Symptoms of Heat Stress
Heat stress manifests through a variety of symptoms, which can range from mild discomfort to severe medical emergencies. Key symptoms to watch for include:
- Dizziness and Fainting: Workers may feel lightheaded or dizzy, which can lead to fainting. This is often a result of the body's attempt to cool down by diverting blood flow to the skin.
- Fatigue: Excessive tiredness can occur as the body expends more energy to cool itself. Workers may find it difficult to maintain their usual productivity levels.
- Nausea and Vomiting: These symptoms can indicate that the body is struggling to cope with heat, potentially leading to more severe conditions if not addressed.
- Heat Cramps: Painful muscle cramps, usually in the legs or abdomen, can result from the loss of salts and electrolytes through sweating.
- Heat Exhaustion: Characterized by heavy sweating, weakness, cold, pale and clammy skin, a fast but weak pulse, and possible fainting. If untreated, it can lead to heatstroke.
- Heatstroke: A severe condition that requires immediate medical attention. Symptoms include a high body temperature (above 103°F), hot, red, dry or moist skin, rapid and strong pulse, and possible unconsciousness.
Recognizing the environmental factors that contribute to heat stress is equally important. High temperatures and humidity levels are primary contributors, but several other conditions can exacerbate the risk:
- High Ambient Temperatures: Prolonged exposure to temperatures above 90°F significantly increases the risk of heat stress, especially when combined with physical labor.
- High Humidity: When humidity levels are high, sweat does not evaporate as efficiently, reducing the body's ability to cool itself.
- Direct Sun Exposure: Working under direct sunlight increases the body's heat load. Providing shade or scheduling tasks to avoid peak sun hours can mitigate this risk.
- Poor Ventilation: Enclosed spaces with inadequate ventilation can trap heat and humidity, creating a stifling environment.
- Lack of Rest Breaks: Continuous work without sufficient breaks in a cooler environment can lead to the accumulation of heat stress.
- Inappropriate Clothing: Wearing heavy or non-breathable clothing can impede the body's ability to dissipate heat.
Preventing heat stress involves a combination of administrative controls, engineering controls, and personal protective equipment (PPE):
- Hydration: Ensure workers have access to cool drinking water and encourage regular hydration.
- Rest Breaks: Implement scheduled breaks in shaded or air-conditioned areas to allow workers to cool down.
- Work Schedule: Adjust work schedules to avoid peak heat periods. Rotating tasks among workers can also help reduce individual exposure.
- Training: Educate workers about the signs and symptoms of heat stress and the importance of reporting any issues promptly.
- Clothing: Encourage the use of lightweight, breathable clothing and PPE designed to minimize heat retention.
- Monitoring: Use tools like wet bulb globe temperature (WBGT) meters to assess the heat stress risk in the workplace and adjust work practices accordingly.
Find out more about Heat Stress Monitors
__________
Sources
- OSHA - Heat Stress Overview OSHA
- NIOSH - Heat Stress Management NIOSH
- ACGIH - Heat Stress and Strain TLVs ACGIH