ADOSH-SF Technical Guideline: Safety in the Heat

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Abu Dhabi Occupational Safety and
Health System Framework
(ADOSH-SF)
ADOSH-SF Technical Guideline
Safety in the Heat
Version 4.0
July 2024

ADOSH-SF – Technical Guideline
Safety in the Heat
Version 4.0 – 15 th July 2024
Page 2 of 24
Table of Contents
1. Introduction ....................................................................................................................................................... 3
2. Assessing Environmental Heat Stress - Thermal Work Limit .......................................................... 3
2.1. Assessment of Environmental Heat Stress and the Thermal Work Limit (TWL) Heat
Stress Index ....................................................................................................................................................... 3
2.2. Determination of TWL ......................................................................................................................... 4
3. Guidelines for Acclimatization and Re-Acclimatization as a Percent of Effort......................... 6
4. Heat Injuries and Illnesses Symptoms and Treatment ...................................................................... 7
4.1. Heat Rash ................................................................................................................................................ 7
4.2. Heat Cramps............................................................................................................................................ 7
4.3. Heat Syncope ......................................................................................................................................... 8
4.4. Heat Exhaustion.................................................................................................................................... 8
4.5. Heat Stroke ............................................................................................................................................. 9
5. Prevention of Heat Illness.......................................................................................................................... 10
5.1. Acclimatization .................................................................................................................................... 10
5.2. Hydration ............................................................................................................................................... 10
5.3. Reduce your risk .................................................................................................................................. 10
5.4. Recommendations for Employers ................................................................................................. 10
5.5. Recommendations for Employees/Employees......................................................................... 11
5.6. Choice of Fluid Replacement Drinks and Electrolytes ........................................................... 11
6. Document Amendment Record ............................................................................................................... 12
Appendix 1: Example of Educational Messages for Employees .......................................................... 13
Appendix 2: Example Urine Charts to aid Employees to Self-Assess Hydration Levels ............. 14
Appendix 3: Example - Dehydration and Heat Illness Protocol ........................................................... 17
Appendix 4: Hydration Testing (Conducted by Nurse or Medical Officer) ....................................... 18
Appendix 5: Example Dehydration Test Report ........................................................................................ 21
Appendix 6: Example Working in Heat Inspection Checklist ................................................................. 22
Appendix 7: Example Flag System for Communicating Heat Condition ........................................... 23

ADOSH-SF – Technical Guideline
Safety in the Heat
Version 4.0 – 15 th July 2024
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1. Introduction
(a) The following guidance document provides information to employers in the Emirate
of Abu Dhabi that have employees working in high temperature environments. High
temperature environments includes both weather (working outdoors or open to the
outdoors in hot conditions) and hot site operations (furnaces, ovens, other high
temperature operations). This document is designed to incorporate requirements set
at Emirate and Federal level. If guidance provided in this document conflict with
requirements set by a relevant authority, employers must follow the regulatory
requirement.
2. Assessing Environmental Heat Stress - Thermal Work Limit
(a) As per the requirements of Clause
3.2(b)(ii) of ADOSH-SF - CoP 11.0 – Safety in the
Heat, employers shall develop a process for assessing conditions to determine what
control requirements are required for the level of risk in the particular work
environment and to calculate correct work/rest breaks and fluid (rehydration)
consumption rates.
2.1. Assessment of Environmental Heat Stress and the Thermal Work Limit (TWL) Heat Stress
Index
(a) The Thermal Work Limit (TWL), which has been validated for Gulf conditions, is the
heat stress index that has been researched and adopted by within the Emirate of Abu
Dhabi to enable safe management of work in heat. It gives a measure of the maximum
safe work rate for the conditions. If TWL is too low then even low rates of work cannot
safely be carried out continuously.
(b) TWL, measured in watts per square meter (W/m 2 ), is the maximum rate at which heat
can be lost to the environment in the conditions. TWL is calculated from environmental
parameters assuming that employees are well hydrated and acclimatized to the
conditions and are self-paced.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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2.2. Determination of TWL
(a) To determine TWL the following must be measured:
Dry Bulb Temperature (ambient air temperature) in degrees °C
Wet Bulb Temperature (determined by the
humidity/evaporation) in degrees °C
Globe Temperature (determined by the radiant heat) in degrees °C
Wind speed in meters per second
(b) Instruments are available that carry out all of these measurements and internally
compute the TWL.
