Every year, thousands of workers become ill from occupational heat exposure – and some cases are fatal. In the construction industry, the risk of heat stress is even more substantial because the majority of workers engage in high-exertion jobs outdoors. Research shows, in fact, that U.S. construction workers are 13 times more likely to die from a heat-related illness or injury compared to workers in other industries.
Under Occupational Safety and Health Administration (OSHA) rules, employers are responsible for providing workplaces free of known safety hazards – and this includes protecting workers from extreme heat. The fact is, heat-related illnesses can be prevented, but prevention requires employers and workers to recognize heat hazards and make appropriate modifications to the work environment, procedures, and practices.
To mitigate the risks, review the following five recommendations.
- Know the significant risk factors. Many things can contribute to increased chances of heat exposure on the job. They include:
- Temperature at the work site.
- The environment’s relative humidity.
- Personal protective equipment that could interfere with the body’s ability to sweat effectively.
- Employee workload.
- Employee age, body weight, diet, hydration, drug use, cardiovascular fitness and underlying health issues.
- Lack of worker and supervisor training on heat stress.
- Acclimate in stages. Allow new or returning workers to gradually increase workloads and take more frequent breaks as they acclimatize or build a tolerance for working in the heat. According to OSHA, lack of acclimatization is a major risk factor for heat-illness fatalities. Proper acclimatization should follow the “Rule of 20 Percent,” per OSHA guidelines. New workers and those returning from a break should begin with 20% of their usual workload on their first day, increasing by no more than 20% on each subsequent day.
- Leverage engineering controls. The goal should be to make the work environment cooler and reduce manual workloads with mechanization. For example:
- Use spot air conditioning, cooling and misting fans, and cooled seats or benches.
- Install local exhaust ventilation at points of high heat production or significant moisture generation.
- Reduce manual work with power tools or mechanical equipment like conveyors.
- Redirect radiant heat with reflective shields.
- Modify work practices. Also known as administrative controls, these measures aim to alter the work pace when heat is too high a threat to work safely. For example:
- Schedule shorter shifts for newly hired and unacclimated workers.
- Require mandatory rest breaks in air-conditioned buildings or shady areas.
- Perform labor-intensive tasks during the cooler part of the day, such as early morning or late afternoon.
- Rotate job duties among workers to avoid overexertion.
- Emphasize training. Educate all supervisors and workers about the dangers of heat stress and the types of heat-related illnesses – including heat exhaustion, heat stroke, and heat cramps – and how to recognize their signs and symptoms. All workers should also learn about prevention and first aid, including:
- Realizing the importance of proper fluid intake and electrolyte replacement.
- Recognizing signs and symptoms of heat stress.
- Understanding the benefit of a buddy system so workers can pair up and monitor each other for possible heat intolerance.
- Knowing when and how to contact emergency medical services.
For more information, consider two resources to help reduce the risks:
- Check environmental conditions before and during the workday and adjust accommodations accordingly. OSHA and the National Institute for Occupational Safety and Health’s (NIOSH) Heat Safety Tool App (in English or Spanish) gives real-time heat index information, precautionary recommendations based on weather conditions, and a guide for identifying signs and symptoms of heat-related illnesses.
- Consider using Shade. Rest., OSHA’s heat illness prevention training guide, as part of lesson plans for employees.
To learn more about the top ten causes of disabling workplace injuries overall and in construction, review our annual Liberty Mutual Workplace Safety Index.