Heat stress happens when your body starts having problems regulating internal temperature due to high external temperatures. It may lead to heat-related illnesses like heat exhaustion and heatstroke.
Heat stress can become a health crisis. Knowing the signs of heat stress and how to prevent it can help keep you and others safe when temperatures are high.
Many people may experience heat-related illnesses during the summer months due to rising temperatures. Heat stress can also occur as a result of particular environmental conditions, such as a workplace that exposes you to higher-than-usual temperatures.
People who may be particularly vulnerable to the effects of high heat include older adult adults and children. People who work outdoors or are athletes are also at a higher risk.
Read on to learn how to spot the signs of heat stress, what to do if you or others are experiencing heat stress, and how to prevent heat stress.
Heat stress happens when your body begins to lose the ability to control its internal temperature in response to heat. It’s not the same as simply feeling hot for a moment. It’s the first sign that your body is struggling to regulate its temperature properly.
Symptoms of early heat stress can include:
- fatigue
- thirst
- mild discomfort
Early heat stress is less severe than heat exhaustion or heatstroke, but the
Heat-related illnesses
- heatstroke
- heat exhaustion
- rhabdomyolysis
- heat syncope
- heat cramps
- heat rash
Heatstroke is the most severe type of heat-related illness and can cause death if treatment is delayed.
Knowing the signs of heat stress can help you notice when you or someone around you is experiencing heat stress and take prompt action to prevent it from worsening and developing into a more severe condition.
The symptoms of heat stress may vary depending on how severe it has become and whether it has developed into a heat-related illness.
Symptoms can include:
- muscle cramping
- fast heart rate or breathing rate
- confusion
- headache
- feeling irritable
- extreme thirst — this is a late symptom of heat stress
- pale skin
- excessive sweating or inability to sweat
- fainting
- vomiting
If you experience more severe symptoms such as vomiting, confusion, or inability to sweat despite feeling hot, these are signs that heat stress has progressed, and it’s time to get immediate medical help.
Heat stress happens when your body becomes too hot and cannot regulate its internal temperature.
According to the
- Health conditions: These may include diarrhea, vomiting, diabetes, heart disease, obesity, or a lack of physical fitness.
- Overexertion: Doing too much in the heat can put you at risk of heat stress. For example, not taking breaks, working, or exercising a lot.
- Medications: Some medications can affect the body’s ability to regulate temperature. These include blood pressure medications, depression medications, and diuretics.
- Environment: High temperatures, high humidity, and hot equipment are a few examples. A lack of breeze can also increase the risk.
- Poor acclimatization: For example, workers who are new or returning from time away may not have time for their bodies to adjust to the hot environments.
Other factors can also include:
- having suffered from heat illness in the past
- being dehydrated
- being over age 60
- wearing PPE or non-breathable clothing
- having consumed alcohol in the past 24 hours
High humidity can also contribute to heat stress. You may also be more likely to feel the effects of the heat if you exercise in hot weather or spend time in a place that can heat up, such as a car.
If you notice signs of heat stress, it’s important to stop what you’re doing and take a break. Make sure to rehydrate by drinking water or other fluids. Find a cool place and take off extra layers so your body can get back to its normal temperature.
Heat stress can lead to heat-related illnesses such as heat exhaustion and, more severely, heatstroke.
If someone you know is experiencing any signs of heat exhaustion, the NHS recommends the following steps:
- Move them to a cool place.
- Remove excess clothing, such as jackets and socks.
- Get them to drink water or a rehydration drink.
- Cool their skin with cool water or a fan. Cold packs wrapped in cloth under the armpits or on the neck can also help.
It’s important to stay with the person until they feel better. This should be within around 30 minutes. If they don’t improve within this time, it’s important to get immediate medical help. They may have heatstroke.
Don’t wait to get help if a person is unresponsive or responding incoherently. Call for medical assistance immediately.
Heat stress can lead to heat-related illnesses. It’s important to know the signs of each one and what to do if you or someone around you is showing signs.
According to the
| Symptoms | First aid | |
|---|---|---|
| Heatstroke | – confusion, slurred speech – loss of consciousness – hot, dry skin or excessive sweating – seizures – very high body temperature | – Call 911 for emergency medical care as heatstroke can be fatal or cause disability. – Move the person to a cool area. – Use cold water or wet cloths to cool the person. – Circulate air around the individual. – Place cold wet cloths or ice on the head, neck, armpits, and groin. |
| Heat exhaustion | – headache – nausea – dizziness – weakness – irritability – thirst – heavy sweating – elevated body temperature – reduced urination | – Get urgent medical evaluation or call 911. – Move the person to a cool place. – Give them liquids to drink. – Remove unnecessary clothing. – Cool the person with cold compresses or cold water on head, face, and neck. – Encourage sips of cool water. |
| Rhabdomyolysis | – muscle cramps/pain – dark urine – weakness – exercise intolerance – can have no symptoms | – Stop activity. – Drink more water. – Seek immediate medical care. – Ask for a rhabdomyolysis check. |
| Heat syncope | – muscle cramps – pain or spasms in the abdomen, arms, or legs | – Sit or lie down in a cool place. – Slowly drink water or a sports drink. |
| Heat cramps | – Get urgent medical evaluation or call 911. – Move the person to a cool place. – Give them liquids to drink. – Remove unnecessary clothing. – Cool the person with cold compresses or cold water on the head, face, and neck. – Encourage sips of cool water. | – Drink water and have a snack or a sports drink every 15 to 20 minutes. – Seek medical help if cramps last longer than 1 hour or if the person has heart problems or is on a low salt diet. |
| Heat rash | – red clusters of pimples or small blisters (often in the neck, chest, groin, under breasts, and elbow creases) | – Keep the rash area clean and dry, and avoid humidity in general. – Avoid using creams and ointments, and prefer talc powder instead. – Consult with doctor if rash doesn’t improve within days. |
Heatstroke and heat exhaustion are the most severe forms of heat illness.
Learn more about the difference between these two conditions.
Strategies you can use to help prevent heat stress include:
- staying indoors and avoiding strenuous activities during the hottest part of the day
- keeping in shaded areas
- spending 2 or 3 hours of the day in a cool area
- taking cool showers or baths
- drinking water regularly
Employers can help keep their workers safe by maintaining heat safety protocols and providing access to cooler areas. Some workplaces, such as bakeries and foundries, have an increased risk due to the hot environments.
Thick work clothing, such as PPE, that retains the heat can also increase the risk of heat stress.
If you spot the signs of heat stress early, you’re more likely to recover fully and prevent it from becoming more serious.
However, more serious conditions such as heatstroke are a medical emergency.
The recovery period after experiencing heat stress is important to ensure optimal healing and well-being and to help prevent complications.
Someone who has experienced heat stress may also feel more emotional, so it’s important to take the proper time and care to recover.
It’s important to be aware of the signs of heat stress in hot weather or hot environments. Heat stress can lead to more severe conditions, such as heat exhaustion and heatstroke, which is life threatening.
Prevention includes staying in shaded areas and making sure to spend a few hours of the day in a cool area. You should also drink water regularly.
Certain people may be more at risk, so it’s important to take extra care if you belong to one of these groups.