(c) Alternative single instruments measuring Dry Bulb (air temperature), Globe
Temperature (radiant heat), Wet Bulb (evaporative cooling) and Air Velocity (wind
speed) can be used and individual readings entered into the online Thermal Work Limit
calculator available at: to calculate the overall TWL heat stress index result and
working zone.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Table 1 – Thermal Work Limit Zones and Interventions for Management of Work

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Safety in the Heat
Version 4.0 – 15 th July 2024
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3. Guidelines for Acclimatization and Re-Acclimatization as a Percent of Effort
(a) As per the requirements of Section 3.2(b)(i) of
ADOSH-SF - CoP 11.0 – Safety in the
Heat, employers will develop a process for acclimatizing employees to high
temperature work environments. This section provides guidance on how to
acclimatize employees.
Acclimatization Guidelines
Activity (percent of full work assignment)
Day Experienced Employee New Employee
1 50% 20%
2 60% 40%
3 80% 60%
4 100% 80%
5 100% 100%
Re-Acclimatization Guidelines
Days Away from Heat-Related Job Routine Exposure Sequence
(percent of full work assignment)
Absence Illness 1st 2nd 3rd 4th
< 4 — 100%
4 - 5 1 - 3 R/E* 100%
6 - 12 4 - 5 80% 100%
12 - 20 6 - 8 60% 80% 100%
> 20 > 8 50% 60% 80% 100%
*R/E – Reduced expectations
Table used courtesy of the National Safety Council, Itasca, IL

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Safety in the Heat
Version 4.0 – 15 th July 2024
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4. Heat Injuries and Illnesses Symptoms and Treatment
(a) As per the training and competency requirements of Section 2.0 of
ADOSH-SF - CoP
11.0 – Safety in the Heat, employers shall ensure employees, supervisors, and first
aiders know the signs and symptoms of heat related injuries and illnesses. This
section provides guidance on the signs, symptoms and treatment of heat related
injuries and illnesses.
(b) Heat injuries and illnesses results when the body cannot effectively get rid of heat as
fast as it is generated. If not recognized and treated early this can lead to serious
illness even death.
4.1. Heat Rash
(a) Heat rash is a skin irritation caused by excessive sweating during hot, humid weather.
The symptoms include:
(i) Heat rash looks like a red cluster of pimples or small blisters; and
(ii) It is more likely to occur on the neck and upper chest, in the groin, under the
breasts, and in elbow creases.
(b) First Aid for employees experiencing heat rash should include:
(i) Should try to work in a cooler, less humid environment when possible;
(ii) Should keep the affected area dry; and
(iii) May use dusting powder to increase comfort.
4.2. Heat Cramps
(a) Heat cramps usually affect employees who sweat a lot during strenuous activity. This
sweating depletes the body's salt and moisture levels. Low salt levels in muscles
causes painful cramps. Heat cramps may also be a symptom of heat exhaustion.
(b) The symptoms for heat cramps includes:
(i) Muscle pain or spasms usually in the abdomen, arms, or legs.
(c) First Aid for employees with heat cramps should include:
(i) Stop all activity, and sit in a cool place;
(ii) Drink clear juice or a sports beverage;
(iii) Do not return to strenuous work for a few hours after the cramps subside
because further exertion may lead to heat exhaustion or heat stroke; and
(iv) Seek medical attention if any of the following apply:
1. The employee has heart problems;
2. The employee is on a low-sodium diet; and
3. The cramps do not subside within one hour.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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4.3. Heat Syncope
(a) Heat syncope is a fainting (syncope) episode or dizziness that usually occurs with
prolonged standing or sudden rising from a sitting or lying position. Factors that may
contribute to heat syncope include dehydration and lack of acclimatization.
(b) The symptoms for heat syncope include:
(i) Light-headedness;
(ii) Dizziness; and
(iii) Fainting.
