Handbook of Methods > Survey of Occupational Injuries and Illnesses

Handbook of Methods Survey of Occupational Injuries and Illnesses Presentation

Survey of Occupational Injuries and Illnesses: Presentation

The presentation of Survey of Occupational Injuries and Illnesses (SOII) data is released in the fall and contains two data components. One component, sometimes referred to as the summary, is released annually and provides estimates of numbers and incidence rates of employer-reported nonfatal injuries and illnesses at the industry level for all types of cases. The second component, sometimes referred to as case and demographics, is released biennially and provides estimates of numbers, annualized (covering the biennial period and expressed on an annual basis) incidence rates, and median days for detailed case circumstances and worker characteristics for both the subset of the cases that involved days away from work as well as cases with days of job transfer and restriction (DJTR). Prepared tables containing the data can be found for industry data and for case and demographics at https://www.bls.gov/iif/nonfatal-injuries-and-illnesses-tables.htm. A schedule of releases from the Injuries, Illnesses, and Fatalities program, which includes SOII, can be found at https://www.bls.gov/iif/news.htm.

Also, on the SOII homepages, you will find interactive charts, supplemental highlights, quartile incidence rates (for industries), and special profiles for various topics such as musculoskeletal disorders. For more information on methodology for calculating rates or a description of the variables collected and coded for SOII, see the Calculation section. All of the rates produced by the SOII program are published online.

In addition to national estimates, state-specific estimates on workplace injuries and illnesses are available for participating state agencies. A list of state agencies and their telephone numbers is available from U.S. Bureau of Labor Statistics (BLS) at (202) 691-6170 or online at https://www.bls.gov/iif/state-data.htm. The state page also contains a basic data table for each state as well as state nonfatal injury rates. (For methodology on calculating rates, please see the Calculation section.)

Data tools

A variety of tools are available both online and through special request to aid data users. To accommodate the series breaks in SOII (please see the History section for more information) the online data tools can be run for the periods 1992–2002, 2003–10, 2011–13 (industry data), and 2011 forward (case and demographics) individually, but cannot cross over these time periods.

Profiles on the Web

The Profiles on the Web system allows users to create customized tables of the number or incidence rate of work-related nonfatal injuries and illnesses based on user-specified criteria. This is a good way to get an overview of the data available in an area of interest, both in magnitude and detail.

Databases

There are various ways to obtain very specific data points available from the Injuries, Illnesses, and Fatalities (IIF) program database available at https://www.bls.gov/iif/data.htm. Data users may use a single-screen or multiscreen data search interface to enter search criteria (both obtain data from the same source and provide the same types of output). Output data are presented in HTML, text, or Excel formats (per user preference). Each data point returned is associated with a unique series identifier (ID) and reference period. The series identification (ID) is composed of a series of codes associated with various survey classification titles. For additional information on series IDs, see https://download.bls.gov/pub/time.series/is/ for employer-reported nonfatal injuries and illnesses at the industry level, https://download.bls.gov/pub/time.series/cs/ for data related to case and worker characteristics from 2011–20, and https://download.bls.gov/pub/time.series/cb/ for biennial data related to case and worker characteristics from 2021 onward. (Please read the .txt files first.)

If you already know the specific series ID that you wish to obtain data for, you may use the series report tool https://data.bls.gov/cgi-bin/srgate to simply enter the series ID without having to enter search criteria.

You can also find discontinued data series (resulting from the breaks in series) at the bottom of the database page.

Flat files

Flat files containing all SOII estimates are available through the BLS download server site. Each data series on the BLS download site includes a two-character series designator. Clicking on the series designator expands the directory to provide a list of the files included with each series. Included with each series (generally the last file in each series directory) is a text file that provides: (1) a survey definition and a listing of the FTP files listed in the survey directory; (2) time series, series file, data file, and mapping file definitions and relationships; (3) series, data, and mapping file formats and definitions; and (4) a data element directory. The SOII series have experienced several breaks due to changes in coding systems. Data from these separate series may not be comparable to one another. Consequently, the following flat file series identifiers cover available SOII data reflective of these series breaks:

SOII — Summary data series:

hs — 1976–88 (1972 SIC)
sh — 1989–2001 (1987 SIC)
si — 2002 (New Occupational Safety and Health Administration recordkeeping)
ii — 2003–13 (2007 NAICS)
is — 2014 forward (2012 NAICS)

SOII — Case and demographics data series:

cd — 1992–2001 (1987 SIC)
hc — 2002 (New Occupational Safety and Health Administration recordkeeping)
ch — 2003 forward (2007 NAICS)
cs — 2011–20 (OIICS 2.01)
cb — 2021–22 forward (biennial estimates)

Special tabulations

Additional data may be available through contacting the SOII program directly. Special data queries with multiple cross-tabulations for multiple or aggregated years may be run upon request (with some limitations). To request such data, email iifstaff@bls.gov.

SOII microdata

SOII data are collected under a pledge of confidentiality and are protected under the Confidential Information Protection and Statistical Efficiency Act of 2002 (CIPSEA).

BLS allows limited access to SOII microdata for safety researchers and others involved in promoting safety in the workplace. The microdata are available onsite at the BLS national office in Washington, D.C., or at Federal Statistical Research Data Centers (FSRDCs) to researchers who agree to protect the confidentiality of the data and have the safeguards in place to do so. Those seeking to access the microdata must submit a research plan, and final approval for access rests with the Commissioner of BLS. Proposed projects must have a well-defined research question of scientific merit that is of a purely statistical nature. More information about obtaining access to SOII microdata can be found at the BLS restricted data access webpage.

