Standards & Resources
The official rulebooks and databases behind every commercial scale in America — all free. Updated July 11, 2026.
NIST Handbook 44
The national rulebook — specifications, tolerances, and technical requirements for weighing devices, updated annually and adopted into state law. When an inspector tests your scale, this is the standard they test against. Current edition: 2026, free.
NTEP Certificate Database
Every legal-for-trade device model carries a Certificate of Conformance issued through NTEP. Verify any scale's CC number, search by manufacturer or model, and download certificates — free and public.
NCWM
The National Conference on Weights and Measures — where state officials, industry, and federal advisors set U.S. weights and measures policy, run NTEP, and vote the annual Handbook 44 updates.
NIST Office of Weights and Measures
Publishes the handbooks, trains state inspectors and metrologists, and supports the state laboratories that keep America's measurements traceable. Sets the standards — your state or county does the inspecting.
OIML — international type approval
The International Organization of Legal Metrology maintains the OIML Certification System: type-approval certificates for weighing instruments (R76), load cells (R60), and more, recognized across member states worldwide. Many manufacturers hold both NTEP and OIML approvals.
Measurement Canada
Canada's legal-metrology authority: device Notices of Approval, mandatory examinations, and the authorized service providers who inspect trade devices across every province. The Canadian counterpart to the NIST/NTEP system.
Your state's rules & licensed service companies
Every state applies these standards its own way. Our directory covers all 51 jurisdictions, and each state page links the official registry of licensed scale service companies where the state publishes one.