Heat Stress - Heat Related Illness

Types of Heat-related Illnesses Heat Stroke

Heat stroke is the most serious heat-related illness. 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°F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency treatment is not given.

Symptoms of heat stroke include:

• Confusion, altered mental status, slurred speech • Loss of consciousness (coma) • Hot, dry skin or profuse sweating • Seizures • Very high body temperature • Fatal if treatment delayed

First Aid Take the following steps to treat a worker with heat stroke:

• Call 911 for emergency medical care. • Stay with worker until emergency medical services arrive. • Move the worker to a shaded, cool area and remove outer clothing. • Cool the worker quickly with a cold water or ice bath if possible; wet the skin, place cold wet cloths on skin, or soak clothing with cool water. • Circulate the air around the worker to speed cooling. • Place cold wet cloths or ice on head, neck, armpits, and groin; or soak the clothing with cool water.

Heat Exhaustion

Heat exhaustion is the body’s response to an excessive loss of the water and salt, usually through excessive sweating. Workers most prone to heat exhaustion are those that are elderly, have high blood pressure, and those working in a hot environment.

Symptoms of heat exhaustion include:

• Headache • Nausea • Dizziness • Weakness • Irritability • Thirst • Heavy sweating • Elevated body temperature • Decreased urine output

First Aid Treat a worker suffering from heat exhaustion with the following:

• Take worker to a clinic or emergency room for medical evaluation and treatment. • If medical care is unavailable, call 911. • Someone should stay with worker until help arrives. • Remove worker from hot area and give liquids to drink. • Remove unnecessary clothing, including shoes and socks. • Cool the worker with cold compresses or have the worker wash head, face, and neck with cold water. • Encourage frequent sips of cool water.

Rhabdomyolysis

Rhabdomyolysis is a medical condition associated with heat stress and prolonged physical exertion, resulting in the rapid breakdown, rupture, and death of muscle. When muscle tissue dies, electrolytes and large proteins are released into the bloodstream that can cause irregular heart rhythms and seizures, and damage the kidneys.

Symptoms of rhabdomyolysis include:

• Muscle cramps/pain • Abnormally dark (tea or cola colored) urine • Weakness • Exercise intolerance • Asymptomatic

First Aid Workers with symptoms of rhabdomyolysis should:

• Stop activity. • Increase oral hydration (water preferred). • Seek immediate care at the nearest medical facility. • Ask to be checked for rhabdomyolysis (i.e., blood sample analyzed for creatine kinase).

Heat Syncope

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.

Symptoms Symptoms of heat syncope include:

• Fainting (short duration) • Dizziness • Light-headedness during prolonged standing or suddenly rising from a sitting or lying position

First Aid Workers with heat syncope should:

• Sit or lie down in a cool place. • Slowly drink water, clear juice, or a sports drink. Heat Cramps

Heat cramps usually affect workers 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.

Symptoms

• Muscle cramps, pain, or spasms in the abdomen, arms, or legs

First Aid Workers with heat cramps should:

• Drink water and have a snack and/or carbohydrate-electrolyte replacement liquid (e.g., sports drinks) every 15 to 20 minutes. • Avoid salt tablets. • Get medical help if the worker has heart problems, is on a low sodium diet, or if cramps do not subside within 1 hour.

Heat Rash

Heat rash is a skin irritation caused by excessive sweating during hot, humid weather.

Symptoms Symptoms of heat rash include:

• Looks like red cluster of pimples or small blisters • Usually appears on the neck, upper chest, groin, under the breasts, and in elbow creases

First Aid Workers experiencing heat rash should:

• When possible, a cooler, less humid work environment is best treatment. • Keep rash area dry. • Powder may be applied to increase comfort. • Ointments and creams should not be used.

Control of Heat Stress

Employers should reduce workplace heat stress by implementing engineering and work practice controls.

Engineering controls might include those that:

• Increase air velocity. • Use reflective or heat-absorbing shielding or barriers. • Reduce steam leaks, wet floors, or humidity.

