This Is How to Prevent Heat Stroke

Heatstroke is the silent killer. Extreme heat is more deadly than hurricanes, floods, and tornadoes combined. Excessive heat was the leading cause of weather-related deaths in the U.S. In 2023, a record 2,325 people died from heat in the U.S. alone. Summers have warmed in 97% of 242 U.S. cities analyzed by an average of 2.6°F since 1970. As climate change accelerates, the frequency and intensity of hot days and heat waves are rapidly increasing.

Extreme heat contributes to a range of health conditions, including hospitalization, cardiovascular diseases, and death. Deaths due to heat-related illnesses in the U.S. have more than doubled over the last 25 years. The health impacts of heat are particularly adverse among older adults due to their decreased ability to adapt. A single episode of exertional heat stroke can lead to chronic health disorders and accelerated aging.  The hazard of extreme heat is often overlooked because it lacks the visible drama of roofs being ripped from homes or streets being turned into rivers.

If you work outdoors or in hot environments such as steel mills, kitchens, bakeries, or offices without air conditioning, it’s important to recognize when the heat becomes unsafe. Understanding how to prevent heat stroke and heat exhaustion is essential. In this post, we will share key information on staying safe and managing the heat effectively.

Learn How to Stay Safe in the Heat!
HEAT ILLNESS PREVENTION: KEEP IT COOL
Keep yourself safe, reduce your company’s legal liability, and ensure everyone knows the signs and symptoms of heat exhaustion and heat stroke and how to stay cool. It takes less than 30 minutes!

How Your Body Manages Heat and Prevents Heat Stroke

Your body constantly maintains a core temperature of around 37 degrees Celsius (98.6 degrees Fahrenheit). The body gains heat by using the food you eat to produce energy and through radiation from the sun. If your body temperature rises too high, it can lead to heat exhaustion or heat stroke. Sweating is the primary way your body cools itself, but excessive humidity can hinder sweat evaporation, increasing the risk of overheating. Age, fitness level, underlying medical conditions, and individual heat tolerance influence your susceptibility to heat stress.

One of the primary ways the body cools itself is through the evaporation of sweat. When humidity is high, sweat cannot evaporate efficiently, leading to overheating. This is why the humidity level is crucial when discussing heat stress. The perceived temperature can be significantly higher in high humidity than what the thermometer reads.

Warning Signs and Symptoms of Heat Exhaustion Vs Heat Stroke

• Muscle cramps
• Heavy sweating
• Weakness or tiredness
• Dizziness
• Headache
• Confusion
• Fainting

Exposure to heat and toxic chemicals simultaneously is exceptionally challenging for the body. Make sure you know how to work with toxic chemicals at your work by taking the Free WHMIS training or the Free Hazard Communication Standard Training.

Measuring Your Heat Risk

The American Industrial Hygiene Association has an upgraded phone application that uses cutting-edge science to make heat stroke prevention recommendations based on real weather conditions. The app is free.

A simple method to assess your heat risk is monitoring your heart rate. If your heart rate remains consistently above the value obtained by subtracting your age from 180 for several minutes, it indicates an increased risk of heat illness. Investing in a smartwatch that monitors heart rate can be beneficial.

If you work in the heat, get a smartwatch. Watches that measure your heart rate are readily available and inexpensive. Soon, your smartwatch will be able to tell you when you are at risk of heat stroke, but until then, keep it simple.

Take Frequent Breaks and Acclimate to Prevent Heat Stroke

You are most likely to get heat stroke when you are exposed to a sudden increase in temperature, such as during an early-summer heat wave or travel to a hotter climate. Most occupational heat-related deaths occur in the first 1-3 days of working in the heat. Even if you recover from heat stroke, you may have long-term damage to your heart and nervous system.

It’s important to ease into working in a heatwave and allow your body time to acclimate to the conditions. Acclimatization, which can take several weeks, enables your body to adjust gradually and cope better with the heat. Remember, taking it easy initially is crucial to your well-being.

Stay Hydrated to Prevent Heat Stroke and Heat Exhaustion

Staying hydrated is crucial for your health, especially when working in the heat. Aim to drink a cup of water (approximately 250 ml) every 15 minutes, which amounts to about one litre per hour. You will feel and perform much better if you drink water consistently throughout the day, rather than just during mealtimes or breaks. Remember to drink plenty of water before and after work as well, to ensure you are not dehydrated before starting your shift.

What Medicines and Drugs Increase the Risk of Heat Stroke?

Unfortunately, all medicines have some side effects. Some medications that may affect your ability to work safely in the heat are listed below.

• Blood pressure pills
• Beta-blockers
• Antidepressants
• Aspirin and other over-the-counter pain relievers

If you are working in the sun, antibiotics, antifungals, and acne drugs can heighten your sensitivity to the sun, leading to a bad sunburn.

