Heat Stress Management
What is Heat Stress?
Heat stress is the buildup in the body of heat generated by your muscles during work and by a warm or hot work environment. Heat stress correlates with heat illness which includes a number of disorders that occur when the body is subjected to more heat than it can expel. Heat illness causes a number of disorders when the body cannot cope with excessive heat.
The human body becomes weak when overheating occurs due to less blood flow going to the active muscles, organs, and the brain. Tiredness from heat stress causes a quicker onset of tiredness, lessened mental alertness, lack of clear judgement, and lesser quality work. The body temperature can rise rapidly and become severe without obvious symptoms such as pain. A 2 degree Fahrenheit rise in body temperature causes reasoning to become impaired, and a 5 degree increase causes severe heat stroke that is fatal 20% of the time. Victims of severe heat stroke can even suffer from long-term effects throughout their lifetimes.
There are many factors that cause heat stress, but there are several ways to combat heat stress in the work place and while exercising. Recognizing symptoms is the most important step in prevention of heat stress. Knowing how to perform first aid on victims of heat stress, heat illness, and heat stroke is a vital base of knowledge. More importantly, proper treatment of heat related conditions saves lives - plain and simple.
Heat Stress Factors
There are several circumstances that promote the risk of heat stress. These must be recognized and remembered in order to reduce the risk.
- Heat - This is pretty obvious, but as temperature, humidity, and sunlight increases so does the chances of heat stress. High humidity does not allow sweat to evaporate which increases body temperature. On the other hand, wind promotes evaporation of sweat and is productive in cooling down the body.
- Work Load - Hard work causes heat to build within the body. Heavy work loads increase the risk of heat stress. Working and exercising without taking regular breaks greatly increases the risk as well.
- Personal Protective Equipment - Extra clothing needed for a job, or gear required at a job site attributes to heat stress. Chemical resistant gear attributes greatly to the risk of heat stress, because it interferes with the body's ability to cool itself by preventing evaporation.
- Water Intake - Water is absolutely necessary to prevent heat stress. Evaporation of sweat lowers body temperature, but the sweat must constantly be replaced by drinking water. Drinking water very often will replace what is lost in sweat.
Early Heat Stress
- Sweating, headache, and fatigue.
Moderate Heat Stress
- Dry mouth and eyes
- Lack of saliva
Severe Heat Illness
- Fast Pulse
Extreme Heat Illness!
- Dilated pupils
- Loss of coordination
- Fainting and slow pulse
- Possibility of death
- Contact emergency services immediately!
Heat Stress Symptoms
There are several different levels of severity when dealing with heat stress. Each of these levels of severity must be recognized and watched closely. The severity of heat stress can increase so rapidly that the victim is unaware of the danger.
Sweating is the first sign of heat stress. Sweating is completely normal during physical exertion, as long as water intake replaces what is lost. Headache and fatigue follows sweating and many people are unaware of how fatigued they truly are.
The severity jumps much higher once the membranes of the mouth and eyes dry out. Dry mouth and lack of saliva is the onset of a serious problem. Fast pulse and nausea follow. A person may only begin to notice how severe the heat stress is once they begin to feel nauseous and ill. Very severe symptoms await, and the danger of death is very possible.
Severe symptoms such as dilated pupils, loss of coordination, confusion, and fainting (along with a slow pulse) prompt immediate medical attention. Alert emergency services!
Preventing Heat Stress
Knowing how to prevent heat stress is absolutely vital. There are several simple steps one can take to protect themselves and others during conditions that favor heat stress.
- Adapt to Conditions - The human body cannot quickly transition from a temperate environment to a very hot environment. The body needs time to acclimate to the conditions, and this can be done by working for only an hour or so in hot conditions each day for a week. This must be done before even attempting to perform a solid day of work. Many people who work outside acclimate to the conditions naturally, because they work through the changing seasons. Working throughout spring will prepare the body for summer.
- Account for the Heat - Plan tasks and exercising routines that require the most exertion during the coolest time of the day, which is usually early morning. Performing heavy exertion in the shade will cut back on heat stress risk as well. Always stay hydrated, even if the early morning hours are relatively cool.
- Appropriate Personal Protective Equipment (PPE) - Wearing PPE is required on many work sites and tasks. Do not wear more PPE than is required, and select the coolest and most aerated equipment. The same can be said for exercising by wearing only what is necessary.
- Stay Hydrated - Staying hydrated cannot be stressed enough. Drink plenty of water before, during, and after work or exercise. DO NOT wait until you feel thirsty. Large amounts of water can be lost before the body "feels" thirsty. Always drink enough water throughout the day to replace what was lost.
- Know Your Limits - Be able to recognize symptoms of heat stress and stop working/exercising immediately once symptoms occur. Stop activity until symptoms subside, while continuing to prevent heat stress by following the guidelines.
First Aid for Severe Heat Stress
Never waste time when dealing with severe heat stress, and contact emergency services immediately. Several things can be done before emergency personnel arrive. These steps save lives while awaiting medical support. Also, never let a victim go alone to a hospital or doctor when experiencing heat stress.
- Move the victim into a cooler or shaded area.
- Carefully remove any personal protective equipment and other clothing that is promoting the buildup of body heat.
- Cool the victim as quickly as possible by sponging and splashing cool water on the skin. Get the victim into a shower or bathtub if possible to increase cooling.
- Give cool water to the victim to drink. Have the victim drink as much of the cool water as possible. Never give an unconscious victim anything by mouth.
- Keep the victim relaxed and quiet. Panicking will cause the victim to lose more energy and vital water.
Heat Stress Symptoms and Treatment Overview
Early Heat Stress
Headache, fatigue, impaired judgement
Rest, drink water, remove excess clothing
Sickly, pale, nausea, fast pulse
Lie down, drink water, splash with cool water, move to cooler/shaded area
Severe Heat Illness/Stroke
Fainting, confusion, no sweating, convulsions, loss of coordination
Contact emergency services, vigorously splash with cool water, remove outer clothing, fanning, drink water if conscious