How tall are you? How old? How much do you weigh? Do you care? Is it important to you that the measurements for height, age, and weight are accurate? What about the measurement of the gasoline that you pump into your tank? Is it important that the 12 gallons you pay for are truly 12 gallons?

Measurement is part of our daily lives, and accurate measurements make our complex society run smoothly. At NIST, we measure many vital quantities, such as time, temperature, and the flow of gases and liquids as accurately as possible, using, whenever possible, standards relating to the unchanging properties of atoms.

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