1. CAP Ground Team - Task O-0003 Prevent & Treat Hot Weather Injuries Revision January 2012

2. Prevent & Treat Hot Weather Injuries(Task O-0003)
Reference:
Ground & Urban Direction Finding Team Tasks (24 May 2004)
Ground Team Member & Leader Reference Text (Revised Arpil 2003)

3. Objectives
Take steps to prevent hot weather injuries and recognize and treat those that do occur.

4. PROBLEMS DUE TO HOT WEATHER
Hot climate degrades physical performance and places each member of the team at risk for heat illness.
The risk of heat illness depends on physical activity, hydration, heat acclimatization, clothing, load carried, terrain, and climatic conditions.
Leaders must watch their team carefully for signs of distress in the heat and adjust work/rest schedules, work rates and water consumption according to conditions.

5. SWEAT
In very hot conditions, sweating is the only mechanism for heat loss.
Water must be consumed to replace the body's loss of sweat. If the body water lost through sweating is not adequately replaced, dehydration will follow.
Dehydration will lead to heat illness.
Heat, high humidity and exposure to the sun all tend to increase body temperature and increase water requirements, primarily through loss of body water as sweat.
Sweat rates can be high even when the skin looks and feels dry, since sweat evaporates very quickly in dry air.

6. DEHYDRATION
Dehydration cancels the benefits of heat acclimatization, increases the risk of heat illness, reduces work capacity, appetite, and alertness. The greater the dehydration the more severe the effects.
Thirst is a poor indicator of dehydration. Ground team members in the field do not sense when they are dehydrated and usually do not replace body water losses, even when drinking water is readily available.
Personnel under stress in hot environments will exhibit "voluntary dehydration". They maintain themselves about 1.5 quarts below their ideal hydration status without any sense of thirst.
Ground team members must consciously remind themselves, or be reminded to replace water lost to sweat.
Ensuring regular consumption of fluids is the responsibility of the unit leader.

7. Your whole body suffers when your thirsty

8. How Heat Affects Performance
Heat degrades mental performance as well as physical performance.
Rested, well-trained team members working on sedentary tasks should be able to work normally in the heat for up to four hours, after that mental performance will steadily deteriorate.
Tasks which require sustained attention (e.g., site security) will be affected more quickly.
Performance in the following jobs will be affected by heat stress: monotonous, repetitive, or boring tasks; tasks which require attention to detail and short-term memory (e.g., calculations, map plotting, passing formal messages, etc.); tasks which must be done quickly or according to a fixed schedule; tasks which require arm-hand steadiness; command and operations tasks where confusion and misinformation are common.
Reaction times and decision times are slower in the heat.

9. “…heat is by far the number one killer of all weather events…”
Although rarely recognized, heat is by far the number one killer of all weather events. Over the last ten years, heat has averaged nearly 170 fatalities a year.
In 2006, 253 people died as a result of extreme heat, up from 158 fatalities in This number is well above the 10-year average for heat related fatalities of 170.
Extreme heat affects all, but the elderly, poor, infants and those who work outside during the summer are the most likely to succumb to the heat.
“…heat is by far the number one killer of all weather events…”
Courtesy NOAA’s National Weather Service

10. Heat Stress Prevention
Heat injuries (sometimes called heat stress) are the result of overexertion and dehydration.
These conditions can occur at any time during the year, but are most common during the summer months with high temperatures and humidity.

11. Control of Problems due to Hot Weather
The key to preventing heat illness and sustaining performance is knowledge of the environmental conditions.
Leaders must have accurate weather information for their specific location.
If members are not fully acclimatized, adequately fed, rested and hydrated, the amount of cooling and rest provided during each work period needs to be increased.

12. Acclimatization & Physical Fitness
Attain the best possible physical fitness and heat acclimatization prior to missions. Physically fit personnel acclimatize to heat more rapidly than those less fit.
Units on alert, or identified for long term missions, should emphasize their physical training program and state of heat acclimatization (e.g., spend more time exercising in the heat where possible).

