Did you know that 90 percent of the world uses the metric system? In fact, only Myanmar (Burma), Liberia and the United States use a different form of measurement. That’s pretty amazing when you think about it. That means for virtually any translation or interpretation project that involves measurement—like length, mass, volume, area, even temperature—you need to be extra careful about how they are communicated.
In some cases, you might want the conversion to be an exact translation, but not always.
When it comes to translating measurements, first consider how precise you need to be. For example, when warning consumers to store a gas cylinder at least “three feet” away from an open flame, you probably would not want to use a literal translation. Three feet actually equates to “0.9144 meters,” so in this instance, rounding off to say “one meter” would be acceptable. Those few tenths of a millimeter won’t matter in this situation, and the smooth flow of your copy will be preserved.
On the other hand, measurement units for tools and machinery need to be very specific. Wrench, nut and bolt sizes are a common example, and we frequently see this mishandled in amateur translations. When a 5/8” wrench is required, that’s exactly what must be communicated in any language. Specifying only 1.5875 cm (or much worse, rounding it to 1.6 cm) leaves the user not knowing which tool is required, or possibly stripping the nut because of a misleading conversion in the translation!
All of this is relative to the scale, and the significant digits in the original measurement. When providing high-altitude recipes for cookie batter at 3,000, 5,000 and 7,000 feet, it doesn’t make things any “clearer” to the audience if you specify 914.4, 1,524 and 2,133.6 meters in your French translation. On other hand, when a component is only several centimeters long in the first place, fractions of a millimeter can often be very important.
Sometimes you might want to include both English and metric measurements—either to ensure that units used in the original situation or component are retained, or to provide approximations that help your audience get a sense of the sizes, weights or distances involved. In translation, as a general rule the common measurement units of the target language appear first, followed by the original equivalent (within parentheses, for example). Again, the translation team must have sufficient knowledge of the subject matter—and common sense—to know when a word like “approximately” is called for, and the appropriate level of precision for each conversion.
However, there are exceptions to this default order, like the wrench example cited in the previous section, or where the product itself is supplied in English units—spools of cable in lengths of 100, 500 and 1000 feet, for instance. When documents are directed towards non-English-speaking populations within the U.S., it is also common to use English measurements—sometimes followed by their metric equivalents if that will provide additional clarity.
So when it comes to communicating measurements across countries, use common sense in deciding when to be exact and when to be “close enough.”
Metric Trivia:

• The famous platinum bar established as the meter standard in 1799 (at an international scientific meeting in Paris) was supposed to represent one ten-millionth of the distance from the North Pole to the equator.
• The measurement was wrong! We now know that this distance is actually 10,002,000 meters, and our standard meter is actually about 0.2 millimeters short of that exact proportion.
• Today’s definition of a meter: the distance traveled by light in a vacuum in one 299,792,458th of a second. Yeah, that makes it much easier to remember
• Thomas Jefferson devoted much effort to make the United States the second nation in the world to adopt the metric system. Obviously, he was unsuccessful. However, it should also be noted that France, the birthplace of the metric system, was reverted to the older system of measurements (livre, aune, etc.) by Napoleon in 1812, and didn’t complete full conversion back to the metric system until the end of World War I.

For more than 30 years, ASIST Translation Services, Inc. has worked with business, government, educational and non-profit clients around the world. We improve foreign language communications through a full menu of translation and interpreting services, including content localization, studio voice recording & audio-visual production, transcreation, proofreading, website content, page layout & design, cultural training, and other specialized language support. To learn more about how we can assist you, visit our LinkedIn, Twitter or Facebook pages or our Website!