(c) First Aid for employees with heat syncope should include:
(i) Sit or lie down in a cool place when they begin to feel symptoms; and
(ii) Slowly drink water, clear juice, or a sports beverage.
4.4. Heat Exhaustion
(a) Heat exhaustion is the body's response to an excessive loss of the water and salt,
usually through excessive sweating. Employees most prone to heat exhaustion are
those that are elderly, have high blood pressure, and those working in a hot
environment.
(b) Symptoms of heat exhaustion include:
(i) Heavy sweating;
(ii) Extreme weakness or fatigue;
(iii) Dizziness, confusion;
(iv) Nausea;
(v) Clammy, moist skin;
(vi) Pale or flushed complexion;
(vii) Muscle cramps;
(viii) Slightly elevated body temperature; and
(ix) Fast and shallow breathing.
(c) First Aid, treat an employee suffering from heat exhaustion with the following:
(i) Have them rest in a cool, shaded or air-conditioned area;
(ii) Have them drink plenty of water or other cool, nonalcoholic beverages; and
(iii) Have them take a cool shower, bath, or sponge bath.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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4.5. Heat Stroke
(a) Heat stroke is the most serious heat-related disorder. It occurs when the body
becomes unable to control its temperature: the body's temperature rises rapidly, the
sweating mechanism fails, and the body is unable to cool down. When heat stroke
occurs, the body temperature can rise to 106 degrees Fahrenheit or higher within 10
to 15 minutes. Heat stroke can cause death or permanent disability if emergency
treatment is not given.
(b) Symptoms of heat stroke include:
(i) Hot, dry skin or profuse sweating;
(ii) Hallucinations;
(iii) Chills;
(iv) Throbbing headache;
(v) High body temperature;
(vi) Confusion/dizziness; and
(vii) Slurred speech.
(c) First Aid, take the following steps to treat an employee with heat stroke:
(i) Call emergency contact number and notify supervisor;
(ii) Move the sick employee to a cool shaded area;
(iii) Cool the employee using methods such as:
1. Soaking their clothes with water;
2. Spraying, sponging, or showering them with water; and
3. Fanning their body.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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5. Prevention of Heat Illness
5.1. Acclimatization
(a) People accustomed to working in the heat have adapted to cope better with the
conditions. It takes over two weeks to become fully acclimatized; however adaptation
is rapid in the first few days.
5.2. Hydration
(a) Keeping well hydrated is one of the most effective ways to reduce the risk of heat
illness, it is essential you drink before starting work and at frequent intervals during
the day, as a guideline you should be drinking 4-6 liters of water per day while in the
Gulf region (2 liters every 2-3 hours).
5.3. Reduce your risk
(a) Limit your heat exposure for new arrivals from overseas or the first days if you are
returning after being out of a “heat zone”, refer to Section 3; and
(b) Drink regularly, even if you don’t feel thirsty. Water is the best; avoid caffeine
containing drinks like coffee, cola and especially energy drinks.
5.4. Recommendations for Employers
(a) Employers should take the following steps to protect employees from heat stress:
(i) Schedule maintenance and repair jobs in hot areas for cooler months;
(ii) Schedule hot jobs for the cooler part of the day;
(iii) Acclimatize employees by exposing them for progressively longer periods to hot
work environments;
(iv) Reduce the physical demands of employees;
(v) Use relief employees or assign extra employees for physically demanding jobs;
(vi) Provide cool water or liquids to employees:
1. Avoid drinks with caffeine, alcohol, or large amounts of sugar.
(vii) Provide rest periods with water breaks;
(viii) Provide cool areas for use during break periods;
(ix) Monitor employees who are at risk of heat stress;
(x) Provide heat stress training that includes information about:
1. Employee risk;
2. Prevention;
3. Symptoms;
4. The importance of monitoring oneself and co-workers for symptoms;
5. Treatment; and
6. Personal protective equipment.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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5.5. Recommendations for Employees/Employees
(a) Employees should avoid exposure to extreme heat, sun exposure, and high humidity
when possible. When these exposures cannot be avoided, employees should take the
following steps to prevent heat stress:
(i) Wear light-colored, loose-fitting, breathable clothing such as cotton:
1. Avoid non-breathing synthetic clothing.
(ii) Gradually build up to heavy work;
(iii) Schedule heavy work during the coolest parts of day;
(iv) Take more breaks in extreme heat and humidity:
1. Take breaks in the shade or a cool area when possible.
(v) Drink water frequently. Drink enough water that you never become thirsty;
(vi) Avoid drinks with caffeine, alcohol, and large amounts of sugar;
(vii) Be aware that protective clothing or personal protective equipment may
increase the risk of heat stress; and
(viii) Monitor your physical condition and that of your co-workers.