13. Acclimatization & Physical Fitness (continued)
Significant acclimatization to heat can be attained in 4-5 days. Full heat acclimatization takes 7-14 days with 2-3 hours per day of carefully supervised exercise in the heat.
Increase physical activity each day until full acclimatization is achieved.
Acclimatization requires that progressively more physical activity be performed each day. During the first two days of heat exposure, light activities such as recreation activities or short training missions would be appropriate. Leaders should gradually increase the intensity of exercise each day working up to an appropriate physical training schedule adapted for the environment.

14. Acclimatization & Physical Fitness (continued)
Acclimatization does NOT reduce and may actually increase water requirements. Heat acclimatization increases sweating to enhance the evaporative cooling capacity of the body. Increased sweating requires additional water consumption. It is dangerous and inappropriate to try to reduce water consumption.
Personnel may have a few days of increased salt requirements upon initial deployment because sweat is salty prior to acclimatization. Complete consumption of rations with use of salt packets is essential to provide an adequate salt intake. Salt supplementation is not appropriate unless medically indicated and supervised by medical personnel.

15. HYDRATION
Leaders must understand the critical importance of maintaining hydration. Almost any contingency of military operations will interfere with the maintenance of hydration.
Establish mandatory drinking schedules which replace water lost by sweating.
Plan operations to provide water re-supply points at a maximum interval of every three hours. One-hour intervals are more desirable. Carry as much water as possible when separated from approved sources of drinking water. Insure members always have at least one full canteen in reserve; know when and where water re-supply will be available. Personnel can live longer without food than without water.

16. HYDRATION (continued)
Minimize voluntary dehydration by making flavored, cool water accessible in a comfortable place, and providing enough time to drink and eat. Before flavoring water, be sure that it is potable. Flavoring in individual canteens should be avoided; it increases the risk of contamination and illness.
Carbohydrate/electrolyte beverages (sports drinks) are not required, and if used should not be the only source of liquid.
Drinking water does more good than splashing it on the skin. Water splashed on the skin is wasted water; it might briefly improve comfort, but does little to sustain performance and avoid heat illness.

17. Clothing, Equipment & Supplies
Change socks when they become soaked with sweat. Prolonged wear of wet socks can lead to foot injury (e.g, increased risk of blisters).
Sweat accumulation in the boot can be reduced by wearing a sock that is absorptive and thick enough to "wick" moisture away from the foot and toward the top of the boot where evaporation can occur.
Find a sock combination that works well for you, but remember that cotton athletic socks are a no-no.
Some people find that one pair of synthetic socks works best for them, some find that two pairs is better, some find that a thin inner sock and a thick outer sock works. Whatever you choose, make sure your boots are correctly fitted for you with the socks you will be wearing.

18. Clothing, Equipment & Supplies (continued)
Uniforms should be worn to protect against sun, wind and insects. Wear the uniform properly, blouse trousers and roll down sleeves. Use hats, head cloths and sunscreen. Heat strain will be reduced by shielding the body from the sun. Wearing Hot Weather Battle Dress Uniform reduces water requirements by limiting heat gain.
Because clean clothing protects better and prevents skin rashes, whenever possible, wash clothing and air-dry or sun-dry if in the field for extended periods.

19. Heat Rash & Sunburn
Heat Rash: a skin rash most commonly found on clothed areas of the body. Heat Rash can impair body heat loss and degrade performance for many days after it's disappearance. Heat rash can be avoided by practicing good hygiene and keeping skin clean and dry.
Sunburn impairs body heat loss, degrades performance and increases the risk of heat casualties. Sunburn can be avoided by protecting skin with clothing and sunscreen. Emphasize the importance of hats and long sleeves.

