With global temperatures on the rise, it’s important to understand what heat stress is and how to protect yourself and your co-workers from its effects.

Heat stress is the combination of environmental heat, physical activity, and clothing worn, which can cause an individual to become overheated and experience symptoms of heat illness.

Heat illness can range from heat cramps and heat exhaustion to the most serious, heat stroke. Heat-related illnesses occur when a person’s body is unable to cool itself properly and can lead to serious health problems and even death. The most common signs and symptoms of heat stress are excessive thirst, headache, dizziness, nausea, and fatigue.

Employers need to understand the risks of working in hot environments and take steps to reduce the risk of heat stress from occurring.

Employers can provide their workforce appropriate cooling materials like vests and apparel, such as cooling hats, cooling towels, and moisture-wicking clothing. It’s important that workers have access to cool, clean drinking water that is cooler than ambient air as well as electrolytes to help them stay hydrated. Developing a hydration program to guide employees on best use practices and how to incorporate hydration into their breaks and shift lengths will provide an immediate impact and help avoid over-exertion. Ideally break locations are indoors or under a shaded area.

Ergodyne specializes in cooling technologies that are engineered to ensure workers stay cool. Wet evaporative materials combine water and airflow to draw heat away from the body – delivering instant cooling while keeping you cooler longer. Evaporative materials like PVA, microfiber, acrylic polymers and embedded polymers offer workers a variety of cooling solutions including towels, vests, headbands, sleeves, and caps. By providing your employees with products designed to provide instant cooling relief, you will and help them regulate body temperature, allowing them to stay comfortable and productive in hot working conditions.

Ergodyne Cooling Technology

Ergodyne’s Microfiber Cooling Technology

Those who spend long hours in a hot environment, whether outdoors or indoors, are more susceptible to dehydration, exhaustion, heatstroke, and other heat-related health issues.

Another easy way to help prevent heat stress injuries is through the implementation of a hydration plan and regular use of electrolyte – replenishing beverages. Primarily focusing on water and sodium electrolyte replenishment (the primary electrolyte lost in sweat), these powdered drink mixes, ready-to-drink beverages, and popsicles help replace lost electrolytes that are essential for mental clarity, workplace performance, and sustained productivity. Sword Performance’s line of rehydration products impact workplace safety immediately delivering industry-leading rehydration and ease-of-use strategies to fit the needs of all employees. From environments in the extreme heat & humidity to a moderate temperature-controlled, use of SWORD and SHIELD hydration products are a proven way to reduce heat stress in the workplace. Sword Performance beverages are referred to as DRINKABLE PPE, with how much a role they are playing in the daily safety routine in the fight against heat stress injury.

As not all work environments are created equal, keeping your employees properly hydrated is more of a science than you would think. Understanding all aspects of the work environment – from ambient temperature to the PPE being worn – plays a factor in determining what type of hydration and how frequent electrolyte replenishment is needed.

Heat stress is a real danger in the workplace, and it is important to understand the risks and take steps to reduce the risk of heat-related illnesses. By providing workers with cooling apparel and sports drinks, employers can help keep their workers safe and healthy in hot working conditions.

The human body responds to the heat by increasing sweat production to try and keep itself cool, but when the temperature is too high for the body to manage it can cause severe medical issues.

Heat Stress Stage 1


The body’s means of controlling its internal temperature starts to fail.

Heat Stress Stage 2


Once body temps reach 99.7ºF (37.6ºC), heat stress has begun to affect the body.

Heat Stress Stage 3


Severe illness occurs when body temperature reaches 104ºF (40ºC).

Types of heat stress can range from mild cases such as heat exhaustion, to more serious cases like heat stroke and sun poisoning.

Symptoms of heat stress may include fatigue, cramping, nausea, headaches, fainting, confusion, and dizziness.

Heat Rash

Heat Rash

Heat rash is an irritation of the skin that usually appears when sweat ducts become clogged and sweat can’t get to the surface of the skin. It can be uncomfortable, causing itching and prickly sensations on the skin.

Heat Cramps

Heat Cramps

Heat cramps, usually in the muscles of the stomach, arms, or legs, are another common ailment.

Heat Exhaustion

Heat Exhaustion

Heat exhaustion is caused by dehydration, loss of body salts and an excessive loss of fluids due to sweating. Its symptoms can range from feeling tired and weak to nausea and vomiting.

Heat Stroke

Heat Stroke

Heat stroke is a more significant issue and is characterized by an extremely high body temperature, confusion, and disorientation. Without prompt medical attention, heat stroke can be deadly.

