Weights & Measures

Installation of Weighing and Measuring Devices

The Office of Weights and Measures receives numerous questions on the installation of weighing and measuring devices. "Legal for Trade" devices are required for commercial applications where product is sold by weight or by measure. Legal for Trade essentially means that a given device has received a Certificate of Conformance from a NTEP (National Type Evaluation Program) Approved laboratory and complies with the National Institute of Standards and Technology Handbook 44. To comply with State statute, Legal for Trade weighing and measuring devices must be installed and placed in service by a service agency registered in the State of South Dakota. For additional information, please refer to the section on Frequently Asked Questions (FAQs).

Most questions received by the Office deal with the installation of heavy scales including vehicle, livestock or hopper scales. Since the installation of these scales can be costly, it is imperative that the scale is NTEP- approved and properly installed to ensure that the scale is capable of being certified and sealed by a State Inspector. If a scale is not Legal for Trade or is improperly installed and placed in service, there is the potential that the State Inspector will reject or condemn the scale and be unable to apply a seal indicating that it has been "Tested and Found Correct".

To assist the public, the Office of Weights and Measures has two booklets available:

South Dakota Department of Public Safety
Regulations and Recommendations for
Selection, Installation, and Maintenance of
Vehicle and Livestock Scales (PDF)


South Dakota Office of Weights and Measures
Regulations for Hopper-Type Scale Installations (PDF)

These booklets provide written and visual explanations on these requirements. They are available free of charge by clicking the above links or by calling or e-mailing the Weights and Measures Office.

Regardless of the weighing or measuring device type, at installation (or following device repair), ARSD 20:01:06:09 requires that all equipment "...be set as close to zero tolerance as possible."