Rising Risks: Heat-related Fatalities and Hospitalizations in the U.S. Upstream Oil and Gas Extraction Industry

As summer temperatures rise, the threat of heat-related illness and death to oil and gas workers increases.

• By Bradley King
• Aug 01, 2024

Oil and gas extraction (OGE) workers have the potential to be exposed to extreme heat conditions. Particularly in areas where OGE activities are extensive such as southern or western Texas (i.e., the Eagle Ford Shale and the Permian Basin, respectively), summer temperatures can routinely exceed 100 degrees Fahrenheit (°F). These workers perform physically demanding outdoor work over 12 or more hours per 24-hour shift, increasing the potential for exposure to heat stress conditions. 

Studying Heat Risks in OGE Workers

A recent study by investigators at the National Institute for Occupational Safety and Health (NIOSH) highlighted the toll that heat stress and a combination of related factors have on the health and safety of workers in the upstream OGE industry in the United States. In the study, NIOSH scientists analyzed two databases to learn more about serious heat-related illnesses experienced by OGE workers and factors that may increase the risk for such illness. 

To identify potential heat-related fatalities, the scientists used the NIOSH Fatalities in Oil and Gas Extraction (FOG) Database. This database collects detailed information about OGE worker fatalities from the years 2014–2019. Data on these fatalities are pulled from Occupational Safety and Health Administration (OSHA) reports, autopsy and medical reports, media coverage, and other sources. Cases of environmental exposures in which ‘heat’, ‘hot’, and ‘temperature’ were mentioned were identified and reviewed for evidence that the fatalities were caused by heat. If available, data extracted included worker demographics, recorded ambient and core body temperatures, physical activities preceding the fatality, heat-related symptoms, new employee status, evidence of heat-stress training, and other occupational risk factors such as positive post-mortem drug results from toxicology screens. 

In addition to the NIOSH FOG database, the scientists also used the OSHA Severe Injury Report Database to examine trends among worker hospitalizations due to heat. The database includes information on severe work-related injuries reported to OSHA, including incident descriptions (e.g., date, location, North American Industrial Classification System [NAICS] code, and the source and nature of the injury). Cases of hospitalization due to temperature extremes or environmental heat among OGE company types were identified for the timeframe beginning in January 2015 through May 2021.  

Analyzing the Data: Fatalities and Hospitalizations

Among cases in the FOG database, nine heat-related fatalities were identified. Symptoms experienced by these individuals prior to their death included loss of consciousness, mental status changes, seizures, delirium, and/or agitation. Of these nine fatalities,

• nine (100 percent) were male ranging in age from 19-67 years, with most under the age of 50,

• nine (100 percent) were well servicing workers (NAICS 213112),

• eight (89 percent) occurred in Texas (the state with the majority of oil and gas activity during 2014-2019),

• eight (89 percent) had moderate, heavy, or very heavy physical activity in an environment with temperatures greater than 90°F,

• six (67 percent) occurred in June and July,

• five (56 percent) had positive post-mortem drug tests for amphetamines and/or methamphetamines,

• five (56 percent) had a body mass index (BMI) above 30.0 (obese), with one additional case having a BMI between 25.0 and 29.9 (overweight),

• five (56 percent) showed evidence of lack of heat stress training,

• five (56 percent) worked at the company for less than two weeks, with three (33 percent) dying on their first day of work, and

• four (44 percent) had evidence of underlying hypertension or arteriosclerotic cardiovascular disease.

Among cases in the OSHA Severe Injury Report Database, 50 workers were identified who were hospitalized with serious heat-related illness. Of these 50 cases,

• 35 (70 percent) were well servicing workers (NAICS 213112),

• 30 (60 percent) occurred in Texas,

• 29 (56 percent) occurred in June and July,

• 14 (28 percent) reported body aches/cramps/pain,

• eight (16 percent) reported feeling ill or sick,

• six (12 percent) reported nausea/vomiting, and

• four (8 percent) reported lightheadedness or dizziness.

