Emergency Preparedness and Response: Extreme Heat

Adverse Health Effects and Susceptible Populations

The two main health issues that can arise as a direct result of exposure to extreme heat are heat exhaustion and heat stroke. Extreme heat can also cause health risks for those with chronic health conditions. Resources included in this section cover how to identify, prevent, and treat these health hazards.

Watch for symptoms of different heat-related illnesses.

National Weather Service Infographic: Heat Illnesses
Knowing the difference between heat illnesses can be a matter of life or death. This National Weather Service infographic explains some of the common differences in symptoms between heat exhaustion and heat stroke. While both are heat-induced, heat stroke is potentially deadly. [url; NWS]

Warning Signs and Symptoms of Heat-Related Illness
This infographic, published by the Centers for Disease Control and Prevention, provides more information about various heat-related illnesses and what to do in each case. [url/pdf; CDC, 2017]

[Esp] Signos y síntomas de advertencia de enfermedades relacionadas con el calor
Esta infografía, publicada por los Centros para el Control y la Prevención de Enfermedades, proporciona más información sobre varias enfermedades relacionadas con el calor y qué hacer en cada caso. [url/pdf; CDC, 2017]

First Aid

Long-term exposure to extreme heat can cause various heat-related illnesses that have different levels of severity. It’s important to identify signs of these heat illnesses and act quickly. In addition the the generl resources shown below, this section includes additional resources for each of the following population groups:

  • Older adults
  • Young children
  • Outdoor workers
  • People with chronic health conditions
  • People experiencing homelessness

First Aid for Heat Illness
Extreme heat affects people differently depending on their age, occupation, health, and location. The CDC (https://www.cdc.gov/disasters/extremeheat/specificgroups.html) (Español) (https://www.cdc.gov/es/disasters/extremeheat/specificgroups.html) offers general information and resources for groups that are more vulnerable to the effects of extreme heat. [pdf; CDC/NIOSH, 2017]

[Esp] Signos y síntomas de advertencia de enfermedades relacionadas con el calor 
[pdf; CDC/NIOSH]

Older Adults

According to the National Institutes of Health, people over 50 years of age are more likely to die from heat-related illnesses. Specifically, those who have heart or blood vessel issues; poorly working sweat glands caused by normal aging; heart, lung, or kidney disease; and are over- or underweight are at risk. Individuals who are currently taking medications that act as diuretics, sedatives, tranquilizers, treat heart or high blood pressure problems, or are taking several prescription drugs at once may also be less able to keep cool.

Heat and Older Adults
The CDC provides general information on elderly individuals’ heat susceptibility and lists ways to prevent heat illness in this population. [url; CDC, 2017]

Hot Weather Safety for Older Adults
This page from the NIH’s National Institute on Aging website features detailed information about signs of heat illness and how elderly individuals can lower their risk. The page also provides resources for seniors to get help or learn more about heat illnesses.[url; NIH, 2016]

[Esp] El calor y los adultos mayores
El CDC brinda información general sobre la susceptibilidad al calor de las personas mayores y enumera formas de prevenir las enfermedades causadas por el calor en esta población. [url; CDC, 2017]

[Esp] Hipertermia
Esta página del sitio web del Instituto Nacional sobre el Envejecimiento de los NIH presenta información detallada sobre los signos de enfermedades causadas por el calor y cómo las personas mayores pueden reducir su riesgo. La página también proporciona recursos para que las personas mayores obtengan ayuda o aprendan más sobre las enfermedades causadas por el calor. [url; NIH, 2010]

Young Children

The American Academy of Pediatrics (AAP) suggests that children be allowed to play outside unless the heat index is reported to be 90º F or higher; at this point, extreme heat can be detrimental to a child’s physical health. It’s important to note also that, when conditions are too hot to allow children to play outside, keeping your home cool is even more important. For more information on how to do that, you can see our Prepare and Act and Policy Levers and Actions pages.

The American Academy of Pediatrics also reports that heat stroke resulting from having been left in a parked car is a leading cause of death in children under 15. Children’s bodies heat up three to five times faster than adults, and temperatures inside parked cars can increase 20º F every 10 minutes. As a result, heat stroke can occur even when outside temperatures are only 57º F.

