The information contained in this page was extracted from MSHA Safety Manual Number 6. For the purpose of providing you with a document better suited for presentation on the internet we have excluded some of the graphics found in the manual.

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PREFACE

   Historically, the engineer has made mining possible for human beings. Today the proper object is to provide conditions in which the miner is a contented individual operating at maximum efficiency.

P.R. Davis and A. A. Knight
Ergonomics of Mining, Medicine in the Mining Industries
J. M. Rogan, ed., F. A. Davis Company, 1972

  This is one of a series of manuals prepared by the technical staff of the Mine Safety and Health Administration (MSHA) to acquaint the reader with a specific area of mining. This manual deals with the nature of heat stress and strain and the mechanism of heat control in the human body. The signs of heat-related physiological disorders and the first aid for heat stress victims are described, and the stress control measures in mines are noted.

   This is a revised version of a manual originally published under the same title in 1976. Since then, no new heat stress studies have been made in mining.

   A list of references (Bibliography) is also included for those interested in additional information on the topics discussed in this pamphlet.

INTRODUCTION
There is the right of every red-blooded man to be assured that his work will be a daily satisfaction to himself; that it is a work which is contributing to the welfare and advance of his country; and that it will build for him a position of dignity and consequence among his fellows.

Herbert C. Hoover,
Principles of Mining ,
McGraw-Hill Book Co., Inc. 1909

  Enforcement is a good principle which can only be effective when accompanied with a good education and training effort, an effort to educate the miners in the health hazards, an effort to train miners on the importance of maintaining a healthy environment, an effort to motivate the miners to know and play a major role to improve the environment in mines.

Robert E. Barrett, Administrator,
Mining Enforcement and Safety Administration,
Annual Meeting of the American Public Health
Association, 1976

 

   Deep mines and mines sunk in hot countries are hot work sites. Some underground mines in moderate geographic zones are hot because of the unusually high heat flow from the earth. Many mines in the southwestern United States are located along a high heat zone. The thrust for the development of new sources of minerals calls for an expansion of underground mining in deeper, and therefore, hotter levels of the earth crust.

   In mining, as in other industries, the exposure of workers to very hot conditions is unhealthy and unproductive. Persons working in hot, humid work sites tend to be inefficient; quite often workers prefer to stay away from work or ignore unsafe working situations. Studies in South African gold mines have shown that high temperatures reduce the work output of miners.

   Dexterity and coordination, ability to observe irregular, faint optical signs, ability to remain alert during lengthy and monotonous tasks, and the ability to make quick decisions are adversely affected by the heat strain. For example, in a 3hour drilling operation performed under varying room temperatures, the best results were obtained at 84º F; the performance was reduced to 75 percent capacity at a room temperature of 91º F, to 50 percent at 96, and to 25 percent at 99º F. For a new employee., 77º F room temperature is the upper limit for best performance. Heat strain can also show itself in the form of irritation, anger, and other emotions leading to rash acts by persons performing hazardous jobs. The lowest accident rates have been related to men working at temperatures below 70º F, the highest to temperatures of 80º F and over.

   There is some evidence that older persons have a lower tolerance for heat. They start to sweat later than do younger individuals. It takes longer for body temperature to return to normal levels in older individuals exposed to heat stress. In one study the majority of all the individuals who fell victim to heatstroke were over 60 years of age.

    Warm-blooded animals can function regularly in almost all types of weather and climate because they can maintain their body temperature within a narrow range. Carbohydrates, fats and proteins in our food provide energy for our daily activities. The human body, like mechanical devices and machines, is not 100 percent efficient. At best, only 25 percent of the energy generated by the body’s metabolism is converted into mechanical work. Thus, at least 75 percent of the energy produced by metabolism is converted into heat which is needed to support the metabolic process. However, too much heat will interfere with the metabolism and cause health problems such as heatstroke, fainting, exhaustion, cramps and water deficiency.

The human body may be thought of as having a core and a shell; this assumption will make it easier to understand the heat control in the body. The core contains the deep muscles and tissues, including the heart, lungs, abdominal organs, and brain. The shell contains the skin, tissues forming the skin base, and the muscles close to the skin; the hands and feet are also part of the body shell.

    Rectal temperatures are a measure of the core temperature. At rest, the body core temperature remains almost uniform. Under extreme conditions-from sleeping in a cold environment to doing hard work in a hot work site — the core temperature varies from 95 to 104ºF.