20. Preventing Heat Stress
Drink enough water!
Two quarts per day is the absolute minimum on a mild day. On a hot summer day, drink 6-8 quarts a day or 1 quart an hour. Frequent sipping is better than trying to drink an entire quart at one time
Monitor the color of your urine!
It should be almost clear in color. If it is brown or dark yellow, you are becoming dehydrated
Wear loose fitting and open clothing

22. Preventing Heat Stress (continued)
Don’t overexert yourself. Know your limits and do not exceed them. Take frequent breaks
Avoid sunburn by using sunscreen or keeping your sleeves down.
Watch other members of the team for beginning signs of heat stress. Immediately stop, rest and drink some waterl Once a person suffers from a heat injury, he or she will not be back for the rest of the day
Use the buddy system -- Assign everyone a partner to watch for heat stress and to monitor water intake

23. SUNSCREEN
Sunscreen should also be applied at least 30 minutes before going outdoors.
A common mistake is applying too little sunscreen, which can drastically reduce the effective SPF (Sun-Protection Factor). In addition, sunscreen must be reapplied at least every two hours when staying outdoors for a prolonged period of time.
People with sensitive skin who burn quickly and must spend a lot of time outdoors should always apply a sunscreen with an SPF of 30 or more.
Also, don’t forget to put and keep sunscreen on your ears, the back of your neck, as well as the tops of your hands and feet.

24. Factors used to Assess Heat Stress Risk
The 3 Factors that we are going to be discussing in the next few slides are:
Personal Risk Factors
Work Factors
Environmental Factors
Reference: Construction Safety Association of Ontario

25. PERSONAL RISK FACTORS Weight Poor Physical Condition
If you are overweight you are less efficient at loosing heat.
Poor Physical Condition
If you are not in good physical condition, your body is less able to cope with the demands that heat places on your body.
Previous Heat Illness
You are more sensitive to heat if you have experienced a previous heat-related illness.
Age
As the body ages, its sweat glands become less efficient

26. PERSONAL RISK FACTORS (continued)
Heart Disease or High Blook Pressure
In order to pump blood to the skin and cool the body, the heart rate increases, which causes stress on the heart.
Recent Illness
Illnesses with diarrhea, vomiting or fever increase the risk of dehydration
Alcohol Consumption
Alcohol consumption during the previous 24 hours leads to dehydration
Medication
Certain medications may cause heat intolerance. You should check with your doctor
Lack of Acclimatization
When exposed to heat, it takes approximately 6-7 days for your body to adapt

27. WORK FACTORS Clothing and Personal Protective Equipment (PPE) Workload
Heat Stress can be caused or aggravated by wearing PPE suites. Remember that coated and non-woven materials block the evaporation of sweat, which is needed to cool the skin.
Workload
The body generates more heat during heavy physical work. Heavy physical work requires special evaluation even at temperatures a low as 74° to prevent heat disorders. This is especially true for those who have not acclimatized to the heat.

28. ENVIRONMENTAL FACTORS
Let’s first understand that measuring the temperature is only one factor in what helps us to measure the “true” temperature as it affects our body.
The following are two examples which show why we need more information then just what the temperature is.
Example 1: It is noon and 100°. You are sitting under a shaded tree with a nice wind blowing and low humidity (amount of moisture in the air).
Example 2: It is noon and 100°. You are walking in the desert with no wind blowing and high humidity.
Even though the temperature is the same in both examples; I bet you could handle Example 1 for a lot longer then Example 2.

29. ENVIRONMENTAL FACTORS (continued)
Radiant Heat
Radiation is the transfer of heat from hot objects through air to the body. Working around heat sources will increase heat stress. Additionally, working in direct sunlight can substantially increase heat stress. You will be far more comfortable working at 93°F under cloudy skies than working at 93°F under sunny skies.
Humidity
Humidity is the amount of moisture in the air. Heat loss by evaporation is hindered by high humidity but helped by low humidity. As humidity rises, sweat tends to evaporate less. As a result, body cooling decreases and body temperature increases
Air Movement
Air movement affects the exchange of heat between the body and the environment. As long as the air temperature is less than your skin temperature, increasing air speed can help you stay cooler by increasing both the rate of evaporation and the heat exchange between the skin surface and the surrounding air.

