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My Life Monday
Doing too much on a hot day, spending too much
time in the sun or staying too long in an overheated
place can cause heat-related illnesses.
Heat attack
Hot temperatures and high humidity stress the body’s
ability to cool itself, resulting in heat sickness. It is
important to recognise the symptoms at an early stage
in order to guard yourself from serious consequences.
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• Dehydration-is the loss of fluids from the body. The
human body needs water for vital organs such as the
brain, kidney and heart to function properly.
• Heat rash- is a skin irritation caused by excessive
perspiration.
• Heat cramps- are severe and painful cramping of
the muscles due to imbalances in body fluids
and excessive perspiration.
• Heat syncope or fainting- dizziness that can
result in fainting when standing continuously
under the hot sun for a long time.
Know the difference
It is important to note the difference between various
heat illnesses.
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Heat exhaustion- results when losing body fluids
through perspiration during heat exposure.
The body cools off by evaporation of sweat but
gets exhausted when the sweat exceeds the
volume of water or fluid drunk.
Sun burn- is a painful skin condition which occurs
as a result of overexposure to the ultra-violent
rays of the sun. This can damage the outer layers
and inner tissues of the skin. It can also lead to
skin cancer.
Heatstroke or sunstroke-is a deadly heat illnesses.
It occurs when the body’s control temperature
system stops functioning. The body temperature
rises rapidly, the sweating mechanism fails and
the body is unable to cool down. This can lead
to death, brain damage or permanent disability if
emergency treatment is not provided.
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How to recognise, treat and avoid heat
illnesses?
Type Symptoms Treatment
Dehydration
1. Flushed face
2. Extreme thirst, more than
normal or unable to drink
3. Dry, warm skin
4. Dizziness made worse when
you are standing
5. Weakness
6. Cramping in the arms and legs
7. Headaches
8. Dry mouth, dry tongue
9. Low blood pressure
10. Rapid and deep breathing -
faster than normal
11. Fainting
For mild to
moderate
dehydration
drink more
water and try
to avoid the
heat until
refreshed.
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Type Symptoms Treatment
Heat Rash
1. Redness accompanied
with swelling and
inflammation of skin.
2. Small blisters.
Both symptoms commonly
occur on the back of the
neck.
The best treatment is
to provide a cooler and
less humid environment.
Clean the affected area
and apply mild lotions
to it.
Heat Cramps
1. Muscle pain in the
abdomen, arms or legs
may occur in association
with strenuous activity.
2. Rapid heartbeat
3. Hot sweaty skin
Stop all activities and
do not return to
strenuous activities until
the cramps subside as
further exertion may lead to
exhaustion or heat
stroke This usually
improves with drinking
water and resting in a
cool environment.
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Type Symptoms Treatment
Heat Syncope
Or Fainting
1. Faintness
2. Dizziness
3. Headaches
4. Increased pulse rate
5. Restlessness
6. Nausea
7. Vomiting
8. Possibly even a
brief loss of
consciousness.
Lie or sit down, preferably in
the shade or in a cool
environment.
Try to take frequent breaks if
working under high
temperatures and drink a lot
of water.
Heat
exhaustion
1. Headaches
2. Paleness
3. Heavy sweating
4. Intense thirst
5. Dizziness
6. Fatigue
7. Nausea
8. Impaired judgment
9. Loss of appetite
Shift to a cooler location and
drink a lot of water or a light
juice.
Use cold towels over your
head and neck.
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Type Symptoms Treatment
Sunburn
1. Skin becomes red
& painful
2. Burning sensation
and swelling
3. Blisters
Apply cold towels on the areas
affected or take a cold shower.
Apply moisture lotions and not
ointments. Do not break
blisters and try to avoid
repeated sun exposure.
Use sunscreen to avoid a
sunburn.
Seek medical attention for
severe cases
Heatstroke /
Sunstroke
1. High body
temperature
2. Red hot and dry
skin
3. Throbbing
headaches
4. Nausea
5. Unconsciousness
6. Rapid and shallow
breathing
7. Fatigue
Get to a shady cool area.
Sponge or shower with cold
water.
Get a cold towel and rapid it
around the body.
Call the hospital for medical
treatment.
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Temperature & Humidity Combined
Below is a diagram indicating the temperature and humidity level
that you need to be careful of.
70 %
60 %
50 %
40 %
30 %
100°F/ 37.8°C
95°F/ 35°C
90°F/ 32.2°C
85°F/ 29.4°C
80°F/ 26.7°C
Dangerous
Caution
Less
Hazardous
Relative
Humidity
Temperature
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Engineering Controls
General Ventilation
General ventilation can dilute hot air with cooler air (generally
brought in from the outside). This technique clearly works
better in cooler climates than in hot ones. Large areas or
entire buildings identified as high heat areas may require a
permanently installed ventilation system to reduce
temperature levels. In smaller areas, portable or local
exhaust systems may be more effective or practical.