    The health of a person at work and at rest depends upon the stability of the core body temperature. The core cannot store an excessive amount of heat without upsetting its delicate temperature balance. oral temperatures are a measure of core and the shell temperatures; the body core can dissipate its heat only through the shell. Blood serves as an effective vehicle for heat transfer between the body core and the shell.

   

Dissipation of Heat From Human Body

Two or more bodies having different temperatures can exchange their heat in several ways:

 

• convection is a mechanism of heat exchange through a medium such as air or water
• conduction is the transfer of heat between two bodies in contact
• radiation is a heat loss due to the emission of heat rays from hotter to cooler surfaces

  Conduction is not a direct route of heat loss to the environment for the human body — most of the body is in contact with the clothing. Heat rays (radiation) do not need a medium like air or water for their transfer. Thus, hot walls in a mine will not only warm the mine air through convection, but also will emit heat directly through radiation and affect persons working in the area.

    Muscular work can increase the heat production in the body 10 to 20 times that at rest. The excess heat generated in the body is dissipated through convection, radiation and evaporation. When the body is at rest, the combination of convection and radiation accounts for about threefourths of the dissipated body heat; and the remaining one-fourth is lost through evaporation. Heat loss through evaporation can take place in the following ways:

• sweat evaporation through almost two million sweat glands in the skin
• saturation of the inhaled air in the lungs with water vapor
• invisible loss of water through the skin without involvement of the sweat glands

   Any increase in physical activity calls for more intense evaporation from the skin because heat losses from the lungs and through convection and radiation are not enough to keep the body temperature steady. 
   

    The human body, when exposed to a wide range of increasing heat loads, can mobilize its resources and restore a balance between heat gain and heat loss. This leads to a new steady core temperature at a somewhat higher level. Heat stress refers to the total heat-related load on the individual from both environmental and metabolic sources.

    An increasing environmental heat stress causes changes in sweat rate, heartbeat rate, and body core temperature of the affected individual.

    Heat strain refers to the adjustments made by the individual in response to the heat stress. These adjustments include biochemical, physiological, and psychological processes.

    Healthy and physically fit persons are able to work under heat strain as long as sweat evaporation takes place; by contrast, persons with health problems have a limited capacity for heat strain endurance.

    An increase in the sweat rate is the first sign of the heat strain. The steady rise of the sweat rate causes an excessive wetting of the skin. Extended exposure to heat will cause a decline in sweat rate. The sweat gland fatigue and consequent reduction in sweat production indicates a very high level of heat strain.

    Some people have no sweat glands at all; such a condition should disqualify them from working in hot environments.

    Individuals working in hot areas under emergency conditions (mine rescue workers) and highly motivated individuals working in nonemergency conditions may overstrain themselves. To prevent this kind of strain, the workloads may be reduced, more recovery time may be allowed, or cool rest areas may be provided.
   

What Constitutes a “Hot” Work Site

    High or moderately high levels of work produce a great deal of heat in the body. Moreover, the following factors add to the discomfort of a hot work site:

 

• high air temperatures
• high surface temperatures
• high atmospheric humidity
• relatively low air movement

Here is one definition of hot working place:

Hot work site means any combination of air temperature, humidity, radiation and. wind speed that exceeds a wet bulb globe temperature of 79º F.

   The wet bulb globe temperature is measured with the help of a cluster of thermometers adapted to measure various work .site temperatures:

• dry bulb thermometer is used to measure the temperature of mine air to get an estimate of convective heat exchange in the mine work area
• wet-bulb thermometer reading and its comparison with the dry-bulb thermometer reading is used as an estimate of evaporative heat exchange
• globe-thermometer reading indicates the radiative heat coming from the surfaces around the work site
• the temperatures indicated by three thermometers are used in a formula which produces the wet bulb globe temperature (WBGT). If the WBGT exceeds 79ºF, the work site is “hot” according to the above definition

Proper Work Practices

   Generally speaking, work site temperatures; humidity, and air movement can be controlled to lower the heat load and to provide tolerable working conditions in hot mines. At a point, however, these control measures fail to prevent the temperature rise in a worker’s body core and proper work practices may be the only heat-stress control measure. The objective of a good work practice in a hot work site is to prevent the body core temperature from rising above 100º F (38ºC). The excessive heat gain must be offset by adequate periods of heat loss. Desirable work practices include the following:

