HEAT STRESS by dffhrtcv3


									HEAT STRESS

      Heat Sources
        Prepared by Paul Young

   Temperature
   Humidity
   Radiant Heat
   Air Velocity
   All of these have an effect on the human
    body and the amount of stress that is

      Skin Temperature
        Prepared by Paul Young

   The body reacts to external temperature by
    circulating blood to the skin. This increases
    epidermal temperature and allows the body
    to give off excess heat through the skin.

   If the muscles are being used for physical
    labor, less blood is available to flow to the
    skin and give off heat.

        Prepared by Paul Young

   “Men sweat, women perspire, ladies merely
    glow,” or so said a southern belle in a time
    of extreme stress.
   Sweating is another mechanism the body
    uses to regulate internal temperature.
   This is effective only if the humidity level is
    low enough to permit evaporation, and if
    lost fluids and salts are replaced properly.

         Effects of heat
            Prepared by Paul Young

   If the body cannot shed excess heat, it stores the heat internally.
   As the body’s core temperature rises, there is an increase in heart
    rate and other effects may occur, depending on temperature, physical
    activity rate, humidity, etc.
   As core temperature increases, individuals may experience:
       Lost concentration
       Difficulty focusing on tasks
       Irritability
       Sickness, vomiting
       Loss of desire to drink fluids
       Fainting
       Unconsciousness

       Death

       Prepared by Paul Young
                           Air Temperature
Relative   70  75    80    85    90    95   100 105 110
Humidity    Apparent Air Temperature (Degrees Fahrenheit)
  0%       64  69    73    78    83    87   91    95   99
  10%      65  70    75    80    85    90   95   100 105
  20%      66  72    77    82    87    93   99   105 112
  30%      67  73    78    84    90    96   104 113 123
  40%      68  74    79    86    93   101 110 122 137
  50%      69  75    81    88    96   107 120 135 150
  60%      70  76    82    90    100 114 132 149
  70%      70  77    85    93    106 124 144
  80%      71  78    86    97    113 136 157
  90%      71  79    88    102 122 150 170
 100%      72  80    91    108 133 166

        Calculating Heat Index
           Prepared by Paul Young

   Check the weather forecast:
       Find today’s forecast high temperature
       Find today’s expected humidity.
   On the chart:
       Temperature is across the top of the chart
       Humidity is down the left side.
   Cross the two values to find today’s apparent temperature.
   Remember that these values are for shaded areas with
    light wind conditions. Exposure to full sun will typically
    increase these values by 15°. Working on hot asphalt will
    also add 10°. Strong winds, especially hot, dry winds, also
    increase hazards because of the drying effect on the skin.

        Dangers related to heat stress
          Prepared by Paul Young

   Heat Index 90 to 100 degrees:
       Sun stroke, heat cramps and heat exhaustion are
        all possible with prolonged exposure and
        physical activity.
   Heat Index 105 to 129 degrees
       Sun stroke, heat cramps and heat exhaustion are
        all likely.
       Heat stroke is possible with prolonged exposure
        and physical activity.
   Heat Index 130 and above
       Heat stroke is imminent.

            Heat Exhaustion
               Prepared by Paul Young

   Symptoms:
        Headaches; dizziness; weakness; mood changes; upset stomach;
         vomiting; fainting; pale, clammy skin.

   What to do:
        Act immediately. If not treated, heat exhaustion can quickly become
         heat stroke.
        Move the victim to a cool, shaded area. Don’t leave the victim alone.
         If symptoms include dizziness or lightheadedness, lay the victim on
         his or her back and raise the feet 6 to 8 inches. If symptoms include
         nausea, lay the victim on his or her side.
        Loosen or remove heavy clothing.
        Have the victim drink a cup of cool water every 15 minutes.
        Cool the victim by fanning or spraying
        If the there are no signs of recovery after 15 minutes, call 911.

         Heat Stroke
            Prepared by Paul Young

   Symptoms:
       Dry, pale skin with no sweating; hot, red skin that looks sunburned;
        mood changes; seizures or fits; unconsciousness with no response.
   What to do:
       Call 911 immediately.
       Move the victim to a cool, shaded area and lay the person
        on his or her back.
       Loosen and remove any heavy clothing.
       Have the person drink a cup of cool water every 15 minutes
        (if conscious).
       Cool the body by fanning or spraying with a cool water mist, damp
        cloths or a wet sheet.
       Place ice packs under the armpits and in the groin.

          Prepared by Paul Young

   Electrolytes can take two forms:
       Simple inorganic salts of sodium, magnesium,
        potassium or calcium.
       Complex organic molecules.
   Electrolytes flow through muscle cells to
    help maintain the normal cell function.
   Electrolytes are lost through perspiration
    and urination, and this depletes muscle
    cells and weakens the muscle tissue.

    Fluid intake
      Prepared by Paul Young

 While it is important to replace body fluids
  through drinking adequate quantities of
  cool water, this does not replace those
  valuable electrolytes.
 Water is still “nature’s perfect drink”, but
  studies have shown that electrolyte
  replacement products are absorbed
  faster in the first minute after intake.

         Prepared by Paul Young

   While involved in physical activity, especially as
    the temperature increases, most people
    experience the sensation of thirst, and drink
    water or other fluids to offset this sensation.

   As heat stress increases, many people lose the
    sensation of being thirsty, and so they don’t
    replace the lost fluids, leading to dehydration
    and the other harmful effects of heat stress.

    Types of Fluid
        Prepared by Paul Young

   Fluids that help quench thirst:
         Water
         Sports drinks like Gatorade
         Electrolyte replacement drinks

   Fluids that DON’T help quench thirst
         Carbonated drinks (soda pop)
         Caffeinated drinks (soda pop, coffee, tea)
         Alcoholic drinks (beer, wine)

         Prepared by Paul Young

   Taste has a marked effect on how employees
    help prevent dehydration.
   Not too long ago, employees exposed to high
    levels of work-related heat were required to
    drink salted fruit juices and other poor tasting
   Modern electrolyte replacement fluids have a
    taste that many people prefer to water.
   If people prefer the taste, they will be more
    likely to drink the fluid.

        The Buddy System
          Prepared by Paul Young

   As in many other work-related hazardous
    situations, it’s important that we look out for
    ourselves and each other:
       Always be aware of your own thirst. Drink when you
        feel thirsty. Working in direct sun on a hot day, you
        need about a quart of fluid every hour to replace what
        you lose through perspiration, etc.
       Watch your crew mates. If you see any signs of heat
        stress, encourage the team member to drink water or
        electrolyte replacement fluids.
       Notify your crew boss if you see a fellow worker
        exhibiting signs of heat stress.

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