30. Putting the Factors Together
While we can identify the Personal Risk Factors and the Work Factor; the question comes up with combining the Environmental Factors.
Have no fear….. There is a way to assess the Environmental Factors. It is the:
Wet-Bulb Globe Temperature Index (WBGTI)

31. WBGTI
The Wet-Bulb Globe Temperature Index (WBGTI) takes into account four variables:
Air Temperature
Humidity
Radiant Heat
Air Movement
This reading gives a more accurate measurement of heat stress than any one reading alone.

32. On the next slide you will see a “Fluid Replacement and Work/Rest Guide/Chart”
You will notice that the chart takes into consideration the WBGTI reading as well as the type of work you are doing and gives a “Heat Category”

33. Fluid Replacement and Work/Rest Guide
The work-rest times and fluid replacement volumes will sustain performance and hydration for at least 4 h of work in the specified heat category. Fluid needs can vary based on individual differences (± ¼ qt/h) and exposure to full sun or full shade (±¼ qt/h).
NL= no limit to work time per hour.
Rest means minimal physical activity (sitting or standing), accomplished in shade if possible.
CAUTION: Hourly fluid intake should not exceed 1½ quarts…… Daily fluid intake should not exceed 12 quarts.
Easy Work = Walking hard surface 2.5 mph <30# load
Moderate Work = Patrolling, Walking sand 2.5 mph no load, Calisthenics
Hard Work = Walking sand 2.5 mph w/load

34. Using the: Fluid Replacement and Work/Rest Guide
In Civil Air Patrol they will tell you what the Heat Category is (ex: 1,2,3,4 or 5) or they will tell you what flag condition you are under (ex: white, green, yellow, red or black). The Heat Category is based on the WBGTI.
Depending your work load and the Heat Category, you will be able to note your work/rest time & fluid intake.
Example: Red Flag & you are doing moderate work … You need to work 30 minutes and then rest 30 min. You also need to ensure you are drinking at least 3/4 quart of water every hour.
Note: When you see “NL” on the chart it means “No Limit”

35. TYPES OF HEAT INJURIES

36. There are three major types of heat injuries:
HEAT CRAMPS (caused by loss of salt)
HEAT EXHAUSTION (caused by dehydration)
HEAT STROKE (shock).

37. HEAT CRAMPS
Causes Heat Cramps are usually the first stage of heat streess. Heat Cramps are the result of dehydration and loss of electrolytes in body tissue. This normally happens after exercise. Most often to people who aren’t used to the heat, who sweat a lot or don’t drink enough fluids.
Symptoms
Severe muscle cramps, usually in the legs and abdomen
General weakness
Sometimes dizziness or faintness
a) Move the patient to a cool, shady place.
b) Provide salted water or a commercial electrolyte (i.e. Gatorade).
c) Massage the cramped area.
d) Apply some pressure to the cramped area, but stop if it makes the patient more
uncomfortable.
e) Apply moist towels to the patient’s forehead and the cramped muscle.
f) If symptoms worsen, immediately transport the person to a medical care facility.
Treatment
Move the patient to a cool, shady place
Increase fluid intake (salted water or electrolytes --- Gatorade)
Massage & apply slight pressure to cramped area
Use moist towels on forehead and cramped muscle
Immediately transport to medical care facility if symptoms worsen

38. HEAT EXHAUSTION
Causes Heat Exhaustion is the 2nd phase of heat stress (although some individuals may never develop heat cramps before going into heat exhaustion). This is caused by the loss of body fluids and important salts due to overexposure to high temperatures and humidity. Usually you are exposed to heat for a prolonged amount of time and you become dehydrated.
Symptoms
Rapid & shallow breathing
Weak pulse
Cold & clammy skin
Heavy perspiration
Weakness/dizziness that may lead to unconsciousness
Heat exhaustion is the next phase of heat stress (although some individuals may never develop heat cramps before going into heat exhaustion).
Heat Exhaustion starts with the accumulation of large quantities of blood in the skin in the body’s attempt to increase it’s cooling efficiency.
This is normally due to temperature conditions the individual is not used to.
There is a loss of circulating blood volume in the body which decreases the blood supply to the brain, increasing the likelihood of fainting.
Treatment
Move patient to cool, shady place & keep him/her at rest
Remove/loosen clothing to cool (not chill) the patient
Fan skin to promote sweat evaporation
If conscious provide salted water or a commercial electrolyte --- i.e. Gatorade.
Treat for shock and transport to a medical care facility
If left untreated Heat Exhaustion can lead to HEATSTROKE.

