Official definition

This U.S. industry comprises establishments primarily engaged in manufacturing measuring and controlling devices (except search, detection, navigation, guidance, aeronautical, and nautical instruments and systems; automatic environmental controls for residential, commercial, and appliance use; instruments for measurement, display, and control of industrial process variables; totalizing fluid meters and counting devices; instruments for measuring and testing electricity and electrical signals; analytical laboratory instruments; irradiation equipment; and electromedical and electrotherapeutic apparatus). Illustrative Examples: Aircraft engine instruments manufacturing Automotive emissions testing equipment manufacturing Clocks assembling Meteorological instruments manufacturing Physical properties testing and inspection equipment manufacturing Polygraph machines manufacturing Radiation detection and monitoring instruments manufacturing Surveying instruments manufacturing Thermometers, liquid-in-glass and bimetal types (except medical), manufacturing Watches (except smartwatches) and parts (except crystals) manufacturing Cross-References. Establishments primarily engaged in--