New workers are vulnerable to heat-related illness because they have not acclimatized to working in the heat. Acclimatization is a physiological process that occurs when exposure to heat takes place gradually over an extended period. Once acclimatization is achieved, working in the heat results in production of a more dilute sweat (lower salt content) and less of an increase in heart rate and body temperature, reducing the risk of heat-related illness.  

One approach to achieving acclimatization is to limit occupational heat exposure to one-third of the workday during the first and second days, one-half of the workday during the third and fourth days, and two-thirds of the workday during the fifth and sixth days.

Photo credit: California Farm Bureau Federation

Additional Strategies For Worker Heat Acclimatization 

• Schedule new workers for shorter time periods in the heat, separated with frequent break periods. 
• Train new workers about heat exposure, symptoms of heat-related illness, and the importance of rest and hydrating with water even during non-work hours. 
• Monitor new workers closely for any symptoms of heat-related illness. 
• Use a system where new workers do not work alone. 
• If new workers talk about or show any symptoms, allow them to stop working. Administer first aid. Never leave someone alone who is experiencing heat stress symptoms. 

These increased precautions should last for 1–2 weeks. After that time, new workers should be acclimatized to the heat and can safely work a normal schedule. The acclimatization procedure should be repeated if a person misses workdays after days off due to illness, vacation, or other reasons for missing one week or more of job duties. For more information on acclimatization, check out this resource from NIOSH. 

The Rutgers NJAES factsheet on “Preventing Heat Stress in Agriculture” has been updated and is now available at https://njaes.rutgers.edu/FS747/. The factsheet provides basic knowledge about heat stress, first-aid treatment, and preventative measures that are important to both agricultural employers and workers. As the temperatures warm up, it’s time to get prepared for working in the heat!

The body uses water to help dissipate heat through sweat and evaporation of sweat. Water lost as sweat must be replaced through water consumption to help the body maintain temperature regulation. During moderate activity, the CDC recommends drinking at least 1 cup of water every 15-20 minutes to replace water lost through sweat.  

Sports drinks are likely unnecessary to replenish the body’s electrolytes when adequate hydration is combined with regular meals.  However, sports drinks may be beneficial to help balance the body’s water and electrolytes when tasks conducted under hot temperatures result in prolonged sweating over several hours.  

Limit consumption of energy drinks, alcohol, and caffeine-containing beverages such as coffee, tea, and soda. These beverages can contribute to dehydration, increasing the risk of heat illness.  

Staying hydrated starts before work then continues throughout the day and after work. Attention to personal hydration decreases the risk of heat illness and other risks associated with chronic dehydration, such as kidney stones. 

The New Jersey Legislature is currently reviewing identical bills (A3521/S2422) which would establish an occupational heat stress standard and “Occupational Heat-Related Illness and Injury Prevention Program” under the NJ Department of Labor and Workforce Development. As we monitor the progress of these bills, the Farm Health and Safety Working Group of Rutgers Cooperative Extension has launched an educational program on heat stress mitigation in agriculture which includes weekly “Beat the Heat” articles published in the Rutgers Plant and Pest Advisory E-Newsletter, an update to the Rutgers factsheet “Preventing Heat Stress in Agriculture” and a webinar series.

USDA photo by Preston Keres. 

In partnership with New Jersey Farm Bureau, we invite you to join us for a two-part webinar series titled “Don’t Sweat Heat Stress in Agriculture”.

• Wednesday, June 5 from 7:00-8:00 PM
  • An introduction to heat stress issues in agriculture. We will also share tools farmers can use to evaluate heat risk and recommended resources for guidance on heat stress prevention.
• Wednesday, June 12 from 7:00-8:00 PM
  • An overview on signs of heat stress and corresponding first aid, as well as strategies for heat stress prevention. A panel of farmers will discuss their currently used strategies for employee management during periods of high heat.

You must register to attend these webinars by visiting https://go.rutgers.edu/heat-stress-in-ag. 

Questions? Contact Kate Brown, County ANR Agent with RCE-Somerset County, at 908-526-6293 x4 or kbrown@njaes.rutgers.edu.

Heat safety tool phone app created by OSHA and NIOSH.

As the weather warms up, prepare yourself to evaluate the heat risk for outdoor tasks. We often use a weather application on our phone to check the daily high and low temperature, but air temperature alone is not sufficient to evaluate heat risk. Heat index is a more appropriate measurement because it combines the effects of air temperature and humidity to indicate the level of discomfort felt by the average person. 

One easy way to check the heat index is the Heat Safety Tool phone app (see photo) developed by the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH). The app calculates heat index at your specific site and displays the risk level to outdoor workers. It also provides insight into protective measures for the given risk level. This mobile phone app is available for both Android and iPhone. 

A similar, web-based tool is the HeatRisk website created by the U.S. Centers for Disease Control and Prevention (CDC). The HeatRisk homepage has a color-coded map to indicate today’s heat risk (no risk to extreme risk) for each county in the U.S. You can also enter your zip code to get the daily and 5-day forecasted heat risk for your site plus corresponding actions to reduce heat-related health risks. 

 Stay tuned for weekly posts on how beat the heat this summer!