39. HEAT STROKE
Causes Heat stroke is the final phase of heat stress. It is a life threatening condition. It is the result of the body’s absolute failure to regulate heat, and as a result the bodies core temperature starts to rise (hyperthermia). This leads to the rapid destruction of body tissues and brain cells. Permanent brain damage and death are posible outcomes of Heat Stroke. Even if successfully treated, it will take days for the patient to recover.
Symptoms
Deep breathing becoming progressively shallower.
A rapid, strong pulse becoming weaker.
Dry and hot skin
Dilated pupils.
Possible unconsciousness, seizures, and muscular twitching.
Heat Stroke is the final phase of heat stress. It is a life-threatening condition. It is the result of the body’s absolute failure to regulate heat, and as a result the bodies core temperature starts to rise (hyperthermia).
This leads to the rapid destruction of body tissues and brain cells. Permanent brain damage and death are possible outcomes of heat stroke. Even if successfully treated, it will take days for the patient to recover.
The underlying cause of heat stroke is connected to the sudden inability to dissipate body heat through perspiration.
When treating a Heat Stroke victim the key is to cool the patient as rapidly as possible. Any cold liquid should be used to cool the victim.
Treatment
Remove the person from any heat sources and remove clothing
If possible immerse patient in cool water, or use cold wet towel or ice packs in the patient’s armpits, groin, under neck and behind knees. The key is to cool the patient a rapidly as possible.
TREAT FOR SHOCK AND TRANSPORT TO MEDICAL CARE IMMEDIATELY.
DO NOT give medication to lower fever, DO NOT use an alcohol rub.

40. HEAT STROKE Step One Evaluate for heat stroke
If you suspect heat stroke, treat as follows: .
Step Two
Move the patient out of direct sunlight,
preferably into a cool, shaded area

41. Have the patient lie flat and elevate his or her feet.
Step Three
Have the patient lie flat and elevate his or her feet.

42. Remove heat-retaining clothing
Step Four
Remove heat-retaining clothing

43. Wet the patient down and fan him or her,
Step Five
Wet the patient down and fan him or her,
or immerse the patient in cool water.
Step Six
Place ice packs on the patient's head,
back of the neck, armpits, palms of the hands,
soles of the feet and groin.

44. Step Seven
Hydrate well with lots of water, a diluted sports drink or oral rehydration solution, but only if the patient is conscious enough to hold a cup and drink unassisted.

45. Monitor body temperature frequently:
Step Eight
Monitor body temperature frequently:
Keep careful notes on how long the patient remains at a given temperature.
Transfer these notes when you transfer care.
Step Nine
Evacuate immediately
Continue monitoring and writing down the patient's body temperature.
Tips & Warnings
A person suffering from heat stroke is likely to have an unstable body temperature even after the body has cooled, so be alert for either hypothermia or an escalating temperature.
If you've immersed the person in cool water, remove him or her and fan once body temperature reaches 102 degrees or lower.
Evacuate immediately, even if the person appears to be recovering.
Don't administer heat-reducing medications.
Don't use salt tablets to rehydrate, as these are too concentrated. Use oral rehydration salts instead

46. Please click here to begin your online review questions
SUMMARY
By now you should be able to take steps to prevent hot weather injuries and recognize and treat those that do occur.
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47. This concludes the training for this task.
More resources are available on the SWR ES Training Website.