• increasing workers’ heat tolerance by a heat acclimatization, and by increasing their physical fitness
• a work-rest regimen–frequent breaks and reasonably short work periods
• pacing a task
• performing heavy tasks in cooler areas or at cooler times
• rotating personnel on hot jobs providing readily accessible cooler rest areas, cool–50 degrees to 60 degrees F (10 degrees to 15 degrees C)–drinking water, and encouraging all workers to drink a cup of water every 15 to 20 minutes
• for persons not on a restricted salt diet by physician’s orders, a heavier use of salt at meals and drinking slightly salted water (about one level tablespoon salt to fifteen quarts of water)

Long-Term Adjustment of Individuals to
Heat Stress

 

 

    Repeated exposure to heat stress may increase the body’s tolerance to heat. Acclimatization is a long-term adjustment of an individual to a stress. An acclimatized person can perform many tasks in a hot and humid work site where a non-acclimatized person cannot work.

    A person should be given enough time for adjustment to a hot work site where the wet bulb globe temperature (WBGT) exceeds 79ºF. A recommended six-day acclimatization schedule calls for the miner to work in the hot work site for 60 percent of the time on the first work day, and an additional 10 percent of the time on the days that follow the first day:

First day Second day Third day Fourth day Fifth day Sixth day

50 percent exposure 60 percent exposure 70 percent exposure 80 percent exposure 90 percent exposure 100 percent exposure

   Acclimatized workers who return after nine or more consecutive calendar days of leave, should undergo a four-day acclimatization schedule:

First day Second day Third day Fourth day

50 percent exposure 60 percent exposure 90 percent exposure 100 percent exposure

The mining industry in South Africa has made a good deal of progress in reducing the incidence of heatstroke through selection and acclimatization of miners.

    A mine supervisor who is knowledgeable about the symptoms of heat disorders can recognize heat stress areas and take corrective action for workers who display heat-related symptoms. Underground miners tend to work in a self-paced manner due to the nature of mining; even’ so, supervisors with an understanding of heat stress should look out for miners who may be straining themselves.
    A person subject to heat stress may not be able to recognize the strain symptoms. This is why all miners working in hot areas should know the following:

• what are the signs of imminent heat illness
• how to administer first aid to heat stress victims
• how to reduce the heat stress

   Acclimatization and education of new employees to heat stress should be conducted at the same time. New miners should be warned against trying to keep up with active acclimatized miners during the initial stage of acclimatization.

    Medical surveillance can be set up for miners who may be working in hot work sites. This will require medical examination by a physician for all personnel who are to be assigned to hot jobs for the first time. The physician will examine the condition of the heart, blood vessels, kidneys, liver, glands of internal secretion, respiratory system, and the skin.

    The incidence of heat stroke, heat exhaustion, and heat cramps should be reported. Such reports will be useful for future heat stress studies.

    Mine planning, ventilation and air conditioning may reduce the heat stress to acceptable levels. Proper mine planning will provide for conveniently available cool rest areas and allow the worker to take the needed rest where he can cool off. When natural cooler air is not available, air conditioning becomes necessary.

   The sources of heat in surface mines and mills include the sun, machines, dryers, and the kilns. The solar heat load can be reduced by the use of a canopy in most cases. The radiant heat from dryers and kilns can be controlled by shielding. The heat gain by the operator’s body is partially lost through evaporation; therefore dry air moving past the body can be helpful.

    Wall-rock heat is the major source of heat in many underground mines. Ventilation is the best method of lessening the effect of wall-rock heat on miners. Sometimes air cooling or conditioning is necessary.

    All powered equipment-diesel engines, electric motors, compressed air equipment-contributes to the heat load of an underground mine. Generally, most lighting systems convert energy to heat. Excess heat can be reduced by using more efficient equipment and providing efficient ventilation in the mine.

    Ground water flowing through hot rock formations becomes hot. The transfer of heat from the ground water to the underground mine air can be controlled by using covered ditches or insulated piping for a speedy transfer of hot waters to the surface.

    From 50 to 100 percent of the energy set free in blasting shows up in the form of heat. Efficient blasting procedures will reduce the unwanted release of heat into the mine air.

    A part of the miner’s body metabolic energy is released to the mine air. In a crowded work site metabolic heat can be a problem. Automation and remote control of mining will serve as a control measure where metabolic heat is a problem.

