The first six months of  2014 were the warmest ever recorded in California. According to NOAA's National Climatic Data Center, the past six months were nearly 5º F hotter than the 20th century average and more than 1º F warmer than the previous record, which was set in 1934.

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Under normal circumstances, drought and increased temperatures are not necessarily connected, but scientists are now exploring the notion that heat can exacerbate dryness via increased evaporation and plant transpiration. Experts already acknowledge that dry conditions can exacerbate heat because when there’s little to no water to evaporate, the heat from the sun more effectively warms the air and the ground. The ridiculously resilient ridge that has prevented winter storms from dropping rain in California during recent years is caused by a system of high pressure thatalso contributes to warm weather.

Temperatures are on the rise throughout the state, easily exceeding triple-digits on a daily basis in warmer inland and southern regions. Even when air temperatures are relatively low, scientists have found that the earth and the oceans are warming beyond any previously recorded levels. Accordingly, California state officials have turned their attention to protecting outdoor workers from the dangerous and potentially lethal impacts of working in the heat during a summer that has proven to be one of extremes.


As the primary producer of several crops that require hand-harvesting and non-mechanical labor, California has more farm workers than any other state, and the state’s agriculture industry is more dependant on farmerworker labor than at any other point during the past century.

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Photo of a man hand weeding in Arvin, CA. Courtesy of  David Bacon

Outdoor laborers, particularly farm workers, are the most at risk for heat-related illnesses. A recent study among farm workers in North Carolina showed that, among those who participated in the survey, 94 percent reported working in conditions of extreme heat, of which 40 percent reported symptoms of heat illness. The data also suggested that farm laborers with authorization to work in the United States drank more water, took more breaks, and changed their work hours and work activity more than those without authorization. Authorized workers also reported a prevalence of heat injury of 31 percent versus unauthorized workers reporting 56 percent. Roughly 10 percent of farm workers have limited access to training, water, rest, or shade, however farm workers continue to have low percentages of concern about heat illness (53 percent) and low levels of comfort taking a break for water (2.5 percent). Water consumption remains extremely low, with an average frequency of 10.7 drinks per day. Current recommendations suggest drinking four times per hour (32 times per day).

Nationwide, there were 68 confirmed heat-related deaths on farms between 1992 and 2006, and the crop worker fatality rate was 20 times higher than the average civilian worker fatality rate. The heat-related average annual death rate for these crop workers was 0.39 per 100,000 workers, compared with 0.02 for all U.S. civilian workers. In California, death rates are even higher at 0.49 per 100,000 workers on average. An especially deadly heat wave in California in 2006 supported advocates’ longtime argument that seasonal temperatures and a lack of mandatory worker protections represented a predictable and deadly risk to farm workers. Heat-related illnesses and fatalities are regularly underreported, but the problem persists, with many farm workers falling ill each year and individuals dying every summer. Heat illness can persist and even worsen after work hours, especially if workers are unable to escape the heat to rest and recover, for example through air conditioning and access to cool, clean water.

Federal law requires that employers protect workers from hazards that are causing or likely to cause death or serious harm, including excessive heat. The California Division of Occupational Safety and Health (Cal/OSHA) enacted emergency heat regulations on August 22, 2005, and California’s Heat Illness Prevention Standard became permanent on July 27, 2006. The regulations were updated again in 2010 to include all outdoor places of employment whenever the temperature is 85º F or higher, and to authorize alternative procedures for shade protection where normal shade structures are unfeasible or unsafe. The 2010 amendment emphasized the importance of effective worker and manager trainings on recognizing signs of heat stress and early symptoms of heat stroke. In 2010, the Heat Illness Prevention Standard was Cal/OSHA’s second most cited standard, with nearly 1,000 violations statewide.

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Heat Illness Prevention Standards from CAL/OSHA 

Last month, Governor Brown signed SB 1360 into law, to clarify that “recovery periods” related to heat stress are like “rest periods” in that employees must be paid for the time. In response to the new law, Cal/OSHA is proposing to revise heat standards by extending and better defining “cool down rest breaks” as required and compensable time for outdoor laborers, and by clarifying previous requirements related to employers providing plenty of water and adequate shade to employees. Cal/OSHA wants drinking water and shade to be as close as “practicable” to workers and never more than 400 feet away, instead of only around the perimeters of fields.

These recent changes to California’s Heat Illness Prevention Standard imply that a break taken to cool down should be treated as a period of recovery from the early signs and stages of heat illness, rather than as a preventative measure. The changes impose certain duties u

pon employers to assess employees for symptoms of heat illness and implement measures to acclimate workers to the heat as temperatures rise.

Many agricultural workers receive piece-rate compensation. Rather than getting paid by the hour, these workers receive payment based on volume of work output: pounds or boxes harvested, number of vines tied, etc. This compensation method creates a powerful economic disincentive for taking breaks or lessening work hours due to heat. While some agribusiness groups have argued against paying for rest time or anything considered “nonproductive” work time, many farm and labor experts argue that paying employees to take breaks actually boosts productivity. Gregorio Billikopf, labor management farm advisor with the University of California, Davis, stated in a recent interview that paying for rest breaks earns employee goodwill, and the cost of doing so will be more than made up for by increased productivity and less workplace illness and injury.  


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Cal/OSHA continues with its ongoing effort to conduct public outreach and education about heat and heat-related illness among workers.