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Injuries, Illnesses, and Fatalities

Request for Comment - Occupational Injury and Illness Classification System (OIICS), Version 3.0

The Bureau of Labor Statistics (BLS) is soliciting comments on the completed draft of Version 3.0 of the Occupational Injury and Illness Classification System (OIICS). This version will replace the current version 2.01 in use since 2011. BLS requested preliminary comments for OIICS revisions in the Request for Comment which appeared in the Federal Register (82 FR 47770) in 2017.

Submitting comments

Written comments or questions may be submitted by email to: on or before November 6, 2020.

Link to materials for review

  • Nature of injury or illness changes, coding rules, and structure (XLSX)

  • Part of body changes, coding rules, and structure (XLSX)

  • Event or exposure changes, coding rules, and structure (XLSX)

  • Source of injury or illness changes, coding rules, and structure (XLSX)

  • Worker activity changes, coding rules, and structure (XLSX)

  • Location changes, coding rules, and structure (XLSX)


Additional information


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BLS is responsible for the developing and publishing occupational injury, illness, and fatality data. These data are compiled from the Survey of Occupational Injuries and Illnesses (SOII) and the Census of Fatal Occupational Injuries (CFOI) programs. The OIICS was originally developed for use by these programs to classify certain case characteristics associated with the nonfatal and fatal work injury cases collected by the programs. Since its creation, OIICS has also been adopted by several state workers’ compensation agencies, the National Institute for Occupational Safety and Health (NIOSH), and other safety and health organizations. For more information on OIICS and past versions of the classification system see

Alignment with data users’ areas of interest

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OIICS 3.0 was developed with an intent to consolidate and highlight known areas of data user interest wherever possible.

  • BLS has solicited and received input from OSHS data users and other OIICS stakeholders prior to beginning work on OIICS 3.0 and throughout the revision process
    • Centers for Disease Control and Prevention (CDC) National Institute for Occupational Safety and Health (NIOSH)
    • NIOSH National Occupational Research Agenda (NORA) Committees
    • Northeast Center for Occupational Safety Agriculture, Forestry and Fishing Division
    • Occupational Safety and Health Administration (OSHA)
    • National Academies of Science (NAS)
    • BLS State cooperative partners

  • Consulted multiple other safety classification structures and sought to align OIICS as much as possible so that data can be more easily compared between sources
    • International Classification of Diseases (ICD-10)
    • National Highway Traffic Safety Administration (NHTSA) Fatal Accident Reporting System (FARS) motor vehicle “Body Type” classifications
    • Pipeline and Hazardous Materials Safety Administration (PHMSA) Hazardous materials classifications
    • National Transportation Safety Board (NTSB) Aviation crash reporting
    • Veterans Health Administration National Drug File (VANDF) Drug coding

Updating the structure to reflect technological change and current state of workplace hazards

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  • Addition of two new structures: Worker Activity and Location
    • NEW Worker Activity: The activity or task that the worker was performing at the time the injury or exposure occurred.
    • NEW Location: The type of location or premises where the injury or exposure occurred.
    • These data elements are currently used in the Census of Fatal Occupational Injuries (CFOI). There are no plans currently to use them for the Survey of Occupational Injuries and Illnesses (SOII).

  • Codes were added to reflect new technologies and materials that were not widely in use at the time of the development of OIICS 2.01.
    • Examples include new types of building materials, new types of machines, such as drones, and technologies such as self-driving vehicles.
    • See summary of content revisions for each variable above

Better accommodation of varying levels of case detail

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This revision aimed to balance the challenges of coding incomplete or limited case detail, which is often seen on the SOII program, while maintaining the ability to capture the often high level of detail available in CFOI case narratives.

  • Focus on capturing unique concepts within each structure, reducing repetition of coded information and duplicative codes where possible
    • Example: The concept of “repetitive use versus single trauma” was removed from Nature of injury or illness and relegated exclusively to Event or exposure. This allowed for elimination of duplicate codes of the same medical condition when caused by different events in the Nature of injury or illness structure, which could cause coders to need to select an unspecified nature code when the distinction is not specified in case documents.

  • Hierarchical groups were revised as necessary to
    • Minimize loss of information where possible
    • Allow for meaningful aggregations of incomplete information wherever possible

Improved ease and consistency of coding

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BLS analyzed current coding, including frequency of code use, narrative analysis, past coding interpretations, and application of rules of selection. BLS made changes with an aim to improve ease and consistency of coding.

  • New manual format
    • This revision transitioned the primary format of the manual from a document or book format to a spreadsheet format to better organize information. Each code is now broken out into:
      • Code: The 3 or 4-digit number that represents that category in the structure
      • Title: The name that summarizes the category
      • Definition: A description of the code
      • Includes: Examples of what is included in that code
      • Excludes: Examples of what is excluded from that code
      • Coding interactions: Rules for when the selection of a specific code from one structure either mandates or excludes the selection of specific code(s) from another structure. For example, Nature of injury or illness code 1113: Concussion must be accompanied by a Part of body code 111: Brain.
    • Increased accessibility of coding rules and resources
      • Order of precedence: Refers to arranging the codes presented in the structure such that the nominal order in which the codes appear designates which codes should be given priority when multiple codes could be appropriate within a given case. OIICS 3.0 expands the application of order of precedence from just the Event or exposure structure to also include the Nature of Injury or Illness, Worker Activity, and Location structures.
      • Rules of selection: General guidance for how to select codes from each structure
        • NOTE: This field is still under development pending the completion of the structure testing phase.
      • Code interactions: Each code or group of codes will be accompanied by guidance referring to dependencies or interactions between codes from other structures
        • Example: If a code from Nature of injury or illness 111: Intracranial injuries has been selected, then Part of body must =111: Brain
        • NOTE: This field is still under development pending the completion of the structure testing phase
      • Increase cross-referencing of terms and codes in the ‘Includes’ and ‘Excludes’ fields
      • Improved definitions of codes to assist with common areas of coder confusion
      • Revision or elimination of ambiguous or logically unnecessary codes wherever possible
        • Codes are mutually exclusive where possible
        • Codes are logically exhaustive where possible
        • Unspecified and n.e.c. (not elsewhere classified) codes that would logically not be used have been removed


Last Modified Date: September 14, 2020