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Extreme Heat and Unprotected Workers

Public Citizen Petitions OSHA to Protect the Millions of Workers Who Labor in Dangerous Temperatures

By Mike Tanglis

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This century has witnessed extraordinary increases in temperature. Seventeen of the 18 hottest years on record have occurred since 2001. If the current trajectory continues – and there is every reason to expect it will – temperatures in the United States are going to be searing. By 2100, summers in Boston will resemble today’s summers in Miami Beach. St. Paul, Minn., will feel like Mesquite, Texas. Las Vegas will become the new Riyadh, Saudi Arabia.

The human body is a sensitive instrument. It needs to maintain an internal temperature of 98.6 Fahrenheit and can tolerate only small deviations from this temperature. Warm temperatures and physical activity can raise the body’s temperature, and put an individual at risk of severe harm. Over the past 30 years, heat has been the leading cause of weather fatalities, according to the National Weather Service.

Those who perform manual labor in hot outdoors conditions, such as agricultural and construction workers, are particularly at risk because they are subjected both to high levels of ambient heat and rising metabolic heat, which results from physical exertion.

The Occupational Safety and Health Administration (OSHA) is responsible “to assure so far as possible every working man and woman in the Nation safe and healthful working conditions.” Implicit within this charge is that OSHA must ensure that employees are not laboring under risks of bodily harm or death from excessive heat.

But workers are laboring under these risks, and OSHA has long been on notice.

In 1972, the National Institute for Occupational Safety and Health (NIOSH) recommended a standard requiring employers to protect their workers from heat stress. An OSHA advisory committee reviewed the recommendation and agreed with it.

But OSHA failed to create a heat stress standard in response. Nor did it do so in response to two subsequent NIOSH recommendations, in 1986 and 2016. Nor did it do so in response to a petition filed by Public Citizen and allies at the end of the blistering summer of 2011.

In the meantime, the toll has risen. According to figures compiled by the federal government, exposure to excessive environmental heat killed 783 U.S. workers and seriously injured 69,374 workers from 1992 through 2016.

For a long list of reasons outlined in this report, those figures greatly understate reality. OSHA acknowledged in response to Public Citizen’s 2011 petition that heat-induced “deaths are most likely underreported, and therefore the true mortality rate is likely higher.” But OSHA declined to create a protective standard at that time in part because it deemed the risk to workers to be no greater than “significant” and not meeting the threshold of “grave” to justify an emergency standard.

Subsequently, OSHA staff members have researched employer practices regarding heat, and their findings have reinforced the urgency for instituting protections. In one study, they investigated the circumstances surrounding 84 cases in which the agency had issued citations for unsafe heat conditions under the agency’s broad “general duty” clause. This portion of OSHA’s authorizingstatute permits the agency to issue penalties for unsafe conditions even if no specific standard is violated. The general duty clause carries a much higher burden of evidence than specific standards, and often is used in response to tragedies rather than to prevent them.

Twenty-three of these 84 cases reviewed in the study involved worker deaths. Remarkably, 17 of the 23 fatalities occurred in the employee’s first three days on the job, signifying the tremendous risk employees face when they are newly thrust into a high-heat environments. The same OSHA researchers found that only one of the 84 employers had a program in place to help new employees acclimatize to hot conditions. Only a handful of employers had policies to adjust work loads to account for fluctuations in the heat index. One-fifth failed to provide adequate access to water.

Three states – California, Minnesota and Washington – have established their own heat stress standards.

A look at enforcement relating to California’s law illustrates need for OSHA to create a heat-specific standard versus relying on its general duty clause. California completed 7,082 inspections resulting in at least one heat standard violation between 2013 and 2017. During that same timeframe, federal OSHA conducted only 142 inspections nationwide resulting in at least one heat-related citation under the general duty clause. This means that California conducted 50 times more inspections resulting in a violation for unsafe heat exposure practices than OSHA did nationwide between 2013 and 2017.