Bureau of Weights and Measures

​​​​​​​​​​​The Wisconsin Department of Agriculture, Trade an​d Consumer​ Protection (DATCP) conducts routine inspections to ensure that consumers receive their money's worth in Wisconsin stores. It also regulates petroleum storage tanks and fuel quality​. Find our weights and measures resources on this w​ebpage.​​

​​​What W​e D​o​​​​

  • Regularly monitor the accuracy of gas pumps, price scanners, scales, and package weights.
  • Investigate complaints involving ​w​eights and measures devices.
  • ​Review system design ​pre-installation plans for storage and dispensing system installations, modifications, and upgrades.
  • Permit, register, and inspect fl​ammable and combustible liquid storage tanks.
  • Inspect and test liquid petroleum products.
  • Credential companies and technicians who work with storage tanks and specific weights and measures devices​.​
  • Maintain the State of Wisconsin weight standards in the Wisconsin Weights and Measures Metrology Laboratory.
 find a service company              FIL​E A w&M COMPLAINT             report a spill
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Announcements​​​​​

New! ​Service Company Technician Exams: Wisconsin weights and measures service company technician exams are now available in-person and virtually through the National Council on Weights and Measures (NCWM). The last exam proctored by DATCP will take place on August 8, 2025. Please visit the NCWM's Registered Service Agent Exam Information webpage to learn more.

RVP Waiver: On April 28, 2025, the U.S. Environmental Protection Agency (EPA) issu​ed a waiver related to Reid Vapor Pressure (RVP) requirements. Learn more​ about Wisconsin's response to this waiver.​

DATCP acknowledges EPA final rulemaking on gasoline ethanol blends effective April 29, 2025. The US Environmental Protection Agency (EPA) issued a final rule on February 29, 2024, regarding 40 CFR Part 1090, Regulation of Fuels, Fuel Additives, and Regulated Blendstocks. Effective April 29, 2025, summer gasoline-ethanol blended fuels containing between 9 and 15 percent ethanol, retailed in Wisconsin within EPA Clean Air Act (CAA) attainment areas will have a Reid vapor pressure (RVP) limit of 9.0 psi. The retail summertime fuel regulation period is between June 1 and September 15. The EPA final rule can be found here. A press release announcing the EPA will uphold the effective date can be found here.​

Training Opportunities: ​​

  • Steel Tank Institute/Steel Fabricators Association (STI-SPFA) is offering their Cathodic Protection (CP) course June 10-12, 2025 in Madison, ​WI. STI/SPFA's CP course is focused on the real-world needs of individuals and companies that plan to conduct field testing of cathodic protection monitoring systems. Seating is limited and pre-registration is required. Register online at: STI/SPFA - Cathodic Protection Course - Madison WI​.​

Gasoline-Ethanol ​Blends Minimum Temperature: ​On October 4, 2024, DATCP issued a guidance document specifying enforcement discretion for fuel supply chain stakeholders at the minimum temperature for 50% evaporation for gasoline-ethanol blended fuels.​​​​

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​Quick Links

Fact Sheets   |   DATCP Consumer Protection   |   DATCP Business Trade Practices   |   DNR   |   DSPS​


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Weights and Measures

DATCP inspects and calibrates measuring devices
to ensure consumers get their money's worth.

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P​etroleum and ​Storage Tanks

Storage tank systems for petroleum and
hazardous liquids are regulated by DATCP.

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​Licensing, Permitting, and Registration

Learn about​ requirements for service companies,
weights and measures devices, and storage tanks​.

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Service Companies and Technicians

Service companies and technicians in Wisconsin
must be certified or licensed by DATCP.

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Laboratory Services

Thousands of tests are conducted every year in
DATCP's metrology and fuel quality lab.

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Training and ​Continuing Education

Tank installers and system inspectors must
receive continuing education to remain certified.

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