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Handbook of Methods Survey of Occupational Injuries and Illnesses History

Survey of Occupational Injuries and Illnesses: History

Data on safety and health conditions for workers on the job have been produced by the Bureau of Labor Statistics (BLS) since before World War I. The first safety and health report issued by BLS summarized industrial accidents in the iron and steel industries in 1912, presenting information on the frequency and severity of injuries, the occupation of the injured workers, and the nature of their injuries.1

Work-related illnesses also were the subject of BLS studies conducted in the early 1900s, such as the pioneering research on lead poisoning in the workplace done by Dr. Alice Hamilton.2

The current BLS Survey of Occupational Injuries and Illnesses (SOII) evolved from annual BLS surveys first conducted in the 1940s, when injury recordkeeping standards became sufficiently uniform to permit the collection of nationwide work injury data. Spanning three decades, those nationwide surveys proved useful in measuring and monitoring injury frequency and severity, but they had two major limitations. First, the survey data were compiled from and represented only employers who volunteered to record and report work injuries. Second, work injuries were limited to those that resulted in death, permanent impairment, or temporary disability, defined as unable to perform regular job duties beyond the day of injury. Thus, survey estimates excluded many employers and, by definition, numerous cases that required medical treatment (beyond first aid) or restricted work duties but did not result in days away from work.

These and other limitations were addressed in a landmark piece of safety legislation passed by the U.S. Congress: the Occupational Safety and Health Act of 1970 (OSH Act). Under the OSH Act Congress delegated the responsibility for developing a comprehensive statistical system covering work-related injuries, illnesses, and fatalities in private industry to the BLS. The separation of responsibilities at the national level between data collection (BLS), regulatory action (OSHA), and safety and health research (CDC/NIOSH) was the original vision of the OSH Act and still remains our primary operating principle. Our data providers and stakeholders rely on BLS data being compiled without bias, without regulatory retribution, or without the possibility of confidentially-collected information being released. Since OSHA and NIOSH use our data for regulatory and formal advisory purposes, it is important that we remain separate from them to maintain impartiality. The 1970 act and its implementing regulations required that most private industry employers regularly maintain records and prepare reports on work-related injuries and illnesses, which include all disabling, serious, or significant injuries and illnesses, whether or not involving time away from work.3

In 1972, the BLS, in cooperation with many state governments, designed the Survey of Occupational Injuries and Illnesses (SOII) to estimate the number and frequency of work-related injuries and illnesses by detailed industry for the nation and for states participating in the SOII. The data published from the survey continues to be a great resource to the safety and health community when deciding how to allocate prevention resources among diverse industries, across which, workers’ risks of injury and illness vary widely.

As originally designed, however, the SOII had limitations. Although the survey identified industries with dangerous work settings, it failed to produce a reliable count of workplace fatalities. Also, the SOII shed little light on worker demographics or the circumstances of an injury or illness. For example, the survey did not ask about the manner in which an incident occurred and which occupations were involved.

In 1987, a congressionally funded National Academy of Sciences (NAS) study recommended that these deficiencies be corrected by collecting detailed data on severe, nonfatal occupational injuries and illnesses reported in the SOII and by compiling complete accounts of occupational fatalities from administrative records, such as death certificates and workers’ compensation reports.4 This critical review of the SOII provided the impetus for the redesign of the SOII and the creation of the Census of Fatal Occupational Injuries (CFOI).

Some of the NAS recommendations suggested using multiple data sources such as death certificates and workers’ compensation reports to identify and profile fatal work injuries for all workers. More specifically, the Keystone Dialogue Group recommended the development of a method for counting work-related fatalities, stating that the "development of an accepted count of workplace deaths should mute controversy on this issue stemming from the variety of estimates coming from different sources."5 In this regard, fatality estimates made by different organizations at that time varied greatly from 3,000 to 11,000 deaths nationally per year.6

The CFOI approach to compiling data on fatal work injuries was initially tested in a BLS cooperative effort with the Texas Department of Health during 1988. That study, which collected fatality data retrospectively for 1986, highlighted the need for multiple data sources and the feasibility of matching fatalities and their circumstances across those sources.7 This approach was tested again in Texas and Colorado in 1990, with results confirming that the same kind of data could be obtained from multiple data sources on a current basis.8 The CFOI was initially implemented in 32 states and New York City in 1991 and expanded to cover all 50 states and the District of Columbia in 1992. As of 2011, the U.S. territories Puerto Rico, Virgin Islands, Guam, and America Samoa are also included.

Several changes that have had significant impacts on data from the BLS safety and health statistics program, including updated recordkeeping requirements, new industry and occupation classification systems, and changes in race and ethnicity standards, are discussed in the concepts section.


The following timeline illustrates key developments in identifying and quantifying the annual number of work-related injuries, illnesses, and fatalities.  Most changes were milestones in program development, such as the Occupational Safety and Health Act of 1970 and the National Academy of Sciences’ National Research Council report, while others were fundamentally philosophical, such as the New Deal’s new attitudes toward labor law and regulation.

Hover over the red dot to see historical information.