5.6. Choice of Fluid Replacement Drinks and Electrolytes
(a) The fluid intake required to maintain hydration is determined by the sweat rate which
in turn is determined by the work rate and the conditions. Sweat rates vary
considerably and increase with acclimatization. The following recommendations are
for the average acclimatized employee. Replacement of the fluid lost in sweat requires
intake of adequate quantities of water and salt. Drinking at mealtimes replaces both
and is essential.
(b) Remember to encourage employees to:
(i) add a little extra salt to their meals during hot weather, salt tablets are not
permitted;
(ii) drink water with meals;
(iii) limit consumption of soft drinks as the sugar content is high; and
(iv) limit consumption of caffeinated drinks (coffee, tea, cola) and ‘energy drinks’, as
the caffeine may reduce fluid retention.
(c) If employees are sweating heavily between meals, an electrolyte replacement drink is
recommended. Replacing salt as it is lost helps the body absorb and retain the water
consumed:
(i) sports drinks are high in sugar and often quite acidic which can damage teeth.
They are not designed for prolonged consumption at work;
(ii) for prolonged consumption, a fluid with 4% or less sugar is recommended;
(iii) appropriate products designed for industrial use are available commercially;
(iv) the suggested schedule is to drink the electrolyte replacement fluid at every
second drink (i.e. one for one with water); and
(v) for diabetics or those on sugar restricted diets, medical advice is required on the
preferred fluids for rehydration.

ADOSH-SF – Technical Guideline
Safety in the Heat
Version 4.0 – 15 th July 2024
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6. Document Amendment Record
Version Revision Date Description of Amendment Page/s Affected
4.0 15th July 2024
System acronym updated from OSHAD-
SF to ADOSH-SF to accurately reflect
document title
Throughout
Change from OSHAD to ADPHC
Change of Logo
Minor editorial changes throughout the
document without changing requirements.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 1: Example of Educational Messages for Employees
As per the requirements of Section 2(b)(v) of ADOSH-SF - CoP 11.0 – Safety in the Heat,
employers will provide informational and awareness campaigns to raise awareness and
maintain awareness amongst the workforce. The following is an example of information that
should be provided to employees:
“Working in extreme heat without proper controls can be fatal! Look out for yourself and your
friends at work.”
SUMMER IN THE UAE IS VERY EXTREME AND CAN LEAD TO DEATH FROM HEAT RELATED
ILLNESS.
THE KEY POINTS TO REMEMBER ARE:
1. Drink at least 2 litres of water every 2-3 hours;
2. Add a little more salt to meals in summer to replace salt lost in sweat;
3. Slow down and rest in very hot weather conditions;
4. Get plenty of sleep and rest at night; and
5. When you feel unwell tell your supervisor or the work clinic if you have one.
Recommendations for employees:
1. Read, understand and follow the employer’s occupational health and safety procedures
and instructions regarding work in hot environments;
2. Report all signs of heat illness to the supervisor (feeling faint, dizziness, fatigue,
headache, nausea, vomiting, and cramps);
3. Drink enough water during the day and maintain proper hydration:
• Come to work fully hydrated (drink plenty of water before you get to work);
• Drink plenty of water during the shift at least 2 liters every 2-3 hours in summer
(or rehydration fluid approved by the employer);
• Drink water regularly and make it a way of life; and
• If you drink water only when you are thirsty it is too late-drink even when you are
not thirsty in the heat.