Work practice recommendations include the following:

• Limit time in the heat and/or increase recovery time spent in a cool environment. • Reduce the metabolic demands of the job. • Use special tools (i.e., tools intended to minimize manual strain). • Increase the number of workers per task. • Train supervisors and workers about heat stress. • Implement a buddy system where workers observe each other for signs of heat intolerance. • Require workers to conduct self-monitoring and create a work group (i.e., workers, a qualified healthcare provider, and a safety manager) to make decisions on self-monitoring options and standard operating procedures. • Provide adequate amounts of cool, potable water near the work area and encourage workers to drink frequently. • Implement a heat alert program whenever the weather service forecasts that a heat wave is likely to occur. • Institute a heat acclimatization plan and increase physical fitness. Training

Train workers before hot outdoor work begins. Tailor training to cover worksite- specific conditions.

Employers should provide a heat stress training program for all workers and supervisors about the following:

• Recognition of the signs and symptoms of heat-related illnesses and administration of first aid. • Causes of heat-related illnesses and the procedures that will minimize the risk, such as drinking enough water and monitoring the color and amount of urine output. • Proper care and use of heat-protective clothing and equipment and the added heat load caused by exertion, clothing, and personal protective equipment. • Effects of nonoccupational factors (drugs, alcohol, obesity, etc.) on tolerance to occupational heat stress. • The importance of acclimatization. • The importance of immediately reporting to the supervisor any symptoms or signs of heat-related illness in themselves or in coworkers. • Procedures for responding to symptoms of possible heat-related illness and for contacting emergency medical services.

In addition, supervisors should be trained on the following:

• How to implement appropriate acclimatization. • What procedures to follow when a worker has symptoms consistent with heat-related illness, including emergency response procedures. • How to monitor weather reports. • How to respond to hot weather advisories. • How to monitor and encourage adequate fluid intake and rest breaks. Acclimatization

Acclimatization is the result of beneficial physiological adaptations (e.g., increased sweating efficiency, etc.) that occur after gradual increased exposure to a hot environment. Employers should ensure that workers are acclimatized before they work in a hot environment.

• Gradually increase workers’ time in hot conditions over 7 to 14 days. • For new workers: o The schedule should be no more than 20% of the usual duration of work in the heat on day 1 and no more than 20% increase on each additional day. • For workers with previous experience: o The schedule should be no more than 50% of the usual duration of work in the heat on day 1, 60% on day 2, 80% on day 3, and 100% on day 4. • Closely supervise new employees for the first 14 days or until they are fully acclimatized. • Non-physically fit workers require more time to fully acclimatize. • Acclimatization can be maintained for a few days of non-heat exposure. • Taking breaks in air conditioning will not affect acclimatization. Hydration

Employers should provide the means for appropriate hydration of workers.

• Water should be potable, <15°C (59°F), and made accessible near the work area. • Estimate how much water will be needed and decide who will obtain and check on water supplies. • Individual, not communal, drinking cups should be provided. • Encourage workers to hydrate themselves.

Workers should drink an appropriate amount to stay hydrated.

• If in the heat <2 hours and involved in moderate work activities, drink 1 cup (8 oz.) of water every 15–20 minutes. • During prolonged sweating lasting several hours, drink sports drinks containing balanced electrolytes. • Avoid alcohol and drinks with high caffeine or sugar. • Generally, fluid intake should not exceed 6 cups per hour. Rest Breaks

Employers should ensure and encourage workers to take appropriate rest breaks to cool down and hydrate.

• Permit rest and water breaks when a worker feels heat discomfort. • Modify work/rest periods to give the body a chance to get rid of excess heat. • Assign new and unacclimatized workers lighter work and longer, more frequent rest periods. • Shorten work periods and increase rest periods: o As temperature, humidity, and sunshine increase. o When there is no air movement. o If protective clothing or equipment is worn. o For heavier work.

Take breaks Start early if possible, especially on attic jobs Drink plenty of water, we provide coolers and ice Avoid caffeine and alcohol Use fans in attics, we provide these If working on a roof for extended amount of time use sunshades (awnings) we provide these Wear a hat Use Sunscreen Loose fitting clothes. Wear sunglasses