The National Occupational Classification (NOC) system is used by Federal statistical agencies to classify workers into occupational categories for the purpose of collecting, calculating, or disseminating data. All workers are classified into one of about 500 unit groups according to their occupational definition. To facilitate classification, unit groups are combined to form about 150 minor groups, about 40 major groups, and 11 broad occupational categories.
The NOC system uses codes to divide occupations into four levels: major groups, minor groups, broad occupations, and detailed occupations.
Example
3: Health occupations (Broad occupational category)
32: Technical occupations in health (Major group)
322: Technical occupations in dental health care (Minor group)
3222: Dental hygienists and dental therapists (Unit group)
Lightcast currently uses the NOC 2021 Version.