Yes, the calibration standards are international, and all national laboratories follow these uniform standards through an organization known as BIPM (International Bureau of Weights and Measures). You can learn more about BIPM here: BIPM.
While NIST (National Institute of Standards and Technology) is the relevant organization in the US, other countries have their own equivalents. For example, Justervesenet handles this role in Norway, and UKAS performs similar functions in the UK.