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Injuries, Illnesses, and Fatalities

Occupational Safety and Health Changes to OIICS, NAICS and SOC

In September 2010, the Bureau of Labor Statistics completed a major revision to the Occupational Injury and Illness Classification System (OIICS). The revised OIICS structure (OIICS 2.01) will be used beginning with reference year 2011 for both the Census of Fatal Occupational Injuries (CFOI) and the Survey of Occupational Injuries and Illnesses (SOII) programs. Because of the extensive revisions, data for the OIICS case characteristics for reference year 2011 represent a break in series with data for prior years. More information on OIICS can be found here: As a result of the break in series, new survey ID’s have been created for the public IIF databases ( for CFOI and SOII.

The Standard Occupational Classification (SOC) system is used to classify occupations for both CFOI and SOII. Beginning with reference year 2011, a revised version of the SOC system will be used to classify occupations. While the changes to the new structure (SOC 2010) were not extensive, comparisons of SOC 2000 and SOC 2010 occupations should be made with caution. More information on the 2010 SOC, including an overview of new items in SOC 2010, can be found here:

The North American Industry Classification System (NAICS) is used to classify industry for both CFOI and SOII. For reference year 2014, the CFOI and SOII programs will adopt a revised industry classification system, NAICS 2012, which will represent a break in series. More information NAICS can be found here:

For more information on changes in coding structures and the years to which they apply, see the IIF Timeline of Key Developments in our Handbook of Methods.


Last Modified Date: February 26, 2020