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California's Sealers of Weights and Measures

"Protecting Agriculture, the Environment, Consumers and Business."

Responsibilities and Duties

Each year county weights and measures officials inspect and test packaged commodities and all commercially used devices. Transactions derived from the use of such devices are also inspected for accuracy. In addition to inspection activities, weights and measures officials provide education and training to the public as well as the regulated industries. Your weights and measures official is a "third party" to virtually any transaction you may make based upon the activities in the following programs.

County Sealers of Weights and Measures carry out the programs listed below to accomplish these aims:

  • Service Agents
  • Devices
  • Quantity Control
  • Weighmaster
  • Petroleum Products

Service Agents

Persons that sell, rent, install, service, or repair commercial weighing and measuring devices are required to be licensed with Division of Measurement Standards (DMS). The lawful licensing of repairpersons by DMS assists with the integrity of the repair industry and traceability of their standards to NIST. Repairman must report their work to county weights and measures officials. This allows for efficient review of their work to validate the accuracy of that work and to verify the appropriate use of devices.


County Weights and Measures Inspectors inspect and test various types of weighing and measuring devices throughout the county. Examples of some of the types of devices inspected are: gasoline dispensers, propane/butane meters, electric meters, taxi meters, odometers on ambulances, farm milk tanks, pharmacy scales, deli counter scales, livestock scales, concrete batch plant scales, truck scales, etc. All such devices are under the scrutiny of weights and measures. They are tested for accuracy and inspected to determine if they are appropriate for their intended use. Once that is determined the inspector certifies the device by affixing a paper seal to it.

Quantity Control

Now that we have certified the devices, how can you know you are getting what you have paid for? The Quantity Control program provides that answer. From time-to-time inspectors conduct inspections on packaged goods using statistical sampling procedures to determine if the proper weight, measure or count is being used. As part of the same inspections, package labeling is examined for compliance with the basic labeling requirements as set by laws and regulations.Test purchases are made at various establishments throughout the county in order to check the accuracy of transactions. Goods are selected at random and a purchase is made to determine if customers are being charged the advertised price. Consumer complaints received by the department are investigated in this manner to check for any discrepancies. Any commodity whether bought, sold, traded, bartered, etc. can be checked by weights and measures.


In one-way or another, all of commerce is affected by the activities of weighmasters. Weighmasters are persons who are licensed by DMS to certify the weighed, measured, or counted quantity of any commodity. The certificates issued by weighmasters are recognized by courts of law as being a legal document. As such, there are criteria that must be followed by weighmasters when issuing weighmaster certificates. Training is provided and inspections are performed by county weights and measures officials to en-sure the correctness of the certificates issued.

Petroleum Products

Nationally, the Petroleum Program run by weights and measures in California is unique. Locally, weights and measures officials enforce that portion of the California Business and Professions code relating to petroleum product quality standards. From time-to-time, random samples are taken to insure product compliance with national standards. Undercover purchases are made to investigate consumer complaints and to inspect the accuracy of the transactions. Undercover purchases also serves as a method for gathering samples of products used for determining compliance with standards. Labeling regulations are also strictly enforced to provide product identity and information to the seller and the consumer.