Fahrenheit Versus Celsius: Why the US Hasn't Converted

The United States is the only major industrialized country in the world that does not use the Celsius scale and the metric system as its predominant system of measurement, according to a report released by the National Institute of Standards and Technology.

"One of the strengths of the SI, International System of Units, commonly known as the metric system, is its simplicity and ease of use," according to NIST Metric Conversion Subject Matter Expert Elizabeth Gentry.

One of the factors that makes the Celsius scale seemingly easier to use is that most of the common temperature reference points are simpler and easier to remember when converted to Celsius.

This AccuWeather image shows common temperature reference points in both the Celsius and Fahrenheit scales.

For people that find it easier to actually calculate the conversion from Fahrenheit to Celsius, there is a relatively simple formula. You take the degree Fahrenheit that you want to convert, subtract 32, then multiply by 5/9.

There have been multiple attempts made to convert the United States over to the metric system in the past.

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Congress passed the Metric Conversion Act of 1975 in order to increase the use of the metric system in the United States. However, the Act called for a process of voluntary conversion, meaning that it is at the discretion of the American public to convert to the metric system.

"Because the U.S. Congress determined that metric system use would be voluntary, we anticipate the transition process to continue gradually, punctuated by increased use as consumers build familiarity with SI measurements," Gentry said.

There are many options available that can help increase familiarity with using metric temperature measurements.

Many online sources are now offering "dual" unit options, which offer temperature information in both Fahrenheit and Celsius. This is one way to help people familiarize themselves with the metric system because they are able to directly compare Celsius to the customary temperature scale used in the United States.

"Many of these new technologies have made it easier than ever for customers to select their preferred measurement units," Gentry said. "When set to degree Celsius, these tools can help users benchmark their experiences."

These dual unit options have been increasing in popularity, specifically in sites that deal with travel and tourism. It is important that American citizens are able to understand the weather conditions in other countries that they are traveling to that use the Celsius scale.

"Weather and climate can impact everything from the clothing a tourist packs, the outdoor activities they engage in, to the businesses that benefit when unseasonable weather drives tourists inside," Gentry said.

By Accuweather.com Staff Writer, Rachelle Gaynor

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