Before working in the heat, talk to your doctor or pharmacist about any medicines you take.

Know Your Rights and the Regulations In Your Area

Different countries, states, and provinces have varying legal requirements regarding working in hot conditions. It is essential to familiarize yourself with the regulations specific to your area. In the United States, Europe, and Canada, employers are generally required to take reasonable precautions to ensure worker safety. Employees have the right to refuse unsafe work and should report any feelings of faintness, lightheadedness, coordination issues, or illness to their supervisor. Additionally, checking in on the well-being of co-workers is encouraged, as they may need assistance.

Guidelines and Regulations for Heat Exposure

Legislative requirements regarding work in the heat vary by Country, State, and Province. Some Jurisdictions have no maximum heat exposure limits beyond the legal obligation to keep workers safe; in contrast, California, Minnesota, Oregon, Washington, and British Columbia, Canada, have specific regulations. The province of Ontario is proposing a new stand-alone Heat Stress Regulation.

For example, California’s Heat Illness Prevention Standard for outdoor work requires employers to provide training, water, rest, shade, and planning. A temperature of 80°F triggers the requirements. At 95°F, more stringent requirements kick in. For indoor places of employment, the regulation will apply where the temperature reaches 82°F.

In Oregon, the Heat Illness Prevention Standard applies at a heat Index of 80°F. More rigorous requirements kick in at a heat index of 90°F.

“The Heat Index sometimes referred to as the apparent temperature or “feels like,” is given in degrees Fahrenheit and is a measure of how hot it really feels when relative humidity is factored in with the actual air temperature.”

The National Weather Service

The National Weather Service uses a heat index (HI) to classify environmental heat into four categories: Caution (80°F – 90°F HI), Extreme Caution (91°F – 103°F HI), Danger (103°F – 124°F HI), and Extreme Danger (126°F or higher HI).

Although it is not used in any regulations for heat exposure, you may also see the “Feels Like” temperature on the News or your Weather app. “Feels Like” temperature includes the effects of humidity and wind speed (but not direct sunlight) to adjust the actual temperature to help us understand how it feels outside. It’s a way to express the overall temperature sensation you experience on your skin when you step out.

The Wet Bulb Globe Temperature (WBGT) is considered a more accurate indicator of the effects of heat on individuals than just the temperature, Heat Index (HI) or “Feels Like” index. Wet Bulb Globe Temperature measures heat stress in direct sunlight, which considers temperature, humidity, wind speed, sun angle, and cloud cover (solar radiation).

See the chart below from the National Weather Service for some basic working guidelines using the WBGT.

The National Institute for Occupational Safety and Health (NIOSH) has set guidelines using the WBGT. The guidelines incorporate how much of each hour is worked (15 minutes per hour to 60 min./h.) and how hard the person works (100 to 500 Kcal/h).

A more straightforward method for measuring discomfort due to heat has been developed using the Humidex scale in Ontario, Canada. This scale combines temperature and humidity to assess perceived temperature. A Humidex level above 30 may cause discomfort for healthy adults, while levels exceeding 35 require a hot weather action plan. When the Humidex reaches above 40, all unnecessary activities should be avoided.

See the Occupational Health Clinics for Ontario Workers for a great humidex calculator that gives some basic safety measures to follow when the temperature gets hot.

If You or Someone Else Feels Sick From the Heat

Acting quickly is crucial if you or someone else experiences a heat-related illness. You want to lower the body temperature as soon as possible. Use as many of the methods listed below as you can.

• Move out of the heat to a cool area
• Place hands and forearms in cool water
• Place cool, wet towels or ice packs on the armpits and groin
• Spray with a garden hose or take a cool bath or shower
• Give cool liquids, but if the person is confused or unconscious, the drinking of liquids is not recommended

Try Our Free Heat Stroke Prevention Microlearning!
HEAT ILLNESS PREVENTION TRAINING: KEEP IT COOL.
Keep you and your family safe. Ensure everyone knows the signs and symptoms of heat exhaustion and heat stroke and how to keep cool. It takes less than 30 minutes!

If you work outside in the heat, you may also be exposed to the cold in the winter. Check out “When Is It Too Cold to Work?”

If you want more information on heat exhaustion and heat stroke, please visit the websites below.

• Video: Overview of Heat-Related Illnesses – The New England Journal of Medicine
• Occupational Safety and Health Administration – Working in Outdoor and Indoor Heat Environments
• National Integrated Heat Health Information System
• Heat stress information from the CDC
• Protecting Workers from Heat Stress, Quick Card from OSHA
• Humidex Rating and Work from CCOHS

How do you keep cool when the heat is high? Let us know.