Key developments

  • 1894: BLS begins publishing extensively on new developments in state and foreign social legislation and practices, including accident prevention and workers' compensation. In the years preceding World War I, BLS begins to give special attention to industrial accidents and occupational diseases.
  • 1912: BLS issues its first annual report on injury rates in the iron and steel industry. A few years later, cooperative arrangements with Massachusetts, New York, and Ohio are established for reporting industrial accidents; additional states later join the program.
  • 1926: BLS introduces an annual survey tracking the frequency and severity of industrial injuries for several manufacturing industries using data compiled from state records, as well as reports from establishments in targeted industries. By 1930, BLS data covered a quarter of the workforce in some 30 manufacturing industries.
  • 1939: Occupational fatality data are added to the survey.
  • WWII (1941-45): BLS publishes monthly injury data for industries of particular wartime importance. After the war, BLS adds more industries; by 1966, more than 650 industries were included.
  • 1970: The Occupational Safety and Health Act of 1970 instituted common definitions and recordkeeping standards and required employers to maintain accurate workplace injury and illness records.
  • 1974: Data from SOII (summary) are first published, for survey year 1972.
  • 1987: The National Academy of Sciences’ National Research Council completes a study that leads to a substantial redesign of the occupational injury, illness, and fatalities statistical program.

(Years below indicate the year of data the change started)  

  • 1992: BLS restructures the survey to include data on characteristics of injured or ill workers and circumstances of the specific nonfatal injury or illness involving lost workday cases and launches a census to capture all fatal occupational injuries. (Modern CFOI and SOII program started)
  • 1992: BOC system is used to classify occupation, SIC to classify industry, and original OIICS to code the case characteristics of injuries illnesses and fatalities.
  • 1994: CFOI begins publishing a preliminary report, followed by a revised and final report of occupational fatalities.
  • 1999: CFOI begins collecting and publishing MSA data. (See the CFOI definitions page and the concepts section for more information.)
  • Early 2000s: BLS begins to provide a variety of web-based tools to facilitate reporting and data dissemination.
  • 2001: CFOI begins collecting data on birthplace. (See the CFOI definitions page for more information.)
  • 2002: OSHA recordkeeping changes result in SOII series break.
  • 2003: SOII and CFOI series break, BLS moves to the Standard Occupation Classification (SOC) system, 2000 edition to code occupations and the North American Industrial Classification System (NAICS), 2002 edition to code industry.
  • 2008: SOII begins publishing national estimates for state and local government.
  • 2009: SOII and CFOI adopt NAICS 2007 edition, not resulting in a series break.
  • 2011: SOII and CFOI series break, BLS moves to the Occupational Injury and Illness Classification (OIICS) 2.01 to code case characteristics. BLS also adopts SOC 2010 edition definitions. CFOI begins collecting and publishing data on contracted workers. (See the CFOI definitions page and concepts section for more information.)
  • 2014: SOII and CFOI adopt NAICS 2012 edition. This does not result in a series break for CFOI or SOII—Case and Demographics, but does result in a series break for SOII—Annual Summary.
  • 2015: CFOI discontinues issuing a preliminary data release, and began publishing a single final data release in December, 4 months earlier than in previous years).
  • 2019: SOII and CFOI adopt the NAICS 2017 and SOC 2018 systems. This does not result in a series break for CFOI or SOII.


More information on the history of the Injuries, Illnesses, and Fatalities (IIF) program can be found on the IIF History homepage. For more information on the historical development of occupational injury, illness and fatality data, see the articles “Improvements in the BLS safety and health statistical system,” “Occupational safety and health statistics: new data for a new century,” “A Century-Long Quest for Meaningful and Accurate Occupational Injury and Illness Statistics,” and “The quest for meaningful and accurate occupational health and safety statistics”. For more information on the OSHA record keeping changes see the article “Occupational injury and illness: new recordkeeping requirements”.

1 The Safety Movement in the Iron and Steel Industry, Bulletin 234 (Bureau of Labor Statistics, 1918).
2 The White-Lead Industry in the United States, Bulletin 95 (Bureau of Labor, 1911).
3 See section 24(a) of the Occupational Safety and Health Act of 1970 (Public Law 91–596).
4 See E.S. Pollack and D.F. Keimig, eds., Counting Injuries and Illnesses in the Workplace: Proposals for a Better System (Washington, National Research Council, National Academy Press, 1987), pp. 103–06.
5 See the Keystone Center’s final report, "Keystone National Policy Dialogue on Work-Related Illness and Injury Recordkeeping," (Keystone, CO, January 1989), pp. 47. For an account of various attempts to count fatalities at work, see Dino Drudi, "The evolution of occupational fatality statistics in the United States," Compensation and Working Conditions, July 1995.
6 See BLS Survey of Occupational Injuries and Illnesses (1972–91); the National Safety Council Accidents Facts; and the National Institute for Occupational Safety and Health’s National Traumatic Occupational Fatality Study A Decade of Surveillance, 1980–1989.
7 See Janice Windau and Donna Goodrich, "Testing a census approach to compiling data on fatal work injuries," Monthly Labor Review, December 1990, pp. 47–49. The study also found that, for verification purposes, timeliness is important in maximizing respondents’ recall and in reducing the number of those failing to respond because they have relocated.
8 See Guy Toscano and Janice Windau, "Further testing of a census approach to compiling data on fatal work injuries," Monthly Labor Review, October 1991, pp. 33–36.
Last Modified Date: October 30, 2020