Recognizing the Signs & Symptoms of Heat Exhaustion

Millions of U.S. workers are exposed to high temperatures and hot work environments on a regular basis. And every year, thousands of workers become sick from occupational heat exposure. 

Heat cramps, heat exhaustion, and heat stroke are all examples of heat-related illnesses that workers may encounter. 

Heat stroke is the most dangerous, as it can often turn fatal. However, heat exhaustion is the one most commonly reported for occupational heat illnesses. 

For this reason, heat exhaustion will be the primary focus for this article, although other forms of heat stress will also be discussed. 

Training Workers on Heat Stress

Under federal law from the Occupational Safety and Health Act, employers are responsible for providing a workplace free of any known hazards. This includes occupational heat exposure. Steps must be taken to reduce an employee’s risk of experiencing a heat-related illness. 

Training is an essential aspect of any health and safety program. 

Workers should be trained to understand the differences between various forms of heat stress, be able to recognize the signs and symptoms of each, and have a basic understanding of treatment and first aid options.

Symptoms of Heat Exhaustion

Early recognition of the signs and symptoms of heat exhaustion can help reduce the severity of this type of illness. If the condition is prolonged, it could lead to a heat stroke which is potentially life threatening. 

Symptoms of heat exhaustion include: 

• Cool, moist skin
• Heavy sweating
• A weak, rapid pulse
• Muscle cramps
• Nausea
• Fatigue
• Thirst
• Headache
• Dizziness
• Irritability
• Low blood pressure upon standing

These signs and symptoms can either develop slowly or they could have a rapid onset. 

With heat exhaustion at work, employees may not realize they are experiencing a heat-related illness. After all, many of these symptoms (such as sweating, fatigue, and thirst) are normal reactions from working hard and in high temperatures. 

But when multiple symptoms are present and the condition worsens, it could result in serious health issues. Workers should seek first aid immediately. 

Heat Exhaustion Treatment

If the symptoms of heat exhaustion are not caught early enough, treatment may be necessary. OSHA requires first aid equipment be readily available at all times. There should also be workers present during each shift who are trained in basic first aid. 

OSHA recommends the following steps for treating heat exhaustion:

• Take the worker to a cool area (somewhere with shade or air conditioning)
• Cool the worker with active cooling techniques such as:
  • Providing cold packs on the head, neck, armpits, and groin
  • Placing a cold, wet towel on the worker’s head and neck
  • Immersing the worker in cold water or an ice bath
  • Remove outer layers of clothing
  • Use fans for additional cooling, when possible
• Never leave a worker alone if they are experiencing a heat-related illness
• When in doubt, call 911!

Additional steps you can take, recommended by the Mayo Clinic, include:

• Lay the person down and elevate the legs and feet
• Provide cool drinking water or other nonalcoholic beverages without caffeine
• Contact a doctor if symptoms worsen or if they don’t improve within one hour.
• Call 911 if the person faints, has a seizure, or their body temperature exceeds 104 F. 

Preventing Heat Exhaustion

Recognizing the symptoms of heat exhaustion and understanding proper first aid treatment is important. But even more so, is a solid understanding on how to prevent it from occurring in the first place.

Both management and workers need to commit to safe work practices that can help prevent heat exhaustion at work. 

Water, rest, and shade are key factors for preventing heat exhaustion. 

Employers should provide cool drinking water for all workers, especially those working outdoors or in high temperatures. It’s important for workers to stay hydrated at all times, and remember to drink plenty of water throughout the day. Not just when they are thirsty. 

Workers should also be encouraged to take frequent breaks throughout the day. When temperatures are high or when there is an elevated risk for heat exhaustion, the length and frequency of breaks may need to increase. 

Workers need to have access to a cool area where they can take their breaks. This could simply be a shady area, an air-conditioned vehicle, or a nearby tent or building. A place with fans and misting devices is ideal for places with extreme temperatures during summer months. 

Additionally, employers can establish administrative controls to prevent heat exhaustion. Examples of such efforts include:

• Modifying work schedules and activities for workers who are new to warm environments.
• Consider scheduling labor-intensive work at a cooler time of day, such as early morning or late afternoon.
• Rotate job functions among workers to help minimize exertion and heat exposure.
• Implement a buddy system for anyone exposed to heat stress environments.

Other Types of Heat Stress

Remember, there are multiple types of heat-related illnesses. It’s often difficult to diagnose which one is occurring, since the signs and symptoms for each can occur simultaneously. 

To help you get a better understanding of the differences, here are the definitions of heat rash, heat cramps, and heat stroke – as defined by the Mayo Clinic. In addition to heat exhaustion, these are the most common types of heat stress that workers experience. 

Heat Rash

Develops when sweat glands or blocked pores trap a person’s perspiration under their skin. Appearance can vary from superficial blisters to deep, red bumps. May feel “prickly” or itchy. 

Heat Cramps

Painful, uncontrollable muscle spasms that usually occur in the legs, arms, or back. Spasms can be intense and may be prolonged until the person is able to rest and rehydrate. 

Heat Stroke

Occurs when the body temperature rises to 104 F or higher. Caused by prolonged exposure or physical overexertion in high temperatures. Can quickly damage the brain, heart, kidneys, and muscles if immediate care is not received. 

In relation to these heat-related illnesses, heat exhaustion is more serious than heat rash and heat cramps, but not as severe as a heat stroke. 

For more information on the different types of heat stress, including a full list of symptoms and treatment options, check out this related post on preventing heat stress in the workplace. 

Avoiding Heat Stress in the Workplace

Anyone working outdoors or in high temperatures has the potential for suffering from heat stress. This includes indoor workers as well. Those who operate near radiant heat sources, in humid areas, or those who make direct physical contact with hot objects face the same risk.

Whether it’s inside a factory or outdoors… if the conditions are right, heat exhaustion and other heat-related illnesses could occur.

Employers must train and protect their workers from the hazards of heat stress. 

To comply with the occupational safety and health regulations, you can either invest the time and resources to research, develop, and deliver a heat illness prevention training program internally… or, you can check out our “all-in-one” Heat Illness Prevention Training Kit.  

Our Heat Illness Prevention Training Kit is a convenient and cost-effective training solution, perfect for in-house safety coordinators. It includes an interactive training program, student’s handbook, instructors handbook, student tests, training logs, certificates, wallet cards and more.