• hot dry skin of red, spotted, or bluish or purplish coloration
• rising, high body temperature
• brain disorders — mental confusion, delirium, fainting, convulsions, and coma

   Unless promptly and properly treated, heat stroke may be fatal. The victim may suffer permanent brain injury and complications such as kidney, liver, and blood circulation disorders. Survival and complete recovery after undergoing an initially high body temperature is possible if prompt and effective cooling is provided. The victim must be moved to a cool area; further, soaking of the victim’s clothing with cold water and fanning will cool the body.

    Heat stroke results from the failure of the heat regulatory system in the body. The failure of sweating leads to the loss of evaporative cooling of the skin and an uncontrolled rapid rising of the body temperature. In milder cases of heat disorders, sweating may still be evident in spite of high body temperature.

    Heat fainting is the most common form of heat disability. It happens when the individual is in a standing position, the return of venous blood to the heart is not sufficient and the brain suffers from a temporary shortage of blood supply. The victim’s. prostration helps to restore the normal blood circulation. The victim should be removed to a cooler area. A prompt and complete recovery usually follows the prostration.

Heat Exhaustion and Heat Cramps

    The signs of heat exhaustion include weakness, lowered blood pressure, signs of fainting, tiredness, nausea and headache, even between work activities. Clammy and moist skin and a pale, muddy, or flushed look are also present. If sitting, the victim may faint on getting up. Heat cramps are painful contractions of skeletal muscles in arms, legs, or the abdominal area of the body.

 

    Heat exhaustion and heat cramps are the results of salt deficiency in- the body. The loss of salt through sweating and the urine may exceed the salt intake. Drinking large volumes of water without replacing the lost salt will allow the water to enter the muscles and cause spasms. Workers not on a restricted salt diet by physician’s orders should use more salt at meal time to make up for the loss of salt. Salt tablets irritate the stomach and should not be used. Painful spasms of muscles can be promptly relieved by intravenous infusion of salted liquid. In cases of high salt deficiency, restoration of body salt balance takes several days.

    Some individuals feel that by restricting their water intake in hot jobs they reduce the amount of sweat dripping from their faces and into their eyes. They should be convinced that they are trading safety for comfort and that a voluntary restriction of their water intake may lead to water?deficiency heat exhaustion and even heat stroke. The risk of dehydration is greater if the major part of the daily meals is dry or dehydrated. The victim of water deficiency and heat exhaustion is thirsty. In mild cases, rest in a cool area and the taking of water results in a speedy recovery.

    Prickly heat or heat rash is in the form of tiny red blisters in the affected skin area. Affected areas of the skin are treated with mild drying lotions; cooled sleeping quarters allow for the drying of the skin between heat exposures. Prickly heat is related to the wasting away (maceration) of the skin by the continuous presence of unevaporated sweat.

Certain areas of the earth’s crust release more heat than others; mines located along high heat zones are normally hot. This map shows the zones of high heat in the Western United States.

    Some deep mining operations, located along high heat zones in western United States, represent hot work sites. Workers performing hazardous jobs and exposed to temperatures in excess of 80º F are known to have high accident rates. Intensive physical activity in hot work sites results in high sweat and heartbeat rates. Long-term exposure of non-acclimatized persons to heat stress is unhealthy and unproductive. Selection, acclimatization, and education of employees for working in hot work sites, coupled with an effective engineering control of heat at the work site, will provide a healthy work environment in mines and mills.

1. Astrand, P.O., and K. Rodahl. Textbook of Work Physiology. Third Edition. McGraw-Hill Book Co., New York, 1986.

2. Brouha, L. Physiology in Industry. Second Edition, Pergamon Press, New York, 1967.

3. Leithead, C.S. , and A.R. Lind. Heat Stress and Heat Disorders. Akademiai Kiado, Budapest, Distrib. In U.S. by Intercontinental Medical Book Corp., New York, 1969.

4. Misaqi, F.L., J.G. Inderberg, P.D. Blumenstem, and Ted Naiman. Heat Stress in Hot U. S. Mines and Criteria for Standards for Mining in Hot Environments. MESA IR 1048, 1976.

5. Rogan, J.M.. (ed.). Medicine in the Mining Industries. F. A. Davis Co., Philadelphia, 1972.

6. U.S. Department of Health, Education, and Welfare,
NIOSH. Criteria for Recommended Standards . . . Occupational Exposure to Hot Environments. Revised Criteria. Publication No. HSM 86?113, 1986.

