. This reflected light enters our eyes and reaches specialised receptors called cones. These cones get excited as the light hits them and they send signals to the brain. Different light wavelengths stimulate specific combination of cones, making us perceive the different colours. The red and green cones in our retina are highly sensitive to light.

When we see yellow, both of these types of cones are excited to almost peak intensity. In addition to that, other parts of the eye reduce sensitivity to violet and blue light, making yellow appear to be the brightest among all the colours in the spectrum. Another unique characteristic of yellow is that even most colour-blind individuals can see it.

Using yellow as a background for a black text provides maximum visibility and readability whether it’s day or night. This makes yellow the perfect colour for safety signs.

Safety signs that use yellow

As mentioned above, yellow is the best colour to indicate caution because it can draw attention and is hard to miss even from a distance, giving us time to avoid the hazard. For these reasons, yellow warning signs are used in many different cases. For example, in a manufacturing business or in the case of road maintenance, the workplace exposes workers and visitors to risk factors that may cause injuries or death.

Yellow is used for signs that mark physical hazards, caution tags and labels, conveyors, overhead fixtures, rails, low beams and door projections that may be bumped into; areas with high voltage electricity; crane hooks and pulley blocks; and storage and containers for flammable and corrosive materials.

Knowing the right type and colour of safety signs to use is crucial in every workplace and public spaces, especially if there are possible hazards that could cause physical harm and damage to people and property. If you want to learn more about safety signs, contact Verge Safety Barriers now!

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