Recognize and Prevent Heat-Related Illnesses
Posted: Aug 22, 2013
By Renee Witherspoon, MS, CSP, CIH, CHMM, ASSE South Plains Chapter President
According to the Centers for Disease Control and Prevention approximately 400 Americans die each year due to heat related illnesses. The National Weather Service states that excessive heat was the number one weather-related killer, causing more fatalities per year than floods, lightning, tornadoes, hurricanes, winter storms and extreme cold from 1994 to 2003.
Exposure to excessive heat can cause many safety challenges including increased accidents due to sweaty palms, dizziness or fogging of safety glasses. Working in hot environments can also decrease mental alertness and physical performance. With multiple days of triple-digit temperatures in Texas, utility professionals have to be able to recognize heat stress conditions, understand how our body responses to the heat (also called “heat strain”), and the basics of a heat stress program to prevent injury.
Recognition of Heat Stress Conditions
The combination of high heat and humidity can be a killer. When heavy workloads and personal protective equipment (PPE) are added, it can place an extra strain on the body. Each of us react differently when in hot environments and can depend on several factors including our age, weight, degree of physical fitness, degree of acclimatization, metabolism, use of alcohol or drugs, and a variety of other medical conditions including high blood pressure and heart disease.
The National Weather Service (NWS) issues heat alerts based on the Heat Index Values (see NOAA National Weather Service Heat Index graph). The Heat Index Value factors in actual temperature and relative humidity to give an index of what it actually feels like. This index then provides a likelihood of someone developing a heat-related illness with prolonged exposure or strenuous activity outside. Use this chart to determine if further heat stress prevention activities should be implemented.
The following are some risk factors for Heat-related Illness:
- High temperature and humidity, direct sun exposure with no breeze or wind
- Low liquid intake
- Previous heat-related illnesses
- Heavy physical labor
- Waterproof clothing
- No recent exposure in hot work areas or work outside during high heat conditions.
There are many types of Heat Stress-related illnesses ranging from mild to severe. Heat stroke is the most severe, and the one we are most familiar with. It occurs when the body is unable to regulate its temperature, the sweating mechanism fails and the body is unable to cool down. Heat stoke can cause death or permanent disability if emergency treatment is not provided immediately.
Our Body’s Response to Heat
Working in a hot environment is stressful on the human body. When exposed to heat the body tries to keep its internal temperature at about 98°F. And when the body temperature rises it cools itself through perspiration. If it is unable to keep up and dissipate the extra heat, vital organs such as the kidneys can shut down and cause damage to the central nervous system including the brain.
Heat exhaustion can be very mild with symptoms of headaches and dizziness. Irritability and confusion are additional symptoms of heat exhaustion. If someone passes out or collapses, call 911 and implement first aid procedures as it may have already escalated to a life-threatening condition.
Being alert to physical signs and symptoms of heat stress is a simple method to prevent a more serious injury.
If a worker becomes ill from the heat, the following are some basic procedures:
- Call a supervisor for help. If the supervisor is not available, call 911.
- Have someone stay with the worker until help arrives.
- Move the worker to a cooler/shaded area.
- Remove outer clothing.
- Fan and mist the worker with water.
- Apply ice (ice bags or ice towels) to the victim’s armpits, groin, neck, and back. (These areas are rich with blood vessels close to the skin, cooling them may reduce body temperature.)
- Provide cool drinking water, if able to drink.
Prevention of Heat Stress
Not only do we need to recognize the signs and symptoms of heat stress and how to treat symptoms, but we need to educate and train our personnel on how to prevent heat-related illness.
A simple program for Heat Stress may include:
- Implementing a good Heat Acclimatization Program that gradually adapts workers to the heat.
- Having workers wear light-colored, loose fitting and breathable clothing such as cotton.
- Monitoring the Heat Index so that hot jobs can be scheduled during cooler times of the day.
- Using engineering controls, such as cooling mist fans, air conditioners or shielding for hot sources.
- Providing plenty of cool liquid (except alcoholic beverages) and encouraging employees to drink small amounts frequently, every 15 to 20 minutes—rather than relying on thirst. Electrolyte drinks like Gatorade also work.
- Allowing workers to take rest breaks in cooler environments.
- Using power assists and tools that reduce physical demands.
- Utilizing body cooling devices, such as ice vests and wetted bandanas.
- Establishing a screening program to identify health conditions aggravated by exposure to heat stress.
- Providing training programs regarding the health effects associated with heat stress, symptoms of heat-related illnesses and the methods of preventing such illnesses.
Working in temperature extremes is just part of the job for a utility professional. As with other types of safety hazards, recognition of the signs and symptoms is a key. We should avoid exposure to extreme heat and high humidity if possible, and if it cannot be avoided be able to take the appropriate steps to prevent heat-related illness for ourselves and our coworkers.
Save a life—Never ignore signs or symptoms of heat strain.
NOAA’s National Weather Service Heat Index can be found at http://www.nws.noaa.gov/os/heat/images/heatindex.png
Heat Stress, NIOSH Workplace Safety and Health Topics, http://220.127.116.11/niosh/topics/heatstress/
OSHA Regional Notice: Region VI emphasis program for outdoor heat related health hazards, Directive 02-00-027, Effective date: October 1, 2010
WebMD, Heat Stroke: Symptoms and Treatment, http://www.webmd.com/a-to-z-guides/heat-stroke-symptoms-and-treatment
There are many additional resources on heat stress, acclimatization programs, exposure limits and measurement techniques not discussed in this article. If you would like additional information on setting up a program or would like a copy of my one-page Heat Stress Evaluation Checklist or Single Task Heat Stress Analysis sheet, send me an email at email@example.com