The Reason Why Stop Signs Are Red

Roman_Gorielov, iStock/Getty Images Plus
Roman_Gorielov, iStock/Getty Images Plus

Why is red the standard color for stop signs? The short answer is this: because the representatives of the First National Conference on Street and Highway Safety in 1924 decided so.

Though stop signs were still a relatively new idea in the United States back in the 1920s—Detroit erected the first one around 1915, Jalopnik reports—the “red means ‘stop’” custom dates back to 1841, when Henry Booth of the Liverpool and Manchester Railway suggested using red to indicate danger on railroads. London then adopted the color for its regular traffic lights in 1868, and the United States eventually followed suit.

The First National Conference on Street and Highway Safety, called by then-Secretary of Commerce Herbert Hoover in 1924, aimed to standardize the color coding of road signage. It established that for all “signs and signals, both luminous and nonluminous,” red should indicate “stop,” green should indicate “proceed,” and yellow should indicate “caution,” according to the report released after the conference [PDF]. It was also decided that distance and direction signs should be black and white.

That all probably sounds familiar if you’ve ever seen a street before, but implementing the mandate for red stop signs posed immediate issues. A red material that wouldn’t fade over time just didn’t exist in 1924, Gene Hawkins, a professor of civil engineering at Texas A&M University, told The New York Times in 2011. So the writers of the 1935 Manual on Uniform Traffic Control Devices chose the next best thing: yellow. The manual also specified that every sign should be octagonal, another idea from the 1920s.

California was first to figure out that porcelain enamel would resist fading and erect red stop signs across the state, a practice noticed and addressed in the 1954 revision [PDF] to the Manual on Uniform Traffic Control Devices. Now that red was more logistically feasible, the committee in charge of updating the manual decided there should be no more yellow stop signs.

We don’t know exactly why Henry Booth and other early industrialists felt that red aptly signaled “stop.” Maybe they thought it was harder to overlook than blue or green, which natural surroundings like water and foliage might easily camouflage. Maybe they felt red, like fire or blood, just went along well with danger.

There may also be a deeper reason. When, as part of a 2011 study, red-, blue-, and green-clad human experimenters offered apple slices to individual monkeys in a free-range facility, the monkeys seemed to have an aversion to taking slices left by the experimenter wearing red. Perhaps our association of danger with the color red has a psychological basis we don’t fully understand yet.

[h/t Jalopnik]

10 of the Most Popular Portable Bluetooth Speakers on Amazon

Altech/Bose/JBL/Amazon
Altech/Bose/JBL/Amazon

As convenient as smartphones and tablets are, they don’t necessarily offer the best sound quality. But a well-built portable speaker can fill that need. And whether you’re looking for a speaker to use in the shower or a device to take on a long camping trip, these bestselling models from Amazon have you covered.

1. OontZ Angle 3 Bluetooth Portable Speaker; $26-$30 (4.4 stars)

Oontz portable bluetooth speaker
Cambridge Soundworks/Amazon

Of the 57,000-plus reviews that users have left for this speaker on Amazon, 72 percent of them are five stars. So it should come as no surprise that this is currently the best-selling portable Bluetooth speaker on the site. It comes in eight different colors and can play for up to 14 hours straight after a full charge. Plus, it’s splash proof, making it a perfect speaker for the shower, beach, or pool.

Buy it: Amazon

2. JBL Charge 3 Waterproof Portable Bluetooth Speaker; $110 (4.6 stars)

JBL portable bluetooth speaker
JBL/Amazon

This nifty speaker can connect with up to three devices at one time, so you and your friends can take turns sharing your favorite music. Its built-in battery can play music for up to 20 hours, and it can even charge smartphones and tablets via USB.

Buy it: Amazon

3. Anker Soundcore Bluetooth Speaker; $25-$28 (4.6 stars)

Anker portable bluetooth speaker
Anker/Amazon

This speaker boasts 24-hour battery life and a strong Bluetooth connection within a 66-foot radius. It also comes with a built-in microphone so you can easily take calls over speakerphone.

Buy it: Amazon

4. Bose SoundLink Color Bluetooth Speaker; $129 (4.4 stars)

Bose portable bluetooth speaker
Bose/Amazon

Bose is well-known for building user-friendly products that offer excellent sound quality. This portable speaker lets you connect to the Bose app, which makes it easier to switch between devices and personalize your settings. It’s also water-resistant, making it durable enough to handle a day at the pool or beach.

