July 31, 2002

Excessive Heat Could Cause A Disaster For You

By Maureen Alvarez
CIH, CSP

As we continue to work in the hot summer months, we must remind ourselves of the causes and dangers of heat related emergencies.  Heat waves and droughts take more lives than almost any other natural disaster in North American history. This fact should serve as a reminder of the importance of protecting ourselves from the effects of excess heat.

Heat stress occurs when the body has to work too hard to cool off. The body's core temperature gets too high for the body to cool off quickly enough. Heat stress symptoms include the following:

Heat Cramps

Heat cramps often occur in the legs and abdomen when a person is sweating heavily and replacing water but not salt. The skin is hot and moist and the pulse is normal.

Heat Cramps will often affect people who are doing strenuous activities in the heat resulting in a large amount of sweating.  The sweating depletes the body’s salt and moisture content.  The decrease in salt concentration in the muscles could cause painful cramps.  Employees who work outdoors during the summer months while performing heavy labor work such as construction are at risk of developing heat cramps.  Also, employees who perform work in personal protective equipment such as hazardous material crews are also at risk.

Heat Cramps may also be a symptom of Heat Exhaustion.

Heat Exhaustion

Heat exhaustion occurs when the body's heat control system is overtaxed. Symptoms of heat exhaustion include heavy sweating, paleness, muscle cramps, tiredness, dizziness, weakness, fainting, headache, nausea and vomiting.  During heat exhaustion the core body temperature is increasing and your normal body mechanisms of lowering that temperature cannot keep up.  Heat exhaustion may lead to Heat Stroke.

Heat Stroke

Heat Stroke occurs when the body’s cooling mechanism fails.  Heat stroke can cause death or permanent disability if emergency treatment is not rapidly provided.

Heat stroke is a serious emergency which requires immediate medical attention. It occurs when the body is rapidly using up its supplies of water and salt. Sweating stops and the body, including the brain, begins to overheat rapidly. Body temperature climbs to fatal levels. Symptoms include hot, dry, flushed skin, rapid pulse, difficulty breathing, headache, confusion and strange behavior, weakness and nausea. Heat stroke can rapidly progress to seizure and convulsions, unconsciousness and loss of pulse.

Who is at High Risk of Heat Stress Symptoms?

The following types of people are considered to be at high risk of heat stress:

• Employees that work strenuously outdoors
  
• Employees that work in a hot environment and/or are required to wear heavy, bulky clothing or personal protective equipment (i.e., Welders, Abatement workers, HazMat workers, Firemen, etc.
• Adults over 65 years of age

• People who are overweight or obese

• People who have high blood pressure

• People with heart disease, lung disease, diabetes, or have an infection causing a fever
• People who are on certain medications or have been drinking alcohol

The following are some tips for avoiding heat stress this summer:

• Follow work and rest routines which keep you from becoming exhausted in the heat. Alternate heavy work with lighter work, or move from a hot location to a cooler one periodically. If possible, schedule the heavy work for morning or late afternoon when it is cooler outside.  Take advantage of scheduled breaks to rest and cool off.


• Drink water frequently. One of the main causes of heat stress is dehydration, so keep up your intake of water or fluid replacement drinks. Don't wait until you are thirsty to drink. Avoid alcohol and caffeine beverages, which actually deplete the body of fluids.

If possible, put bottles of water in the work area so that water is readily available.  Try and pre-hydrate prior to any strenuous work or activity.

• Eat regular, light meals. Save the hot dinner until after work, and have something cool such as salad for lunch. If you are sweating a lot, lightly salt your foods to replace salt. However, if you are on a salt-restricted diet, seek medical advice about this. Salt tablets are not recommended.


• Take care when moving from a cool area to a hot one, such as leaving an air-conditioned workplace and stepping out into the late afternoon heat. Take time to get accustomed to the temperature, and slow down. Getting into a hot car can also be a shock to the system, so use ventilation to cool it down.
• Dress in loose, comfortable clothing made of light fabrics and in light colors. Layer your clothing so you can add and take off items of clothing as the temperature changes.
• People in poor health, overweight, tired, taking certain medications, older, or previous victims of heat stress, are more susceptible to heat illness.  Please take the time to identify your own personal limitations of working in the heat and monitor yourself carefully.

The treatment of heat stress depends on how serious it is:

• In the case of heat cramps move into the shade and loosen clothing. Drink lightly salted fluids (Gatorade, sports drinks, etc.)  Seek medical help if the cramps persist. Keep the victim sitting or lying down.
• For heat exhaustion, get the victim to a cooler shaded area. Loosen clothing, and begin cooling the victim quickly - by fanning him and pouring cool water on him if necessary. Have the victim drink water, salted if available.
• Heat stroke is a serious, life threatening condition and the person needs immediate medical help. Call an ambulance immediately, and begin cooling the victim as quickly as possible. Spray or sponge him with cool water or immerse him. Do not give liquids to an unconscious person.

Heat stroke is a life-threatening illness. Take steps to prevent heat illness, and treat all heat disorders seriously.

For more information about heat and sun hazards, visit the OSHA web page at www.osha.gov.  To help employers protect workers from the harmful effects of working in hot environments, OSHA offers a heat stress card – available in English and Spanish.  To order copies of the card, call OSHA Publications at (202) 698-1888.

Copyright © 2002 by WorkCare™ All Rights Reserved

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