The importance of understanding heat-related illness in schools year-round 

By Yvette Way, BA, MPH (c) and Derek G. Shendell, D.Env., MPH 

Within recent years in the U.S., some of the hottest weather has been recorded. This trend is only expected to continue and will cause an increase in incidences of heat stress for those working at schools, both indoors and outdoors.  

Heat stress is the body’s response to exposure to high temperatures or overheating. Various heat-related disorders are associated with heat stress, particularly heat stroke, heat exhaustion, fatigue, heat cramps and heat rashes. While the impact of heat can be felt by anyone, the Occupational Health and Safety Administration (OSHA) notes that a person’s age, weight, fitness level and medical conditions are among several factors that can determine a person’s sensitivity to heat.  

Recognizing the signs of heat stress can be vital in saving a person’s life. Generally, the most obvious signs of heat stress are confusion, nausea, weakness and cramping. If someone is showing any of these symptoms, get them into a cooler space and give them water and rest. In addition, immediately alert the school nurse (if one is present on campus) and the principal’s office. In extreme cases call 911. 

Exposure for those working outdoors 

Within the school system, those who work outdoors, such as physical education teachers, coaches, landscapers and other outdoor maintenance workers, are the most often exposed to high temperatures. These outside occupations leave workers exposed to the sun for long periods while working in areas such as pavement or turf, which can absorb more light, and therefore, conduct heat. While the overall temperature as locally reported may be one number, the temperature on rooftops, blacktops or fields will be much higher.  

An important step in preventing heat stress is acclimatizing to the climate. By acclimatizing to the temperature over a period of seven to 14 days, the body will be able to improve its heat tolerance. However, this should not be taken as meaning that overheating is not a risk regardless of how used to the heat an individual appears to be. 

Indoor heat stress 

While working outside can lead to higher exposure and increased risk of heat stress, those who work inside should be aware of how heat stress can negatively impact them as well. Indoor temperatures should be kept between 68 to 78 degrees Fahrenheit with humidity held between a range of 30% to 60%. 

Working in hot conditions interferes with cognitive ability, reducing academic performance in students and faculty. On a practical level—especially when classes are canceled, or schools close because of the temperature—there will be less time for students to learn and teachers will have to revise their lesson plans to compensate for the lost time.  

Most U.S. schools, including those in New Jersey, were built in the 1950s and 1960s when the climate was not as hot as it is today. The best defense that older schools have against the heat is the heating, ventilating, and air conditioning system, or HVAC.  

HVAC systems can better regulate school temperatures and keep them from overheating. But in most schools, the HVAC system has one or more issues affecting its optimal performance. According to the U.S. Government Accountability Office (USGAO), roughly 40% of public school districts need to update or replace their HVAC system.  

A 2014 report from The National Center for Education Statistics at the U.S. Department of Education (NCES) found about 30% of each assessed school’s HVAC system was in fair or poor condition. While HVAC system updates and overall ventilation with filtration improvements made from available funding during the COVID-19 pandemic may have reduced this number, much work remains to be done. 

For schools without a central HVAC system, instead relying on window-mounted air conditioning units, there may be electrical issues or spaces/gaps between the window and the air conditioner. As a result, the cold air can escape while warm air can enter.  

Despite the growing need to repair or replace HVAC systems, schools are often not provided the necessary funding. The American Society of Civil Engineers (ASCE) report card noted how state-based capital funding for schools in 2017, compared to 2008, declined over 30% (or nearly $20 billion), and 38 of 50 U.S. states cut school capital spending from 2008 to 2017. 

What can local associations do? 

Environmental hazards such as heat stress are difficult to fight, but some methods can be taken to protect yourself and others against it.  

Seek assistance from your local association worksite health and safety committee. If you don’t have one, work with your local to create one. Local associations should ask administration to manage the time of day to do activities, including school-based sports, to reduce how much heat a person is exposed to. Instead of canceling activities such as practices or competitions because it is too hot outside, administration may consider changing the time of day to either early morning or late afternoon when it may be cooler.  

Monitor classroom temperature by recording the date, time and temperature in a log to keep a record of how hot the classroom is and at what times. This can be used as evidence to show the school district and government officials how hot the classrooms are becoming and demand HVAC system maintenance or the expansion of properly installed HVAC systems in all district facilities.

Dr. Derek Shendell is a professor at the Rutgers School of Public Health where Yvette Way is working toward her master’s degree in public health, majoring in environmental health sciences. They worked in coordination with the New Jersey Work Environment Council to produce this article. 

Heat legislation under consideration in NJ 

The biggest step that can be taken to reduce heat-related illness at K-12 schools is supporting A-1164/S-1358, which would require each board of education to adopt policy establishing temperature control standards and guidelines for school district facilities. 

References and resources

The resources below were used to develop this article and provide more information for those who wish to dig deeper into the issue of heat in schools and other workplaces. 

American Society of Civil Engineers   
Report Card for America’s Infrastructure,” 2021 

Athletic Trainers Society of New Jersey  
Staying Safe in the Heat” 

National Institute of Occupational Safety and Health  
Heat Stress,” 2022 

Occupational Safety and Health Administration  
Heat Stress Guide” 

University of California, Los Angeles  
Impacts of Warming Temperatures on Education and Learning,” 
by R. Jisung Park 
Oct. 8, 2020 

NJEA Review 
“Tackle harmful heat with ventilation and AC,” by Dorothy Wigmore 
September 2021 

U.S. Government Accountability Office 
K-12 Education: School Districts Frequently Identified Multiple Building Systems Needing Updates  or Replacement” 
June 4, 2020