Heat Illness: What It is and How to Avoid It

Summer and warm weather usually means vacations, barbecues, and time at the beach. But when it comes to work, too much heat, with too little protection, can be dangerous. This is especially true for those who work outdoors.  

There are many different risks, including heat illness, that come with increased heat and humidity. While some jobs carry more risk than others, all outdoor workers face some danger from hot and humid weather. Heat illness can also impact those who spend hours outdoors for gardening, athletics, or other outside activities. 

Who is at Risk? 

Those who work primarily or exclusively outdoors. Agricultural workers, landscapers, utility workers, and those in the construction industry are at increased risk for heat-related illnesses. Even event staff, delivery drivers, and workers or others who are outside for shorter periods of time face risks from the heat – especially because they may not be as aware of the risks or take precautions. As the CDC notes, even short-term exposure to hot and humid weather can have an impact.  

At the same time, the risks (and preventative measures) depend on your environment, both from a geographic and workplace standpoint. For example, while a roofing team in an urban setting may not need insect repellent, they should bring plenty of water. Due to the urban heat-island effect and the reflection of heat from roadways and concrete surfaces, temperatures in these types of workplaces can be much higher, and can exacerbate air pollution, which is

generally worse in urban settings. This can inflame existing conditions and cause long-term respiratory issues over time.  

A work crew in San Antonio has a different degree of risk for heat-related illness than a team in Seattle. But that doesn’t mean those in Seattle are not at risk for heat illness, especially if they spend many hours in the sun or particularly hot weather.  

Additionally, those with preexisting conditions or other diseases face increased risks of heat illness. Those over 65 and individuals with obesity, heart disease, or high blood pressure are more susceptible to heat-related illness. Inexperience should also be a consideration; workers, tourists, athletes, or others who are new to a job or activity, or not acclimated to a particular  environment, are more prone to heat illness.  

What are the Signs? 

Dehydration and sunburn are well-known risk, but heat-related illnesses such as heat exhaustion and heat stroke are the primary danger of working outdoors during the summer. Each year, thousands of Americans are hospitalized for heat-related illness, and there are more than a thousand heat-related deaths annually. While the impact from summer weather can often be mild — dehydration, muscle cramps, and excessive sweating — the more serious conditions can be deadly.  

Types of Heat-Related Illness 

As the Occupational Health and Safety Administration explains, outdoor workers face many different types of heat-related illness. For the most part, heat illnesses fit onto a scale of severity. At the less significant end are dehydration and heat cramps. While these may cause discomfort, alone they are not life-threatening. They can, however, increase the risk of workplace accidents.  

On the more serious side is heat exhaustion, and ultimately, heat stroke. These should not be taken lightly: on average, more than 1,300 Americans die from heat stroke every year. 

Heat Stroke: The most serious heat-related illness, heat stroke is caused when the body’s ability to regulate temperature is overwhelmed and unable to cool down. This causes the temperature to rapidly rise. If left untreated, heat stroke can result in death. Dial 911 immediately if you see symptoms of heat stroke. 

• Symptoms – High body temperature (104 degrees F and up) is the key symptom. In addition, there may be a rapid pulse and breathing, hot and dry skin, and dizziness or confusion. In some cases, a loss of consciousness can occur.  

• Treatment – Heat stroke should be treated by medical professionals. But there are a few important steps you can take to lower the body temperature until help arrives. Move impacted individuals indoors or to a shaded area, and cool the Treatment – Heat stroke should be treated by medical professionals. But there are a few important steps you can take to lower the body temperature until help arrives. Move impacted individuals indoors or to a shaded area, and cool the body with wet towels or water. Do not use ice packs or ice water, as this can have an adverse effect.  

Heat Exhaustion: Less severe but still serious, heat exhaustion occurs when the temperature regulation system is strained but not overwhelmed. If untreated, it can escalate to heat stroke.  

• Symptoms – The symptoms for heat exhaustion are similar to heat stroke: heavy sweating, dizziness and fainting, headaches and nausea. Any of these symptoms should immediately warrant concern, and immediate steps should be taken to cool down.  