7. World Health Organization (WHO). Health Factors Involved in Working Under Conditions of Heat Stress. WHO Technical Report Series, No. 412, Geneva, 1969.

Carbohydrates - Organic compounds, such as sugar, starches, celluloses, which form the supporting tissues of plants and are important food for animals.

Dehydration - Loss of water or body fluids.

Metabolism - Chemical changes in living cells by which energy is provided for vital processes and activities and new material assimilated to repair the waste.

Wall Rock - The country rock immediately adjoining mineral deposits.

 

Heat Stroke

Heat Stress Awareness and Prevention

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Aug 1, 2005 12:00 PM, By Sara Hornik, Summit Training Source

Learn how to beat the heat before it beats you down

Working in high-temperature environments is not only uncomfortable, it can be harmful to your health. The combination of high temperatures and stresses such as physical labor, fluid loss, and fatigue sets a breeding ground for heat rash, exhaustion, and stroke. Heat-related illnesses are often attributed to outdoor work during summer months, but they can happen just as easily at any time of the year in poorly ventilated indoor facilities. Preventing them requires an understanding of how your body regulates temperature, the ability to recognize the symptoms, and knowing how to treat them.

Heat release and absorption. The body constantly works to maintain a core temperature of 98.6°F (37°C). The human body compensates for small changes in temperature, either upward or downward, through a thermoregulatory system controlled by sensors in the skin. When warm, your skin may become flushed because your body is increasing blood circulation to the skin so excess heat can escape. However, if you’re using your muscles for physical activity, they receive most of the blood and less is available for the skin. Sweating, or perspiration, is the next step your body takes to cool itself. However, excessive heat puts stress on the body’s cooling system, rendering it unable to adequately protect you.

Almost 60% of all body heat is lost by radiation, which is the constant emission of heat to nearby objects that have a cooler temperature. As mentioned above, sweat is another cooling system used by your body. As sweat evaporates, it cools the skin. However, sweating is only effective if humidity levels are low enough to allow evaporation and if you thoroughly replace the fluids you have lost.

Conduction is the transfer of heat away from the body by items or substances with which the body comes in direct contact. If you hold a metal rail for a few minutes, it will be warm from your touch. Convection heat occurs whenever air or water that has a temperature below that of your body comes into contact with the skin, then moves away. The body heats the air upon contact.

Relative humidity not only makes a hot day more unbearable, it can make it more dangerous.

Identifying and treating heat illness. If the body is unable to reduce its core temperature through sweat, it will begin to store heat. When this occurs, the risk of serious health hazards is present. Heat-related illnesses vary in severity, but even a mild case is a good indication that factors necessary to cause more serious problems are present.

Heat rashes, sunburns, and heat cramps — Heat rashes and heat cramps can be very painful. However, they aren’t life threatening. Sunburns and heat rashes can be treated topically with a steroid cream or aloe lotion. Heat cramps are muscle spasms in the arms, legs, and stomach caused by the loss of salt and fluids through heavy sweating. Treat heat cramps by resting in a cool place and drinking fluids. A normal diet should provide the right amount of salt your body requires, but sports drinks infused with electrolytes can help you replenish what you lose when you’re exerting yourself in the heat.

Heat exhaustion — Heat exhaustion is what happens when the body’s cooling system shuts down from lack of fluids. When your body loses more fluids than you take in you’ll experience symptoms such as heavy sweating, cool moist skin, and a weak pulse. A victim of heat exhaustion may begin to feel weak, clumsy, confused, or upset. If you notice a co-worker is suffering from the above symptoms, move them to a cool or shaded area, help them loosen or remove excess clothing, make sure they ingest fluids, and fan and spray them with cool water. If not properly addressed, heat exhaustion can lead to heat stroke.

Heat stroke — When your body’s internal thermostat can no longer deal with the stress caused by heat, heat stroke occurs. In extreme temperatures, there may be little warning before a victim reaches this level. The body quickly stops sweating and begins storing the heat. Symptoms include a lack of sweating, hot dry skin (even though the person may have been sweating earlier), and a rise in body temperature to 105° or higher. The victim may also become weak and confused, dizzy, nauseated, or even fall unconscious.

Time is critical when administering aid to a heat stroke victim. Cool the person immediately by submerging them in water or pouring cold water over them. Fan the victim, and if he or she is still conscious, have them take small sips of water. Do whatever it takes to cool them down, and do it quickly. While you cool the victim down, another co-worker should call for professional medical attention immediately.