Buy it: Amazon

5. DOSS Soundbox Touch Portable Wireless Bluetooth Speaker; $28-$33 (4.4 stars)

DOSS portable bluetooth speaker
DOSS/Amazon

This portable speaker features an elegant system of touch controls that lets you easily switch between three methods of playing audio—Bluetooth, Micro SD, or auxiliary input. It can play for up to 20 hours after a full charge.

Buy it: Amazon

6. Altec Lansing Mini Wireless Bluetooth Speaker; $15-$20 (4.3 stars)

Altec Lansing portable bluetooth speaker
Altec Lansing/Amazon

This lightweight speaker is built for the outdoors. With its certified IP67 rating—meaning that it’s fully waterproof, shockproof, and dust proof—it’s durable enough to withstand harsh environments. Plus, it comes with a carabiner that can attach to a backpack or belt loop.

Buy it: Amazon

7. Tribit XSound Go Bluetooth Speaker; $33-$38 (4.6 stars)

Tribit portable bluetooth speaker
Tribit/Amazon

Tribit’s portable Bluetooth speaker weighs less than a pound and is fully waterproof and resistant to scratches and drops. It also comes with a tear-resistant strap for easy transportation, and the rechargeable battery can handle up to 24 hours of continuous use after a full charge. In 2020, it was Wirecutter's pick as the best budget portable Bluetooth speaker on the market.

Buy it: Amazon

8. VicTsing SoundHot C6 Portable Bluetooth Speaker; $18 (4.3 stars)

VicTsing portable bluetooth speaker
VicTsing/Amazon

The SoundHot portable Bluetooth speaker is designed for convenience wherever you go. It comes with a detachable suction cup and a carabiner so you can keep it secure while you’re showering, kayaking, or hiking, to name just a few.

Buy it: Amazon

9. AOMAIS Sport II Portable Wireless Bluetooth Speaker; $30 (4.4 stars)

AOMAIS portable bluetooth speaker
AOMAIS/Amazon

This portable speaker is certified to handle deep waters and harsh weather, making it perfect for your next big adventure. It can play for up to 15 hours on a full charge and offers a stable Bluetooth connection within a 100-foot radius.

Buy it: Amazon

10. XLEADER SoundAngel Touch Bluetooth Speaker; $19-$23 (4.4 stars)

XLeader portable bluetooth speaker
XLEADER/Amazon

This stylish device is available in black, silver, gold, and rose gold. Plus, it’s equipped with Bluetooth 5.0, a more powerful technology that can pair with devices up to 800 feet away. The SoundAngel speaker itself isn’t water-resistant, but it comes with a waterproof case for protection in less-than-ideal conditions.

Buy it: Amazon

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Why Are Decaf Coffee Pots Orange?

If you're looking for a caffeine fix, you know that orange pot isn't going to help.
If you're looking for a caffeine fix, you know that orange pot isn't going to help.
RonBailey/iStock via Getty Images

The orange spout and handle on a decaf coffee pot have saved many caffeine lovers from having a terrible morning. Like the orange on a traffic cone, the color has become a signal both to the people who drink coffee and the servers who pour it. But the shade wasn't merely chosen for its eye-catching qualities; orange is a piece of branding left over from the original purveyors of decaf java.

According to The Cubiclist, decaffeinated coffee first arrived in America via the German company Sanka. Sanka (a portmanteau of the words sans and caffeine) sold its coffee in stores in glass jars with orange labels. The bright packaging was the company's calling card, and because it was the first decaffeinated coffee brand to hit the market, consumers started looking for the color when shopping for decaf.

In 1932, General Foods, which has since merged with Kraft, purchased Sanka and got to work promoting it. To spread the word about decaf coffee, the company sent orange Sanka coffee pots to coffee shops and restaurants around the country. Even if the waitstaff wasn't used to serving two types of coffee, the distinct color of the pot made it easy to distinguish decaf from regular.

The plan was such a success that orange eventually became synonymous not just with Sanka, but all decaf coffee. Other coffeemakers began offering decaffeinated alternatives, and when marketing their products, they chose the color Sanka had already made popular.

The reason for the orange coffee pot is just one of decaf's not-so-mysterious mysteries. Here's some of the science behind how exactly coffee makers get the caffeine out of the beans.

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