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Injuries to International Petroleum Drilling Workers, 1988-1990

Occupationally related death rates among workers involved in oil and gas extraction activities have been higher than rates for workers from all U.S. industries combined (1). In 1991, nonfatal work-related injury (NFI) rates (2,3) for workers in the U.S. oil and gas field services industry (standard industrial classification {SIC} codes 138.1, 138.2, and 138.9) * were 49% greater than rates for all workers in private industry and tended to be more severe, with a lost-workdays rate more than 2.8-fold higher than in private industry as a whole (2). To develop improved strategies for preventing fatal injuries (FIs) and NFIs among petroleum drilling workers, the Louisiana Office of Public Health (LOPH) analyzed data on injury-related incidents in the petroleum drilling industry during 1988-1990. This report summarizes the results of this study.

The LOPH analyzed data on injury-related incidents submitted voluntarily by 347 (87%) of 398 member drilling companies to the International Association of Drilling Contractors (IADC), an international trade association that represents the oil and gas drilling industry. U.S. workers represented by the IADC are categorized by the U.S. Bureau of Labor Statistics into SIC code 138.1.

The IADC defines an NFI as any work-related event that prevents an employee from returning to his/her regular job on the next regularly scheduled workday, including FIs if they occur on the job. For each incident, data reported to IADC include 1) whether the injury was fatal, 2) the geographic location of the worksite (U.S. or non-U.S.** and on land or water), 3) employee occupation, 4) body part injured, 5) injury type (e.g., "fall," "struck by," "caught in"), 6) equipment used, 7) operation at the time of injury, and 8) location at which injury occurred on the rig. Estimates of total person-hours were made from rig count and representative rig crew data. Geographic location- and occupation-specific incidence rates were then calculated in terms of total full-time equivalents (FTEs ***) per job category and year.

Of the 5251 reports, 5218 (99%) involved NFIs (Table 1) -- representing an overall 3-year rate for NFIs of 1.2 per 100 FTEs. The rate of reported NFIs in the United States (land and water combined) was four times the rate outside the United States (2 per 100 versus 0.5 per 100 FTEs). Rates of NFI were higher on water than on land for the United States (2.5 versus 1.9; {rate ratio (RR)=1.3}) and for sites outside the United States (1.2 versus 0.2; {RR=5}). Injuries to the upper extremities (i.e., fingers, hands, or arms) accounted for the largest proportion of reported NFIs (1631 {31%}).

Thirty-three (0.6%) reports were of FIs, representing an overall 3-year rate of 7.5 per 100,000 FTEs. Combined rates for land and water were similar for U.S. and non-U.S. sites (6.5 per 100,000 and 8.3 per 100,000 FTEs, respectively). However, in both locations, FIs occurred more commonly on water than on land (19.2 versus 4.0 for U.S. sites and 20.3 versus 3.9 for non-U.S. sites, respectively). Head and neck injuries accounted for the greatest proportion (11 {33%}) of reported FIs.

Three job categories -- floormen, roustabouts, and derrickmen

  • accounted for 3883 (74%) NFI reports and 21 (64%) FI reports. Rates of reported NFIs and FIs were 4-10.5 times higher among these workers than for other workers (Table 2). Workers in these three jobs directly handle the drilling pipe. However, roustabouts are generally employed on water-based rigs only. Reported by: R Ratard, MD, L McFarland, DrPH, State Epidemiologist, Office of Public Health, Louisiana Dept of Health and Hospitals. Div of Field Epidemiology, Epidemiology Program Office, CDC.

    Editorial Note

Editorial Note: An estimated 51,393 workers are employed in oil and gas drilling operations in the United States (4). The national health objectives for the year 2000 target the reduction of deaths from FIs among mine workers (which includes oil and gas drilling workers) to no more than 21 per 100,000 FTEs (objective 10.1a) and the reduction of NFIs to 6 per 100 FTEs (objective 10.2) (5). The year 2000 objective for FIs in this group is the highest target set among all U.S. workers and reflects recognition of the high risk for FIs among mine workers. The findings in this study suggest that overall NFI and FI rates for U.S. petroleum drilling workers (SIC code 138.1) are below these objectives.

Although rates of reported FIs in this study were similar for U.S. and non-U.S. workers, rates for reported NFIs were substantially higher for workers in the United States. Potential explanations for these differences include variations in work and safety conditions, working practices, reporting requirements and procedures, laws regarding compensation for work-related injuries, and medical care.

Risk factors that contribute to hazardous working conditions on land-based and water-based drilling rigs include high rates of job change and rig transfers, the young age of the workforce (6), and type A behavior (7). The findings in this report also indicate potential specific high-risk occupations within this industry.

Safety education of workers remains an important aspect of injury prevention. Redesigning equipment and/or implementing changes in selected working practices may reduce injuries and deaths. In addition, the use of four-digit SIC-code data helps in differentiating intra-industry risks. The systematic collection of injury data by trade associations such as the IADC assists in injury-prevention efforts and is an important contribution to worker safety and health.


  1. CDC. Occupational mortality in the oil industry -- Louisiana. MMWR 1980;29:230-1.

  2. Bureau of Labor Statistics. Survey of occupational injuries and illnesses, 1991. Washington, DC: US Department of Labor, Bureau of Labor Statistics, December 1992; summary no. 92-9.

  3. National Safety Council. Work injury and illness rates, 1991. Chicago: National Safety Council, 1992:5.

  4. Bureau of Labor Statistics. Employment and wages annual averages, 1990. Washington, DC: US Department of Labor, Bureau of Labor Statistics, November 1991; bulletin no. 2393.

  5. Public Health Service. Healthy people 2000: national health promotion and disease prevention objectives. Washington, DC: US Department of Health and Human Services, Public Health Service, 1991:104-5; DHHS publication no. (PHS)91-50213.

  6. Mueller BA, Mohr DL, Rice JC, et al. Factors affecting individual injury experience among petroleum drilling workers. J Occ Med 1987;29:126-31.

  7. Cooper CL, Sutherland VL. Job stress, mental health, and accidents among offshore workers in the oil and gas extraction industries. J Occ Med 1987;29:119-25.

* U.S. Bureau of Labor Statistics or other government-compiled data for injury and illness incidence are not routinely available for some four-digit SIC categories. Analyses of 2- or 3-digit level data represent the combined experience of all constituent groups and may not accurately represent the experience of a specific subgroup. ** Sites not regulated by the U.S. Coast Guard, individual states, or the U.S. Mineral Management Service. *** One FTE = 2000 person-hours. This denominator is used to allow comparison of rates to those published by the U.S. Bureau of Labor Statistics.

Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services.

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