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Division of Measurement Standards: Metrology Program


Weighing DeviceMetrology is the science of measurement and is the basis of weights and measures. The State Metrology Laboratory keeps and maintains standards of weight, volume, time, temperature, and length that are used to ensure accuracy for weights and measures in the state of California.

These physical standards form the legal and scientific basis for commercial transactions in California involving weights and measure. The values of these standards are traceable to national and international standards. The photograph on the front of the Information Guide is of the international prototype kilogram that is kept near Paris, France. The value of all weights used in the United States and California can be traced back to this one object. Other standards can be traced to naturally occurring physical phenomena, for example: atoms and protons emitted at various wave lengths, electrical forces relating to constants, and the speed of light in a vacuum.

The Metrology Program is responsible for:

  • Certification of state and county weights and measures standards.
  • Maintenance of recognized certification standards.
  • Providing scheduling and pricing information.
  • Certification of weights and measures standards, for a fee, among registered service agencies, local agencies, industry, and the general public.

The Metrology Program maintains, in concert with the National Institute of Standards and Technology, the State standards of measurement. These physical standards form the basis for California transactions involving weight or measure. For more detailed information about the Metrology Program, please refer to the Information Guide ,located in the list of More Resources.

Certificate of Metrological Traceability