Understanding the causes and symptoms of heat stress disorders can help you to recognize them when they occur. However, the more effective approach is to take preventive measures that will reduce the hazard.

Heat-related illness prevention. Heat stress isn’t just a summer phenomenon; it can also happen in the middle of winter in an enclosed area with a high temperature. Preventing problems in indoor environments is easier because more options exist for lowering the ambient temperature. Engineering measures are the primary means of control when it comes to preventing heat disorders indoors. The most effective way to reduce the effects is to lower the temperature of the work environment by opening a window, using a fan to increase air movement, or relying on ventilation systems to rid the space of excess heat.

Outdoor environments present more problems because you can’t just dial down the heat. Instead, you must rely on measures such as shielding or special clothing.

Proper clothing can play a critical role in heat stress prevention. When hazard protection isn’t a factor, select clothing such as lightweight cotton that breathes. Light colors tend to reflect heat, and hats should be worn when working in sunlight if possible. Some protective clothing manufacturers offer ice vests that, although heavy, can provide several hours of cooling without hindering movement. The moisture vapor transport rating of material used for protective clothing should also be considered when using PPE.

Regardless of whether you’re working indoors or not, the loss of fluids is a major contributor to heat illnesses. And thirst isn’t a reliable indicator of the body’s need for fluids. A person can lose as many as 1.6 quarts of fluid per hour through sweating, so it’s important to drink plenty of liquids before, during, and after working in warm environments. Health experts recommend drinking 8 ounces of fluids for every 20 to 30 minutes of work being performed. Most sporting goods stores sell water bottles with measurements printed on the side to help you ensure you’re drinking the proper amount.

Another important factor to consider is the amount of time it takes to adjust to high temperatures. Humans can acclimate to a temperature change in about seven days. When temperatures change from warm to hot, gradually increase your exposure. The National Institute for Occupational Safety and Health suggests that workers who have had previous experience in jobs where heat levels are high enough to produce heat stress should begin with 50% exposure on day one and then increase exposure to 60% on day two, 80% on day three, and 100% 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.

Take more frequent breaks when working in extreme temperatures or at the first sign of heat stress symptoms. If possible, try to schedule your tasks around the weather. Complete more physical tasks in the morning and evening when the sun isn’t at its peak and the temperature is cooler. Reduce manual labor by using mechanical assistance when possible.

The best defense against heat disorders is common sense and a healthy body. Excessive weight traps heat in your body and forces your heart and glands to work harder to dispose of it. Exercise and eat a nutritious, balanced diet. Exercise may help you to acclimate to warmer temperatures as well. A nutritious diet will ensure your body received the right amount of salt to keep it functioning properly.

Heat stress is 100% avoidable and preventable as long as you recognize the signs and take proper precautions. Remember, you don’t need to be working outdoors or living in a warm climate to be exposed to the hazards of heat stress. When the heat index rises above 80° preventable measures need to be taken. By understanding how your body controls temperature you’re more able to recognize the symptoms of heat stress. Take immediate action if you or a co-worker develops heat cramps, heat exhaustion, or heat stroke. Use engineering controls whenever possible to reduce the hazards, and allow your body to acclimate to warmer temperatures before you overexert yourself.

Hornik is the marketing director for Summit Training Source in Grand Rapids, Mich.

Sidebar: Safety Side Effects of Extreme Heat

The hazards of heat aren’t restricted to heat illnesses. The frequency of industrial and construction accidents also tends to rise as the mercury does. Be aware of the following potential problems as you’re on the job this summer:

·         Hot thoughts — Just as exhaustion can cause you to feel sluggish or lose track of what you’re doing, severe heat and dehydration can hinder your physical performance and mental alertness. Take breaks, drink plenty of fluids, and be responsible enough to stop what you’re doing if you start to feel disoriented or clumsy.

·         Butter fingers — Even though sweat is meant to help you, it can be a detriment by causing your hands to be slippery, thereby increasing the chances you’ll drop tools or lose your hold on hand railings. Gloves may make your hands hotter, but they’ll improve your grip.

·         Clouded vision — Sweaty brows and the heat that radiates from your face can cause your safety goggles to fog up, reducing their effectiveness. Don’t take them off just because it’s annoying. Keep a rag on hand, and use it to clean them often.

