Beating the Heat

June 1, 2002
Health and Safety

Beating the Heat

When the mercury rises, will you be ready? asks Sara Garity

By Sara GarityBy Joan Bittel>

June/July 2002

Summer can be very hot on the ramp. Combined with the humidity, the temperature can reach the 100-degree mark. You feel yourself sweating, you're thirsty, exhausted, and maybe have a cramp in your side or leg, but, you think to yourself, I only have a few more hours of work left. So, you continue to work as your body temperature continues to rise.

Stop what you are doing! Heat stress is a serious medical condition and causes exhaustion, cramping, fainting, rashes — even death. So, before you begin to ignore the headaches, thirst, and the nauseous feeling in the pit of your stomach, you need to know what to look for and how to prevent yourself from becoming the next heat stress victim.

Heat stress is caused by excessive exposure to heat and can lead to a number of heat-related illnesses ranging from mild (prickly heat) to life-threatening (heat stroke). Body temperature depends on a balance between heat created and lost. If heat production is increased, through intensive or enduring work, the body must be able to lose the extra body heat it is generating. The body naturally does this through sweating, but sometimes that isn't enough. You need to be able to identify the symptoms and take action immediately.

According to the Occupational Safety & Health Administration (OSHA), several factors can contribute to heat stress.

  • Outside temperature
  • Humidity
  • Air movement
  • Radiant temperature of your surroundings
  • Amount and type of clothing worn
  • Amount of physical activity

However, age, weight, fitness level, medical condition, and body's personal tolerance to heat are often overlooked, but have a major effect on how your body will react in extreme heat situations. Persons with a low fitness level and low heat tolerance may not be used to and may not be able to rid themselves of the excess heat generated. Generally speaking, persons that are overweight, or are older, may not be used to heavy work environments and may be unable to acclimate to their surroundings fast enough to prevent health problems.

There are plenty of products on the market that can help make your workday as comfortable as possible. Camelbak Company offers several personal hydration solutions. Their Hi-Viz vests are designed with an insulated bite valve cover that keeps the device clean, while the closed-cell insulation keeps the water cold for hours. The external fill reservoir makes filling fast and easy. The vests are available in orange and lime green, complete with reflective strips and a harness.

Delta Temax Inc. (DTI) has developed Personal Ice Cooling Systems (PICS). PICS use ordinary ice water as a coolant that is circulated through tubing into a durable, full-body garment that weighs 12 pounds. An adjustable-rate, battery-powered pump circulates chilled water through the tubing in the suit, enabling the wearer to control the rate of cooling.

MiraCool bandanas from CoolSport stay hydrated for several days, are reusable, and work without or ice. Just soak the bandanas in water for 30 minutes and wear.

The Vital Sense Heat Stress Monitoring System by Mini Mitter offers the latest in monitoring technology. While other monitoring systems keep track of the environment, the Vital Sense is an online physiological monitory system. Vital Sense can monitor the temperature, heart rate, skin temperature, and activity data of up to ten individuals in real-time. The sensors calculate several times per minute and can alert the worker or supervisor if any problems occur.

If monitoring equipment is not available, use a clinical thermometer for a quick vitals check. Normal human body temperature is around 98.6 degrees F. You can also measure body water loss with a bathroom scale. By weighing a person on a scale before and during working hours, you can determine whether or not a person is dehydrated. If weight loss exceeds 1.5 percent, fluid intake should increase. Other signs of dehydration include dry nose and mouth, fatigue, irritability, headaches, loss of balance, and darkly-colored urine.

When the weather gets warmer, working conditions heat up. Heat stress is a serious medical condition that can cause severe health risks if not taken seriously. You need to listen to your own body. Are you able to recognize the signs of heat stress? Will you know what to do if someone becomes ill? Knowing the answers to these questions may save a life. What if it's your own?


  • Heat Rash (Prickly heat): Occurs when sweat is not removed from the skin. Skin appears red and itchy.
  • Heat Syncope (Fainting): Occurs when standing for long periods of time.
  • Heat Cramps: Occurs abruptly like a "Charlie horse", may last for extended periods.
  • Heat Exhaustion: Occurs when there is a loss of fluid. Person feels weakness or fatigue, giddiness, nausea, or headache. Skin may become clammy or moist, complexion becomes pale or flushed.
  • Heat Stroke: Occurs when internal temperature mechanism fails. Person usually stops sweating and experiences mental confusion, delirium, and loss of consciousness. Body temperature reaches 106 degrees Fahrenheit.


  • Heat Rash (Prickly heat): Rest in a cool place and allow the skin to dry.
  • Heat Syncope (Fainting): Lying down. (Can be prevented by moving around while working.)
  • Heat Cramps: Cramps are caused by loss of electrolytes. Drink a sports-type drink with electrolytes.
  • Heat Exhaustion: Rest in a cool place and drink electrolyte liquids.
  • Heat Stroke: Call medical help. Move to cool area. Soak clothes with cool water. Fan vigorously.


  1. Drink at least 2 liters of water a day, more if sweating.
  2. Acclimation: Introduce new workers gradually. A body needs time to learn to lose heat efficiently.
  3. Provide shade and air movement (fans): Shade reduces radiant heat and fans increase sweat evaporation.
  4. Schedule hot jobs for cooler parts of the day.
  5. Provide cool rest areas where possible: These enable a rapid return of core temperature to normal. Air conditioning can lower both temperature and humidity.
  6. Wear light clothing and sun protection: Heavy clothing prevents body heat from evaporating.
  7. Diet: Eat appropriately. Too much salt can cause dehydration. Avoid alcohol. Drink plenty of liquid electrolytes.
  8. Be careful: Excessive heat may reduce work capacity and efficiency.

    Source: Queensland Workplace Health & Safety -