Local Ventilation
Reduce heat stress by increasing the airflow and velocity with
fans and other movers in the work area (as long as the air
temperature is less than the person's skin temperature). If the
air temperature is higher than about 100 to 104F, skin
warming may offset any advantage gained by evaporative
cooling. Because this method does not cool the air, the
increased air flow must contact the worker directly to be
effective. This control will have little, if any, positive effect on
workers wearing vapor-barrier clothing.
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Engineering Controls
Air Treatment / Air Cooling
This control measure differs from ventilation because it cools the air
by removing heat (and sometimes humidity). Air conditioning and air
treatment devices may be expensive to install and operate.
Nonetheless, mechanical refrigeration can be effective in specific
areas such as "cool rooms" (used as recovery areas near hot jobs).
Portable blowers with a built-in air chiller are effective for cooling
asbestos abatement (and similar) enclosures. The main advantages
of blowers are portability and minimal set-up time.
Radiant Heat Reduction
Reflective heat shields and insulation will reduce radiant heat. With
sources of radiation such as heating pipes, it is possible to use both
insulation and surface modifications to achieve a substantial
reduction in radiant heat. If shields are used, it is important to
minimize their influence on the cooling effects of air flow.
Shade
Shade will reduce radiant solar heat and is a widely recognized
control measure. Shading the work area, rest areas, or equipment or
enclosures can significantly decrease the heat load.
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Administrative and Work Practice
Control
Scheduling
If possible, perform potentially hot jobs when heat stress conditions
are at their minimum. Allow latent heat in equipment to dissipate
before work begins. Schedule work for the cooler part of the day,
and schedule routine maintenance and repair work in hot areas for
the cooler seasons of the year.
Fluid Replacement
Place ample supplies of liquids close to the work area. Preferred
drinks are low-sodium, non-carbonated, non-alcoholic, and non-
caffeinated. They should be provided at 50- 60F. Because the
normal thirst mechanism does not ensure sufficient fluid intake,
encourage workers to drink small amounts on a frequent basis, e.g.,
one 4-ounce to 6-ounce cup every 20 minutes. The taste of
commercially available balanced electrolyte replacement drinks
may also encourage fluid intake. (These products are perfectly
acceptable when diluted 50% in water.) Although some
commercial electrolytereplacement drinks contain salt, this is not
necessary for acclimated individuals who generally add enough salt
in their diets.
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Administrative and Work Practice
Control
Acclimation
Most people get used to heat exposure up to a point. This is
called acclimation and it results in less cardiovascular demand for
a given activity. The worker will sweat more efficiently (increasing
evaporative cooling) and may lose less salt, thus will more easily
maintain normal body temperature. Acclimation decreases the
risk of heat-related illnesses and associated unsafe acts.
Deliberate acclimation involves exposing employees to work in a
hot environment for progressively longer periods. For workers
with recent experience (within two weeks) in jobs where heat
levels may produce heat stress, NIOSH recommends the
following regimen: 50% of normal exposure on day one, 60% on
day two, 80% on day three, and 100% percent on day four. For
new workers who will be similarly exposed, the regimen should be
20% on day one, with a 20% increase in exposure each additional
day.
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Administrative and Work Practice
Control
Work/Rest Cycles
Prescribed periods of work and rest are based on specific heat
indices and workload estimates (e.g., ACGIH-TLVs). These
prescribed levels are based on the assumption that the work is
repetitive, controlled, and continuous over an eight-hour shift,
and that the rest area is in an environment similar to that in which
the exposure occurs.
Recovery Times
Recovery may be required for any heat stress exposure.
Recovery is complete when the person's physiological state has
returned to its pre-exposure condition. This means that excess
(stored) body heat has been dissipated, lost fluid has been
replaced, and electrolytes are in balance. To permit dissipation
of stored body heat, the recommended recovery area should be
subjectively cool.
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Administrative and Work Practice
Control
Buddy System
Working in pairs or small teams allows appropriately trained workers to
observe each other for signs of heat-related disorders. Employees
may also share work activities to reduce metabolic heat production.
Personal Monitoring
An individual's physiological response to heat stress can be monitored
with a variety of instruments available on the market. The instruments
measure skin or ear canal temperature as a surrogate for core body
temperature. Some instruments also measure heart and respiration
rates. Unfortunately, there is limited consensus in the scientific
community on how to interpret the results.
Most individuals can be trained to monitor their own heart rate.
