The Weights and Measures Bureau responsibilities, mandated in Title 30, Chapter 12, and Title 82, Chapter 15, MCA, and implemented in the Administrative Rules of Montana, ARM 24.351.101 through 1117 include licensing, inspecting, testing, and certifying all weighing or measuring devices used in commercial transactions in the State of Montana. Weights and Measures has adopted in part the 2023 editions of NIST Handbook 44 and NIST Handbook 130; see ARM for specific instances where Montana uses different standards.
Weights and Measures administers a program which registers companies and individuals who inspect, calibrate and repair weighing and measuring devices. In addition, the Bureau enforces laws and regulations pertaining to quantity control of prepackaged goods (net contents) and quality control of petroleum products (Octane). Finally, the program runs the state standards lab and maintains the state standards of mass and volume which are used to calibrate standards used in the state for testing commercial devices.