• Wear appropriate clothing (lightweight, light-colored, loose-fitting, cotton) and
carry a water container with you of at least 1-2 liters to fill regularly;
• Self-pace your work – do not push your body beyond its limits;
• Report non-acclimatization to supervisor (if you have been away from work for
more than 14 days) and try to acclimatize for 5-7 days before starting hard work
in a hot environment; and
• Look out for signs of heat illness in the people you work with and take them to a
shady area and cool them down – call for help.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 2: Example Urine Charts to aid Employees to Self-Assess Hydration Levels
As per the requirements of Section 3.2(h) of ADOSH-SF- CoP 11.0 – Safety in the Heat,
employers will post urine charts, informational fliers on heat stress, or other similar methods
to help employees identify if they are becoming dehydrated. The following diagrams are
examples of urine charts that can be posted in toilet facilities to help employees determine if
they are drinking enough fluids to prevent a heat related injury or illness.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Safety in the Heat
Version 4.0 – 15 th July 2024
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Extremely Dehydrated
Drink Water Immediately
Mildly Dehydrated
Drink More Water
Not Dehydrated

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 3: Example - Dehydration and Heat Illness Protocol
The on-site protocol and preparation for emergencies involving heat related illness and
dehydration cases should be planned before heat exposure occurs and be part of the heat
stress management process and understood by all personnel. Below is an example protocol
that can be used onsite to plan what should be done to manage cases if they occur at the
worksite. This can be modified for a particular worksite accordingly.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 4: Hydration Testing (Conducted by Nurse or Medical Officer)
Hydration level is reflected in the specific gravity (SG) of the urine, a measure of its
concentration. This can be used as a monitoring and educational tool to encourage employees
to drink more fluids during the work shift and avoid heat related illness associated with
dehydration. Testing must be carried out by suitably trained personnel (e.g. Nurse or Medical
Officer).
1. Medical gloves must be worn when handling urine; and
2. A fresh midstream urine specimen is required.
Safety Limits
At the start of the shift Not more than 1.015
Other times e.g. end of shift Not more than 1.029
When to Test Hydration Levels
1. Anyone who reports sick or with an injury should be tested for hydration levels; and
2. Un-acclimatised employees returning or coming from a cooler climate.
Communication
1. Record the result and actions recommended on the Dehydration Test Report form (see
Appendix 1); and
2. File the form and if required advise the supervisor of the result
Follow the actions prescribed in the table ‘Action levels according to urine specific gravity.
Failed Tests
If an employee fails a hydration test, DO NOT let them proceed to work station, ensure they
drink water. Re-test after one hour and continue until correctly hydrated (SG<1.015).
In Case of Any Heat Illness Symptoms refer the person to the medical centre.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Action Levels According to Urine Specific Gravity (SG)
SG Level Specific Gravity Meaning Action
Normal
1.000
to
1.015
Hydration
adequate
• Fluid intake is adequate to
maintain desired hydration
status
• Maintain fluid intake
Alert
1.016
to
1.020
Slightly
dehydrated
• Extra fluids required
• Rehydrate before starting the
work
1.021
to
1.029
Moderately
dehydrated
• Extra fluids required
• Rehydrate before starting the
work and every 15 to 20
minutes during the shift
Action 1.030+ Significantly
dehydrated
• Extra fluids required
• Rehydrate before starting the
work and every 15 to 20
minutes during the shift
• Investigate cause of
dehydration
• Remove employee from hot
workplace
• Employee not to be allowed
to perform this work until
hydration levels improved
• Recheck SG in 4 hours
Procedure (Digital Refractometer)
1. Check the instrument calibration daily, using distilled or de-ionised water.
2. Turn the instrument on.
3. Place a few drops of water on the glass plate (this should be covered evenly with no
bubbles).
4. Press the zero button. The reading will be set at 1.000.
5. Place a few drops of urine on the glass plate using a disposable dropper pipette.
6. Press the start button.
7. Wipe the surface of the plate gently clean by using a tissue dampened with water.
8. Advise the person of any actions required (see action levels above).
9. Dispose of the urine into the toilet. Wash hands thoroughly.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Procedure (Optical Refractometer)
1. Check the instrument calibration daily, using distilled or de-ionized water (steps 3-5
below), this should give a specific gravity (SG) reading of 1.000. Re-calibrate if necessary
according to manufacturer’s instructions.