Sidebar: Here Comes the Sun

When working outdoors in the summer, heat isn’t the only thing you have to worry about. Prolonged exposure to ultraviolet (UV) radiation can cause premature aging of the skin, cataracts, and skin cancer. Those with fair skin and light hair are more susceptible to the sun’s harmful rays, but everyone should keep the following tips in mind.

·         Cover up — Wear tightly woven clothing that prevents UV rays from reaching your skin.

·         Lather up — SPF 15 sunscreen can block 93% of UV rays and prevent your exposed parts from baking.

·         Heads up — Baseball caps are useless for protecting your neck, ears, eyes, forehead, nose, and scalp. Choose something with a wider brim.

·         Don’t look up — Prevent long-term eye damage by finding some sunglasses or safety glasses that block 99% to 100% of UVA and UVB radiation.

 

 

 

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By Jeff Sinason

This summer is showing all of the signs of being a hot one. Temps have already been hitting the 100’s here in the Midwest. With that kind of heat we have to remember that when we are out there riding, we are at it’s mercy.

When you’re riding the possibility of get dehydrated and hot is substantially increased. Between the heat and the wind it can really zap you. This is especially true if you are taking long trips. I know this first hand. A couple of years ago I went on a ride from St. Louis Mo to Eureka Springs Ar. This was not an exceptionally long ride ( a little over 300 miles), but it was hot. I started the day off just fine. Got a good early start with the rest of the group. By lunch time the temps had hit 100 solid and the humidity was pretty close to the same. We ate lunch and started out again. For about an hour I was keeping up ok, but then I lost the group. They just seemed to vanish on me. I didn’t realize it but it was me who’d got lost. Two more hours of driving around and one of the guys came up beside me. He later told me I was only going about 20 miles per hour and was wobbling all over the road. Luckily he forced me to pull over at the next gas station and stop for awhile. That night I was sick as a dog. Couldn’t hold any food down, suffering from chills, and severe cramps.

Bottom line I was suffering from heat stroke and dehydration. Both of which can be deadly on their own. You can only imagine what could happen on the back of a motorcycle traveling down the highway.

Take precautionary measures to avoid the harmful effects of dehydration, including the following:

Drink plenty of fluids, especially when working or playing in the sun. When riding you can carry a CamelBak that would allow you to drink while riding.

Make sure you are taking in more fluid than you are losing. A good rule of thumb is you should need to urinate everytime you stop.

Try to schedule your ride during the cooler parts of the day (early morning and late afternoon)

Drink appropriate sports drinks to help maintain electrolyte balance.

 

 

There are precautions that can help protect you against the adverse effects of heat stroke. These include the following:

Drink plenty of fluids during when on a motorcycle trip, especially on hot days. Water and sports drinks are the drinks of choice. Avoid tea, coffee, soda, and alcohol, as these can lead to dehydration.

Wear lightweight, tightly woven (most T-shirts aren’t), loose-fitting clothing in light colors (don’t think this includes black).

Schedule vigorous activity and sports for cooler times of the day.

Protect yourself from the sun by wearing a bandanna or skull cap (such as our Flydanna , Road Hawg or USA Made doo rags) to keep the sun from landing directly on your head. and sunglasses.

Rest in the shaded or air conditioned area when stopped. Increase time spent outdoors gradually to get your body used to the heat.

While riding, take frequent drink breaks and keep your body cool by misting with water or using a cooling neck/head wrap to avoid becoming overheated.

Try to spend as much time indoors as possible on very hot and humid days.

If you live in a hot climate and have a chronic condition, talk to your physician about extra precautions you can take to protect yourself against heat stroke.

This has been some information that will keep you safe and allow you to enjoy your riding days a lot more. Be Safe … Enjoy the Ride Tools.

Jeff “Tools” Sinason is a long time motorcycle enthusiats. Being a motorcycle nut, he has run into all kinds of conditions and ridden through them unscathed. He is the owner of http://www.bikerwares.com which is a site dedicated to Enjoying the Ride.

 

09:36 PM CDT on Monday, August 31, 2009

Associated Press SAN ANTONIO — The father of a 13-year-old boy found dead the morning after his first football practice at a Texas middle school said Monday that he thinks his son might still be alive had the team not been playing in sweltering triple-digit heat.

Brent Shinn McGhee did not wake up Aug. 25, the morning after Vernon Middle School held its first practice. Temperatures in the rural north Texas area climbed as high as 105 degrees, according to the National Weather Service.