Implementing Prevention Measures

In reviewing these cases of heat-related fatalities and hospitalizations, several major risk factors were identified, including lack of appropriate acclimatization and heat stress training implemented by the employers. More than 50 percent of the fatalities occurred among workers at their company for less than two weeks. One-third of the fatalities occurred to workers on the first day of work. Evidence suggests that the failure to recognize or appropriately respond to signs and symptoms of heat stress was a factor in more than 50 percent of the fatalities. While the absence of acclimatization and training protocols for new workers have been previously identified as risk factors of heat-related illness resulting in deaths among workers, these data highlight the importance of such programs in this industry. 

Substance use was associated with more than 50 percent of the fatalities identified. Amphetamines/methamphetamine use can induce or amplify hyperthermia. However, it is unknown if the workers were using these substances illicitly or if the amphetamines were prescribed by a medical practitioner as part of a treatment for a medical condition (e.g., attention-deficit/hyperactivity disorder [ADHD], narcolepsy). 

Lastly, additional important risk factors identified were personal: the presence of obesity and underlying cardiovascular disease or hypertension among the worker fatalities. High environmental temperatures can put increased burden and demand on the cardiovascular system. For OGE workers with pre-existing cardiovascular disease and obesity, such an additional burden can be especially dangerous.

Addressing these risk factors are key to preventing future heat-related illness, hospitalizations, and fatalities in this industry. While eliminating work in high temperature environments in the OGE industry may be impossible, employers and health and safety professionals can implement effective programs to address many of the risk factors identified in the analysis. Adequate and comprehensive heat stress training and management programs are essential. Such programs can emphasize the importance of recognizing early signs and symptoms of heat-related illness and the proper response once identified (e.g., notification of supervisors, appropriate management response, provision of first aid as needed, and seeking of immediate medical help). 

Training can also include the importance of understanding and recognizing hydration status and the risk of substance use (including amphetamines prescribed by clinicians). Training and permitting workers to self-pace during work activities in which they are under high thermal stress can be a part of a holistic approach to managing heat exposures, although self-pacing alone may not be sufficient. Implementation of a buddy system to help identify early signs in one or more fellow workers and to provide first aid and emergency cooling can also be incorporated into a comprehensive heat stress training and management program.

NIOSH has developed recommendations for acclimatizing new and returning workers to work conditions in the heat. The high number of fatalities identified among workers new to their company (and likely not acclimatized to the work and/or environmental temperatures) indicates the need to implement a program that allows workers to appropriately develop heat tolerance. Because of factors identified including substance use, obesity, and underlying cardiovascular disease, the utilization of a medical monitoring program is vital. Such a program can include an occupational medical professional engaging with the worker to:

• conduct a pre-placement medical evaluation that includes a comprehensive work and medical history, physical examination, and obesity assessment;

• identify workers who may be more susceptible to heat stress due to medical illness such as high blood pressure, diabetes, or cardiovascular disease;

• assess the workers’ health before and during physically demanding work in a hot environment;

• document medications workers take that may exacerbate thermal stress conditions (e.g., amphetamines) or that can exacerbate dehydration (e.g., diuretics) and advise them of the higher risk such medications may pose related to working in hot environments; and

• if substances like amphetamines are being used by workers illicitly, implementing a workplace supportive recovery program to prevent substance misuse and encourage recovery might also help prevent heat-related fatalities. 

Heat exposure can result in physiological responses that contribute to increased workplace hazards, altered behavior, or reduced use or improper wearing of personal protective equipment (PPE). Therefore, it is likely that the number of illnesses, injuries, and fatalities related to heat-exposure in this and other industries are undercounted. Even though the databases used in this study have limitations, this analysis of heat-related illness and fatalities identified several important risk factors for workers in this industry. Because hot outdoor working conditions may become more common and extreme due to a changing climate, it is important that employers and occupational health and safety professionals understand these risks factors and establish timely and appropriate controls to address them.

This article originally appeared in the July/August 2024 issue of Occupational Health & Safety.