Developing Effective Protocols to Protect Farmworkers from Heat Stress and Illness While Working in Polytunnels

Area of Science:

• Agricultural science
• Occupational health
• Environmental science

Background:

• Polytunnels (hoop houses) are increasingly used for year-round crop production.
• Farmworkers within polytunnels face elevated risks of heat-related illness due to higher temperatures and humidity.
• Limited data exists on heat stress mitigation for workers in California's Central Coast polytunnels.

Purpose of the Study:

• To quantify polytunnel area and estimate worker populations in California's Central Coast.
• To assess existing heat management and worker protection practices within these environments.
• To develop evidence-based recommendations for enhancing farmworker safety in polytunnels.

Main Methods:

• Satellite imagery analysis to determine polytunnel coverage.
• Crop production data to estimate agricultural worker numbers.
• Key informant interviews to evaluate current safety protocols.

Main Results:

• Over 5,000 hectares of polytunnels were identified, potentially exposing an estimated 46,000 farmworkers.
• Current practices generally align with OSHA regulations, but may be insufficient for unique polytunnel conditions.
• Wet bulb globe temperature is a more precise indicator of heat stress than temperature alone.

Conclusions:

• Farmworkers in polytunnels are at significant risk of heat-related illness.
• Existing safety measures may require enhancement to address polytunnel-specific environmental hazards.
• Implementing a hierarchy of controls is recommended to reduce heat stress risks for farmworkers.