Heat and Infants and Children 
This CDC web page recommends ways to keep kids cool, hydrated, and safe in extreme heat. [url; CDC, 2019]

Protecting Children from Extreme Heat: Information for Parents
This article by health expert Dr. Dele Davies explains how to keep children safe and cool during extreme heat events and when to contact a healthcare professional about symptoms of heat illness. [url; Healthy Children, 2021]

Prevent Child Deaths in Hot Cars
This resource on the American Academy of Pediatrics’ Healthy Children site includes reminders for parents or child care providers to ensure children’s safety during extreme heat. It also outlines actions to take when a child is found alone in a parked car. [url; AAP/Healthy Children, 2020]

[Esp] Los bebés, los niños y el calor 
Esta página web de los CDC recomienda maneras de mantener a los niños frescos, hidratados y seguros en condiciones de calor extremo. [url; CDC, 2017]

[Esp] Calor extremo: mantener a los niños seguros cuando las temperaturas se disparan
Este artículo del experto en salud, el Dr. Dele Davies, explica cómo mantener a los niños seguros y frescos durante los eventos de calor extremo y cuándo contactar a un profesional de la salud acerca de los síntomas de una enfermedad causada por el calor. [url; Healthy Children, 2021]

[Esp] Prevenga las muertes de niños en vehículos calientes 
Este recurso en el sitio Healthy Children de la Academia Estadounidense de Pediatría incluye recordatorios para padres o proveedores de cuidado infantil para garantizar la seguridad de los niños durante el calor extremo. También describe las acciones a tomar cuando un niño se encuentra solo en un automóvil estacionado. [url; AAP/Healthy Children, 2020]

People with Chronic Health Conditions

This group includes people living with diabetes, heart disease, asthma, Alzheimer’s Disease, or mental illness, among other conditions.

Heat and People with Chronic Medical Conditions
The Centers for Disease Control and Prevention provide information for individuals with chronic medical conditions to stay safe during extreme heat. [url; CDC, 2017]

Climate Change and the Health of People with Existing Medical Conditions
Changes in exposure to extreme heat, extreme weather events, and poor air quality can increase the risk of illness in people with existing medical conditions. This factsheet from EPA includes information on how various chronic illnesses can increase sensitivity to heat. It also links to other CDC and EPA resources. [pdf; EPA, 2016]

[Esp] Las personas con afecciones crónicas y el calor 
Los Centros para el Control y la Prevención de Enfermedades brindan información para que las personas con afecciones médicas crónicas se mantengan seguras durante el calor extremo. [url; CDC, 2017]

Outdoor Workers

To work safely in heat, workers should stay hydrated, rest often, and utilize shade. For information about housing needs and resources for this community, visit our Policy Levers and Actions page.

Heat and Outdoor Workers
This CDC web page provides general information for outdoor workers to reduce health risks from heat exposure. [url; CDC, 2021]

OSHA’s Heat Illness Prevention Campaign
The Occupational Safety and Health Administration’s campaign details the dangers of working in extreme heat and lists the responsibility of employers in keeping workers safe. [url; OSHA, 2022]

OSHA-NIOSH Heat Safety Tool App
This downloadable app from the CDC’s National Institute for Occupational Safety and Health provides real-time heat index updates by location and can be used by workers and employers to plan outdoor work activities safely. [url; NIOSH, 2021]

[Esp] Las personas que trabajan al aire libre y el calor  
Esta página web de los CDC brinda información general para que los trabajadores al aire libre reduzcan los riesgos para la salud debido a la exposición al calor. [url; CDC, 2021]

People Experiencing Homelessness

Those who are unable to access shelters or air conditioning are especially at risk when it comes to extreme heat.

How to Help Homeless People in a Heat Wave
National nonprofit Invisible People recommends giving out water, sun protection, baby wipes, handheld battery-operated fans, and/or money. It’s also helpful to connect people experiencing homelessness with cooling centers and be attentive to those who are experiencing symptoms of heat illness. [url; Invisible People]


Latest page update: May 11, 2022.