2. Place two drops of urine on the face of the prism of the refractometer using a disposable
dropper pipette.
3. Close the daylight plate gently. The sample must spread over the prism surface – free of
any bubbles.
4. Hold the instrument up to the eye and look into the light. Focus if necessary, using the
eyepiece focusing ring. The SG is read on the left hand scale where the blue line
intersects the scale.
5. Wipe the surface of the prism and daylight plate gently clean, by using a tissue
dampened with water.
6. Advise the person of any actions required (see action levels above).
7. Dispose of the urine into the toilet. Wash hands thoroughly.
8. Use the color urine chart to educate employees to assess the color of their urine for
hydration and place the charts in restrooms and ablution facilities as a reminder to drink
enough.

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 5: Example Dehydration Test Report
Name Employee Number:
Signature Date
Reason for Test
New Employee Y N
Returning from Leave Y N
Work in
Withdrawal
Zone
Before Y N
After Y N
Developed symptoms Y N
Voluntary Y N
Dehydration Test
Result
Action Level
Normal Alert Action (moderate) Action (severe)
Recommendations
Maintain Fluid Intake
Increase Fluid Intake
Rehydrate Before Work
Additional
Re-check Required N Y Time:
Result reported N Y To:
Name of Testing Officer
Signature

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 6: Example Working in Heat Inspection Checklist
A working in heat inspection checklist can be used to identify the requirements of a worksite
heat stress management program and complete an audit of various elements to be considered
and made available. Below is an example of a checklist that can be modified to suit the
particular worksite and expected or measured environmental conditions onsite.
Inspection of Worksite
Yes No
1. Does the worksite have rest areas and shade?
2. Are there poster reminding employees (employees) to drink water?
3. Is there a communication system for informing employees (employees) of
the current environmental conditions? (e.g., flag system)
4. Is there cool fresh water (or other fluids) available
5. If cooler is used to supply water, is the lid sealed with tape and the date of
filled written on the container?
6. Are snacks/fruit available for employees (employees) during the workday
to ensure they maintain a nutrient and caloric intake needed for working in
the heat?
7. Are there posters reminding employees (employees) of the signs and
symptoms of heat injuries and illnesses?
8. Are first aiders available on site?
9. Are contact phone numbers available for medical emergencies?
Training / Education
Yes No
1. Do employees know the signs and symptoms of heat injuries/illnesses
2. Is there a first aid trained provider onsite (response within 3 minutes)?
3. Does the first aid provider have a training certificate that is current and
issued by a valid training provider?
4. Does the first aid provider know how to treat for heat injuries and
illnesses?
5. Does the first aid provider have a medical kit that is complete and stocked
for the hazards of the worksite?
6. Is there a way for the worksite to call for emergency medical services?
7. Does the supervisor or first aid provider know how to call for emergency
medical services and direct them to the site?
8. Has the worksite had drills where the scenario is a heat related injury or
illness?
Site Procedures
Yes No
1. Does the site have a process for evaluating the environmental conditions
and heat stress?
2. Are meals provided by the employer?
o If yes, are they sufficient and well balanced for employees working in high
temperature environments?
3. Was there a pre-work briefing to remind employees of the hazards of
working in the heat and ways to prevent heat related injuries and
illnesses?
4. Is the site following the Ministry of Labour’s Mid-Day Break for employees
(employees) that work outside in the summer months?

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Safety in the Heat
Version 4.0 – 15 th July 2024
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Appendix 7: Example Flag System for Communicating Heat Condition
The following is an example of a flag system that can be used on large worksite as a visual
communication means to inform employees of the TWL and actions to take to prevent heat
related injuries and illnesses.
Flag poles shall be high enough that they can be seen above any surrounding structure. It may
be necessary to post multiple flagpoles around large worksites (e.g., constructions sites) to
ensure employees can see them from their work location. When multiple contractors are
located at a worksite, it is important that the Principle Contractor and/or site owner coordinate
to ensure all flags are changed as needed to reflect the current worksite conditions.
Signs should also be posted around the sites and at any rest/shade shelter to remind
employees what actions should be taken to prevent heat related injuries and illness depending
on the color of the flag that is raised.