Sun Poisoning

Sun Poisoning

Sun poisoning is a severe form of heat stroke and can cause severe blistering and itching, accompanied by other signs of heat exhaustion.

If left untreated, all these types of heat stress can cause permanent damage and in extreme cases, death. It is important to stay hydrated, take frequent breaks from direct sun exposure, and stay out of areas with high humidity when outside in extreme heat.

Contributing factors to heat stress

Personal contributing factors to heat stress can include the individual’s clothing choices, level of physical activity, general physical condition, and use of medication. People with chronic medical conditions, or those who take medications, may be at a higher risk for heat-related illnesses.

Environmental factors can also play a role in heat stress. Sun exposure, air temperature, humidity levels, and shade availability must be considered. In hot, humid conditions, perspiration is unable to evaporate quickly, making the individual more susceptible to heat exhaustion and other heat-related illnesses. Wearing protective gear like sunglasses, wide-brimmed hats, and sunblock is essential to prevent sun-related health risks.

Tangible and Intangible Costs of Heat Stress

Heat stress is an increasingly prominent issue as the planet’s average temperature rises due to human-driven climate change. It is a problem with both tangible and intangible costs.

The most tangible cost of heat stress is its effects on physical health. Those who spend long hours in a hot environment, whether outdoors or indoors, are more susceptible to dehydration, exhaustion, heatstroke, and other heat-related health issues.

Intangible costs include economic impacts such as a decline in labor productivity, job turnover, and decreased business efficiency. Other intangible costs of heat stress can be measured in quality of life and comfort levels, especially for people living in densely populated, urban areas. These costs are often taken for granted but can have far-reaching consequences. For instance, reduced educational performance can limit future economic opportunities and reduce quality of life in affected areas. It’s therefore essential to mitigate the causes of heat stress and take proactive steps to reduce its associated costs.

Heat Stress is Costly

In the United States, heat stress is costing businesses an estimated $93 billion per year due to an increased risk of workplace accidents and lower employee productivity. Furthermore, higher temperatures increase the risk of cardiovascular and other health complications. To make matters worse, there is a projected 11 percent increase in the annual costs of heat stress between 2021 and 2050, as the climate continues to warm. As businesses grapple with rising expenses, they must be mindful of implementing protective strategies to ensure the health and safety of their employees.

  • Average cost for a medically consulted injury $31,000

  • Average cost for a fatal accident $1 million/fatality

  • In 2020 – over 1,940 injuries cost employers over $60 million

Physiology of Sweat

The human body contains many functions and features, and one of the most amazing is sweating. Sweat, which is composed of primarily water and sodium electrolytes, is the body’s natural cooling system that helps regulate its internal temperature. Sodium is the master regulator of fluid distribution in the body and is the primary way the body moves water from one compartment to another. More than 85% of the electrolyte content found in sweat is sodium in the form of salts, which is why when we taste our sweat, it is salty. The sweat glands are responsible for releasing this fluid which, upon evaporating, takes heat away from the body. Sweating can occur all over the body, but is especially common on the palms, forehead, neck, and feet. The amount of sweat released from an individual will depend on several factors, such as the climate, stress levels, physical exertion, and any medical conditions the individual might have. No matter the cause, sweating helps us to stay healthy and active in all kinds of situations.

When it is hot outside and you start feeling the effects of heat stress, it is important to take steps to protect yourself. First, stay hydrated and drink plenty of fluids including water and replenish your electrolytes. Second, seek shelter in air-conditioned spaces when available. If you are unable to do this, limit your outdoor activities and find ways to stay cool such as taking a cold shower or applying wet towels or clothes to your skin. Third, dress for the weather in lightweight and light-colored clothing and protect yourself from the sun with a wide-brimmed hat and sunscreen. Finally, do not forget to check in on those with chronic medical conditions who may be at an increased risk of heat-related illness.

By conducting a heat hazard assessment specific to your organization, you can implement a tailored approach and develop a heat stress program that includes training combined with appropriate PPE, electrolyte replenishment beverages and planning for optimal working hours/conditions, you can achieve a reduction in heat stress related illnesses.

Bottom line: Heat stress is 100% preventable!

The key is to stay cool and hydrated during periods of hot weather. By drinking plenty of water, wearing light-colored, loose-fitting clothing, avoiding strenuous physical activities, and seeking cool, air-conditioned locations whenever possible, heat stress can be completely avoided. Taking frequent breaks in shaded areas, monitoring the heat index, and avoiding outdoor activities during the hottest parts of the day are all key preventive measures to protect yourself against heat-related illness. With the right precautions in place, heat stress is avoidable.