• Treatment – The primary treatments include hydration and lowering the body temperature. Move to a cool environment, and remove excess clothing. Lie down with legs elevated to improve blood flow, and hydrate with cold water or sports drinks. Individuals experiencing heat exhaustion symptoms should rest for at least 24 hours.  

Related Illnesses: While heat stroke and heat exhaustion are the greatest concerns, there are other types of heat-related illnesses that are less severe but still serious.  

• Heat Syncope – Otherwise known as heat collapse or fainting, heat syncope is a loss of consciousness. To cool the body in hot temperatures, the blood vessels in the skin dilate, which leads to a temporary decrease in blood flow to the brain. Quick movement can trigger an episode. Those who stand for long periods outside, or those who have sudden changes in body position while outdoors, are more susceptible.  

• Heat Cramps — A manifestation of dehydration, heat cramps are a type of muscle cramp. Instead of occurring because of exertion, they’re caused by an electrolyte imbalance. The large muscle groups like the calves, thighs, and abdomen, are particularly susceptible to cramps.  

Other Dangers 

Excessive Sweating: Sweating helps the body regulate temperature, but it also makes many jobs or tasks more challenging. Sweaty hands reduce grip strength and dexterity, making it more difficult to handle tools. Sweaty skin can also lead to slips, trips, and falls. In addition, sweat can be a conductor of electricity. Those working around electrical currents or with power tools could be at risk of electric shock. Fogging Glasses: Many outdoor jobs require the use of safety goggles, which can fog up due to the temperature difference between the goggles and the skin. The greater the heat and humidity, the more likely this is to occur. Fogging can happen in a matter of seconds and create a dangerous situation. Applying anti-fogging agents to lenses minimizes this risk. 

Reduced Cognitive Function: For a variety of reasons, summer’s heat and humidity can impact cognitive function. Outdoor workers can experience reduced cognitive function due to blood flow being routed to the skin’s surface, rather than to the brain. Dehydration, discomfort, and fatigue can also impair decision-making and other cognitive processes.  

Skin Damage: It’s common knowledge that sun exposure can lead to sunburn. In the short-term, sunburn can cause pain, discomfort, blistering and even infections. While sunburn isn’t always taken seriously, it can have deadly long-term impacts. According to the Skin Cancer Foundation, even a few instances of sunburn can double your risk of developing skin cancer.  

Staying Safe in the Sun: The dangers and challenges associated with working outdoors during the summer are numerous. But there are a number of preventative measures workers can take. While these vary between workplaces, they all have the same goals: to limit sun exposure and maintain healthy body temperature and hydration. Below are some of the steps all outdoor workers should consider: 

• Clothing – Wear clothing that combines sun protection and breathability. While the general public may be wearing shorts and sandals, that’s not a viable option for many outdoor workers. Lightweight, breathable fabrics minimize water loss and maintain proper body temperature. Clothing with SPF can help with sun protection, as well.  

• Hydration – Most of us could benefit from drinking more water to stay hydrated. But when it comes to outdoor work, proper hydration is critical in preventing heat-related illness. There’s no “one-size fits all” approach when it comes to how much water one should drink when working, playing or engaging in other outdoor activities. Simply put, the best way to stay hydrated is to always have water on hand. Sports drinks or waters that include electrolytes can be beneficial, as well. 

• Frequent Breaks – The risks for heat-related illnesses and accidents multiply the longer people are exposed to sunny, hot, or humid conditions. To lower the risk of heat-related illness, workers and those spending time outside should take frequent breaks, ideally in the shade or in air conditioning. One common standard is to take a break of at least ten minutes every two hours.  

• Cooling Measures – Nearly every kind of heat-related issue stems from high body temperature. While on the worksite or spending time outdoors, it’s important to take extra steps to keep the body temperature stable. Use wet towels, cooling vests, portable fans or cooling neck wraps to bring one’s temperature down, as long as it’s safe to do so.  

Ultimately, the best way to stay safe when working or spending time in the heat is to be prepared, understand the risks unique to your environment — and if working or participating in

outdoor activities in a group — be aware of your peers and any potential heat-illness warning signs. 

NSC’s training video teaches ways to encourage employees to prevent heat-related illness, and how to recorgnize the signs of heat exhaustion. NSC offers additional heat stress-related safety products here.