Next time you’re at the deli, look for a bright sticker on the scale. It certifies that the scale has been checked with weights traceable to NIST. The weights were checked against other weights that, in turn, were checked against weights maintained by NIST. This ensures that a pound is a pound anywhere in the country.

NIST works with federal, state, and local officials and with industry to ensure that products contain the labeled amount. This includes providing standards and calibrations for accurate measurement of everything from the amount of medicine in pills to the brightness of light bulbs.