On August 8, 2013, the Occupational Safety and Health Administration (OSHA) published a report in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report (Vol. 63. No. 31) related to the causes of heat illness and death among workers in the United States.  The report is the result of a OSHA’s Heat Illness Workgroup’s review of 20 federal enforcement cases in 2012-2013 where employers were issued citations under Section 5(a)(1) of the Occupational Safety and Health Act, better known as the General Duty Clause, for heat-related deaths and illness among workers.

In the 20 cases involving heat illness and death among workers, OSHA found that most of the affected workers worked outdoors, with 13 out of 20 working outdoors. OSHA also found that all employees performed either heavy or moderate work.  OSHA’s review revealed that nine out of the 13 deaths occurred as a result of exposure to heat during the first 3 days of working on the job, with four of those deaths occurring on the worker’s first day in a new job.  In addition, many employers were found to have no heat illness prevention program or lacked many of the basic requirements, such as water management, shaded rest areas, and work-rest cycles.

The report indicates that a failure to provide acclimatization of new employees or employees who are returning to work from an absence of more than a week was “the most common deficiency and the factor most clearly associated with death.”  As a result, OSHA concluded that employers need to provide time to acclimatize new employees, workers who are absent from the job for more than a few days, and those working outdoors during an extreme heat wave as part of a successful heat illness prevention program.

OSHA recommended that new workers and all workers returning from an absence of more than a week should begin with 20% of the usual duration of work in the hot environment on the first day, increasing the duration of work by no more than 20% each subsequent day.  OSHA also recommended that during heat waves or rapid temperature increases, employers should acclimatize workers, even experienced ones, by reducing their duration of work on the first day of excessive heat by 50% and slowly increasing the duration of work on the second and third days.