Today, the Centers for Disease Control and Prevention released new data on heat deaths among U.S. workers, underscoring the often-tragic consequences that result when employers fail to take relatively simple and low-cost preventive actions.
Published in today’s issue of CDC’s Morbidity and Mortality Weekly Report (MMWR), researchers reviewed two years worth of OSHA enforcement cases that were investigated under its general charge to uphold safe and healthy workplaces. (OSHA investigates workplace heat illness and death via the “general duty clause” of the Occupational Safety and Health Act of 1970, as the agency has yet to issue a specific heat standard.) During 2012–2013, the study found 20 cases of heat illness or death among 18 private employers and two federal agencies. In 13 of those cases, heat exposure caused a worker’s death. In the remaining seven OSHA cases, two or more workers experienced heat illness symptoms. Workers at particular risk of overheating, which can also damage a person’s brain and other vital organs, are those who work outdoors in industries such as agriculture, construction, landscaping and transportation.
In the MMWR study, most of the people worked outdoors, though seven of the cases happened indoors in work settings with a powerful heat source, such as laundry equipment or combustion engines. All of the affected workers performed heavy or moderate work. Nine of the documented deaths happened in the first three days of being on the job and four deaths occurred on the worker’s very first day. Those findings, in particular, underscore the importance of instituting workplace procedures that let workers slowly acclimate to heat. Unfortunately, the OSHA data shows that heat illness prevention programs were either incomplete or entirely absent from the workplaces in question. In addition, OSHA inspectors found no workplace provision for the acclimatization of new workers. (According to the study: “Acclimatization is the result of beneficial physiologic adaptations (e.g., increased sweating efficiency and stabilization of circulation) that occur after gradually increased exposure to heat or a hot environment.”)
Researchers also found that 13 of the employers did not have a routine way of identifying heat risk, seven employers failed to provide enough water and 13 failed to provide enough shaded rest areas. Only one of the employers implemented work-rest cycles. All of the OSHA-documented cases of heat illness and death happened on days with a heat index between 84 degrees and up to nearly 106 degrees. Overall, failure to give workers time to acclimate was “most clearly” associated with heat death. Study authors Sheila Arbury, Brenda Jacklitsch, Opeyemi Farquah, Michael Hodgson, Glenn Lamson, Heather Martin and Audrey Profitt write:
Employers need to provide time to acclimatize for workers absent from the job for more than a few days, new employees, and those working outdoors during an extreme heat event or heat wave. Employers must ensure that all workers acclimatize to hot environments by gradually increasing duration of work in the hot environment. In addition, health care providers should be aware of the loss of acclimatization in their patients who have been out of work for a week or more and counsel them that they will need time to regain acclimatization once they return to their job.
Every year, millions of people are exposed to the serious risks of extreme heat, however outdoor workers make up the largest percentage of people who suffer from heat-related illness. The MMWR study noted that in Maricopa County, Arizona, between 2002 and 2009, construction and agricultural workers accounted for 35 percent of all heat deaths among men. And in North Carolina between 2008 and 2010, heat illness was the number-one reason workers landed in the emergency room.
For more on preventing heat illness among workers, download this infosheet from CDC and the National Institute of Occupational Safety and Health, or visit OSHA’s Heat Illness Prevention Campaign. Read the full MMWR study here.
Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.