Publications

Articles and detailed tables containing both national and state data are published regularly in the BLS online publications Beyond the Numbers (BTN), Monthly Labor Review (MLR), The Economics Daily (TED), Spotlight on Statistics, and other publications. There are also some articles in the no-longer-published Compensation and Working Conditions that are accessible on the BLS website through the MLR archive.

You can find a list of some of the articles, as well as special compendiums with both SOII and Census of Fatal Occupational Injuries (CFOI) data, on the IIF publications page.

The IIF program also periodically publishes fact sheets relating the data to current events.

Data are also available at https://www.bls.gov/iif/oshcont1.htm and are published in private safety and trade journals. In addition, state data through 1987 are available on microfiche from the National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. A list of states (including telephone numbers) that can provide more current state estimates is available from the BLS Office of Safety, Health, and Working Conditions at (202) 691-6170, or the list can be accessed online at https://www.bls.gov/iif/state-data.htm.

Data correction

If an error is found in a published SOII data product (news release, data table, etc.), the product is either corrected and republished or incorrect data products are removed. Corrected products will clearly note that a correction was made. A record of the error is added to the list of BLS errata, and data users who have signed up to receive notifications from the IIF program are alerted via email. All relevant documentation is updated, and, if appropriate, new webpages are created to document the error and its correction.

Publication guidelines for SOII estimates

Nonfatal occupational injury and illness estimates were published for more than 1,100 NAICS industries (including aggregates) in 2014 including select industries within state and local government, which were published for the first time for the 2008 survey year. Data for the SOII are collected under a strict pledge of confidentiality that these data will be used solely for statistical purposes and will not be disclosed for other purposes. The number of publishable industries may vary from year to year, depending on the number of industries that fail to meet publication guidelines. Industry estimates may not be published if one of the following situations exists:

Publication might disclose confidential information.
The relative standard error of the estimate for days away from work, job transfer, or restriction cases for the industry exceeds a specified limit.
The benchmark factor for the industry falls outside an acceptable range.

Data for an unpublished industry are included in the total for the aggregate industry level of which it is a part. Also, selected estimates are suppressed within publishable industries if the relative standard error for the estimate exceeds a specified limit.

For case circumstances and worker characteristics, estimates are rounded to the nearest 10 and are suppressed if one of the following situations occurred:

The number of cases is fewer than 15.
The number of cases is 15 or greater and the relative standard error for the estimate exceeds a specified limit or if the estimate does not meet confidentiality standards.

Uses and limitations of SOII estimates

National and state policymakers use SOII estimates as an indicator of the magnitude of and trends in occupational safety and health issues. The Occupational Safety and Health Administration (OSHA) uses the statistics to help measure the effectiveness of its enforcement and outreach programs in reducing work-related injuries and illnesses. Private industry labor and management parties use SOII estimates in evaluating safety programs. Other users include insurance carriers involved in workers’ compensation, industrial hygienists, manufacturers of safety equipment, researchers, and others concerned with job safety and health.

Many factors can influence counts and rates of injuries and illnesses in a given reference period. These include not only the injury and illness experiences but also employers’ understanding of which cases are work-related under current OSHA recordkeeping guidelines. The number of injuries and illnesses reported also can be affected by changes in the level of economic activity, working conditions and work practices, worker experience and training, and the number of hours worked.

Each year, SOII measures the number of new work-related illness cases that are recognized and reported. However, some conditions, such as long-term latent illnesses caused by exposure to carcinogens, often are difficult to associate with the workplace and are not adequately recognized and reported. These therefore are believed to be understated in the SOII. In contrast, most of the reported new illnesses are those which are easier to directly link to workplace activity (such as contact dermatitis or carpal tunnel syndrome).

SOII estimates have recently come under increased criticism for undercounting all types of workplace injuries and illness, not just long-term latent illnesses. In 2009, BLS received Congressional funding to investigate this issue and initiated an ongoing SOII data quality research program. Like the academic research studies that preceded it, initial BLS research matching SOII data to eligible workers’ compensation records in several states points to an undercount of injuries and illnesses by SOII. The overall magnitude of the undercount has proven more difficult to pinpoint. Much of the subsequent research shifted to interviews with employers to learn more about their injury and illness recordkeeping practices and their understanding of OSHA injury and illness recordkeeping rules. Initial results of these interviews point to employer misunderstanding of OSHA recordkeeping rules that could at least partially explain the undercount observed in both academic and early BLS-funded studies. Recent undercount research has shifted focus into studying the feasibility of collecting injury and illness data directly from workers. Data collected from workers would avoid errors associated with employer misreporting and may also be a way to bypass filters to workplace injury and illness reporting that can cause both workers and employers not to report eligible cases. More information on the SOII data quality research program can be found at https://www.bls.gov/iif/data-quality-research/data-quality.htm.

Data quality research

BLS is conducting ongoing research to investigate the completeness of the injury and illness counts from SOII. The purpose of this research is to better understand the reasons for an undercount of occupational injuries and illnesses reported by SOII and to identify ways to improve the collection of occupational injury and illness data. More information can be found on our Data quality research page.

Last Modified Date: November 08, 2023