Healthy, acclimated workers should avoid prolonged work/environment
combinations that cause their heart rate to exceed the recommended
maximum heart rate, MHR when taken during the first minute of rest.
(MHRs appear in the table below.) The heart rate should drop to 110-
120 beats per minute following the first minute of rest.
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Administrative and Work Practice
Control
Check Times
A prescribed check time (CT) schedule can augment self-
determination. Check times are intervals at which a heat
stress-trained supervisor or observer (including a co-worker or
"buddy") must seek explicit confirmation from individual heat
stress-trained workers that each can continue work. That is,
the observer determines if there are obvious symptoms of heat
disorders, or if there is any sense of diminished capacity. If so,
the exposure is terminated and rest is required. Using CTs
requires each worker, at regular intervals, to explicitly assess
his/her physiological state and ability to continue work, rather
than waiting for symptoms to appear.
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Administrative and Work Practice
Control
Self-Determination
Appropriately trained workers can help monitor their own heat
condition. Training should emphasize that heat stress can affect
an individual's ability to reason clearly. This may cause them to fail
to recognize signs and symptoms of heat stress. For this reason,
self-determination must be augmented by the heat awareness
program, worker training program, and check time and buddy
system controls described in these guidelines.
Other Administrative Controls
Reduce the physical demands of work (such as excessive lifting or
digging) by using powered equipment, increase the number of
workers assigned to a task, use relief workers, and limit worker
occupancy in confined areas.
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Heat Awareness Condition
A "Heat Awareness Condition" is declared when
the potential for heat stress is significant.
The "Condition" is based on the daily weather
forecast of the National Weather Service (NWS) or
other competent forecast. (Use the table below to
compute NWS values.) If extremely hot weather is
predicted for the next day or days, a "Heat
Awareness Condition" is declared to ensure that all
aspects of this procedure are in place, and that
personnel awareness is heightened. Extremely hot
weather is defined here as any of the following:
Ambient temperature in excess of 95 F (=35 C)
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Heat Awareness Condition
NWS apparent temperature (AT), or heat index (HI) in excess
of 90 F (=32 C)
A "Heat Awareness Condition" may exist at many project sites
throughout the summer. During a "Heat Awareness
Condition", the hazards and controls of heat are continuously
emphasized with each employee and supervisor during TSTI.
Workers should be instructed to interrupt heat exposure
before they feel excessive discomfort or symptoms of any
heat-related disorder.
The "Heat Awareness Condition" is based on publicly
available values that makes the program understandable to
most employees. It also makes the program more practical at
projects with limited access to WBGT monitoring equipment.
Some projects advertise a "Heat Awareness Condition" by
posting the predicted heat index at the front gate on a sign in
the shape of a thermometer.
20. DW-HSE-TM035
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Hydrations
The best way to avoid heat strokes and other heat disorders is to keep
your body well hydrated. Drink a lot of water if you are exercising or
working in hot conditions. Doctors usually recommend consuming eight
or more glasses of water per day.
Ventilation
Remain in cool areas where your body can cool itself. If working in hot
conditions, try to take a break to regain energy and to avoid overexposure
to the sun’s rays.
Clothing
What you wear plays a big factor in how your body will handle the heat.
Light clothing and loose fitting clothing will help your body in breathing
and cooling itself naturally. It is fine to wear a hat or cap to shield yourself
from the sun but once you feel warm, remove it. This usually traps the
heat inside your body.
Limit yourself
It is also important to watch the amount of activities you are participating
in during hot days. Don’t overdo it. Heat stroke and other disorders can
take affect in less than an hour. If you feel yourself get warm and
suffocated with the heat, it’s best to take time out and rest in a shady area.
Desert conditions
In desert environments one may not be aware that they are
perspiring due to rapid evaporation.
General Precautions
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Warning!
You need to learn to drink, even when you are not
thirsty.
By the time you feel thirsty you are already 10%
dehydrated
Urine colour gives indication of hydration state ie,
(if urine is dark drink more)
22. DW-HSE-TM035
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The color of Urine tells you how dehydrated you are!
Extremely Dehydrated
Drink Water Immediately
Mildly Dehydrated
Drink More Water
Not Dehydrated
HYDRA CHECK -
NOTE: This is a general guide only and in no way replaces medical advice. Not applicable for person taking
medicine and supplemental vitamins.
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Prevention
Start drinking water
( before you start work),
Drink water
( As much as you need),
Check your Urine colour
(note the urine color),
Ensure adequate ventilation,
Rotate work
( from hot to cool areas),
Report to your Supervisor or the Nurse at first
sign of any problem,
Keep an eye on
your work mates
Remember!
