Frequently Asked Questions

OIICS History

OIICS Compatibility

OIICS Coded Data


OIICS Resources


OIICS History

Back to Top  When was OIICS developed?

The Bureau of Labor Statistics (BLS) released the OIICS in 1992. In 2007, the BLS edited the manual to provide clarification to coding directions and minor code title changes based on their years of experience using the system. The minor 2007 OIICS revisions did not result in a break in series for the BLS occupational injury and illness data systems.

In 2010, the BLS released a “comprehensive redesign” of the OIICS (v2.0) that updated the classifications and resolved numerous classification issues to improve coding and interpretation of occupational injury and illness data. Modifications and clarifications were released in 2012 (v2.01). Occupational injuries and illnesses occurring in 2011 and forward will be classified using OIICS v2.01. This change will result in a break in series for the BLS occupational injury and illness data systems.

Back to Top  When will OIICS be revised again?

The BLS will periodically update the OIICS.

Back to Top  How do I make suggestions for OIICS revisions?

Questions or comments about OIICS or BLS occupational injury data systems may be submitted electronically.

OIICS Compatibility

Back to Top  How does OIICS compare to other coding systems?

The OIICS was developed specifically to uniformly classify injuries and illness arising from hazards and exposures in the work environment. It was largely based on the American National Standards Institute’s Method of Recording Basic Facts Relating to the Nature and Occurrence of Work Injuries, ANSI Z16.2-1962, revised 1969. The 1995 revision of the ANSI Z16.2 standard was then based on the OIICS. In addition, the BLS made OIICS as compatible as feasible with the International Classification of Diseases, 9th Revision, Clinical Modification, released by the Public Health Service, Department of Health and Human Services in 1989. In revising OIICS in 2010, the BLS took into account the International Classification of Diseases, Tenth Revision (ICD-10).

Back to Top  How do OIICS Event and Source Codes compare to ICD external cause codes?

The International Classification of Diseases (ICD) coding system includes a classification structure for external causes of morbidity and mortality to characterize environmental events, circumstances, and conditions as the cause of an injury, poisoning, or other adverse effect. The ICD external cause codes include major divisions that cover incidents involving transportation; falls; exposure to mechanical forces, electrical current, radiation, temperature extremes, and smoke or fire; drowning; contact with hot or cold objects; poisoning; overexertion; and intentional injuries from violence, legal intervention, and self-harm. At the major division level the OIICS event or exposure and ICD external cause schemes are quite similar. At a more detailed level the ICD codes tend to specify the injury source at a macro level in combination with the event. Because the OIICS uses two codes to specify the event and injury source, the OIICS allows far more specificity in coding than the ICD external cause codes.

Back to Top  Is there a crosswalk between OIICS codes and ICD codes?

No crosswalk between OIICS codes and ICD codes has been developed. Limited comparisons can be made when selection rules and code definitions are similar. However, caution should be used when comparing OIICS-coded occupational data to ICD-coded data.

OIICS Coded Data

Back to Top  Why code injury and illness data with OIICS?

Systematic characterization of occupational injuries and illnesses aids researchers, safety professionals, employers, policy makers, and others to reduce occupational hazards and improve workplace safety interventions. By classifying injuries and illnesses with the OIICS, direct comparisons with national occupational injury and illness data provided by the BLS and NIOSH are possible. The hierarchical structure of the OIICS encourages coding to varying levels of specificity depending upon the level of detail available and assists aggregation of data results at levels meaningful to different organizational needs. See the BLS article: Using the BLS Occupational Injury and Illness Classification System as a Safety and Health Management Tool.

Back to Top  What OIICS coded injury and illness data are available?

The BLS annually reports the number of fatal occupational injuries by OIICS characteristics through their Census of Fatal Occupational Injuries (CFOI). Similarly, the BLS uses the OIICS to characterize nonfatal occupational injuries and illnesses that involved days away from work through their annual Survey of Occupational Injuries and Illnesses (SOII). NIOSH characterizes work-related injuries and illnesses treated in U.S. hospital emergency departments by using the OIICS event or exposure and source or secondary source of injury or illness classification schemes. These data are available through the NIOSH online Work-Related Injury Statistics Query System (Work-RISQS).


Back to Top  Why use the OIICS trees?

The online and downloadable OIICS coding resources provide a simple graphical interface to facilitate using and interpreting BLS and NIOSH injury, illness, and fatality data characterized with the OIICS. In addition, these tools provide easy access to complex hierarchical coding structures to aid in classifying work-related cases by others. Increasing the systematic use and understanding of OIICS through access to convenient tools such as these OIICS coding resources will benefit efforts to reduce workplace injuries and illnesses.

Back to Top  Why download the OIICS Coding Resource?

The desktop OIICS Coding Resource is a convenient electronic tool for users who code or interpret occupational injury and illness data, particularly data from the BLS and NIOSH. Making it available on your desktop generally increases the lookup speed and does not require an active Internet connection. The desktop application also provides the additional ability to

  • Print the code trees
  • Expand the tree structure completely for all branches
  • View all informational content simultaneously

OIICS Resources

Back to Top  Where do I find the alphabetical indices for OIICS?

The alphabetical index for each OIICS component is available in the OIICS manual. See Documents and Links for the manuals. Additionally, the indices are embedded in the OIICS tree search function. The search function looks for your specific search term in the alphabetic indices, the descriptive information and the code titles for each OIICS component selected.

Back to Top  Is a simple list of OIICS codes and titles available?

A list of codes and titles is provided in each OIICS manual. Also, for OIICS v2.01 the numeric codes and associated descriptive titles are available in a downloadable file on the Documents and Links page. The list is provided as a comma separate values file that may be imported into spreadsheets and other types of software applications.

Page last reviewed: December 9, 2023
Content source: National Institute for Occupational Safety and Health (NIOSH) Division of Safety Research