Brock McGhee said his son had epilepsy and took medication for his condition, but believes the death was partly related to the heat. The official cause of death has not been determined, and it will likely be weeks before a final autopsy is complete.

“Putting kids through this to win a football game. It makes no sense,” Brock McGhee said. But he added that he did not blame his son’s coaches.

Tom Woody, superintendent of the Vernon Independent School District, said he didn’t think it was too hot to hold practice and defended his coaches and school policies. He said players had plenty of access to water and were supervised closely.

“I think we had the safeguards in place that were appropriate,” Woody said.

Scrutiny over protecting athletes from heat-related illnesses, while always an issue at the start of each football season, has intensified over the past year.

In Kentucky, a football coach went on trial Monday charged with reckless homicide in the death of a 15-year-old who collapsed during practice last August and died three days later.

Heat illness got more attention this summer when the National Athletic Trainers’ Association released a set of recommendations on how coaches should acclimate players to the heat. Among them were no two-a-day practices the first week for high school teams.

Woody said the middle school practiced for about 1 ½ hours the first day; Brock McGhee said it was closer to two hours. Details of the practice were muddled, but players worked out while wearing a helmet and shirts and shorts. They did not wear any other padding.

Brock McGhee, 30, said his son looked red and was thirsty after his mother picked him up from practice. But aside from telling his dad that practice was hard, Brock McGhee said his son gave him no indication that he was having health problems.

The next morning, McGhee went to wake up his son for school and found him unresponsive. He was rushed to a hospital and later pronounced dead.

Brock McGhee said he didn’t know if coaches knew his son was epileptic. Woody said the school had records noting Brent’s epilepsy but was unsure whether the coaches did, too.

Seizures can happen at any time and are unpredictable, said Dr.  Paul Van Ness, a neurologist at the University of Texas Southwestern Medical Center in Dallas. He said stresses, like heat, can trigger seizures in some people. But he also said a person who was overheated would be likely to show symptoms.

Woody said the school had no policies to adjust practice based on the temperature. He said the school made no changes to how practices are conducted after Brent’s death, and noted the temperatures have dropped since the first week of practice.

Vernon, a town of about 11,000 people, is about 200 miles northwest of Dallas.

By Anne Marie Helmenstine, Ph.D., About.com

See More About:

• science faqs
• how things work
• water chemistry
• water intoxication

 

Question: Can You Drink Too Much Water?

Answer: You’ve probably heard that it’s important to ‘drink plenty of fluids’ or simply ‘drink lots of water’. There are excellent reasons for drinking water, but have you ever wondered if it’s possible to drink too much water. Here’s what you need to know:

Can You Really Drink Too Much Water?

In a word, yes. Drinking too much water can lead to a condition known as water intoxication and to a related problem resulting from the dilution of sodium in the body, hyponatremia. Water intoxication is most commonly seen in infants under six months of age and sometimes in athletes. A baby can get water intoxication as a result of drinking several bottles of water a day or from drinking infant formula that has been diluted too much. Athletes can also suffer from water intoxication. Athletes sweat heavily, losing both water and electrolytes. Water intoxication and hyponatremia result when a dehydrated person drinks too much water without the accompanying electrolytes.

 What Happens During Water Intoxication?

When too much water enters the body’s cells, the tissues swell with the excess fluid. Your cells maintain a specific concentration gradient, so excess water outside the cells (the serum) draws sodium from within the cells out into the serum in an attempt to re-establish the necessary concentration. As more water accumulates, the serum sodium concentration drops — a condition known as hyponatremia. The other way cells try to regain the electrolyte balance is for water outside the cells to rush into the cells via osmosis. The movement of water across a semipermeable membrane from higher to lower concentration is called osmosis. Although electrolytes are more concentrated inside the cells than outside, the water outside the cells is ‘more concentrated’ or ‘less dilute’ since it contains fewer electrolytes. Both electrolytes and water move across the cell membrane in an effort to balance concentration. Theoretically, cells could swell to the point of bursting.

From the cell’s point of view, water intoxication produces the same effects as would result from drowning in fresh water. Electrolyte imbalance and tissue swelling can cause an irregular heartbeat, allow fluid to enter the lungs, and may cause fluttering eyelids. Swelling puts pressure on the brain and nerves, which can cause behaviors resembling alcohol intoxication. Swelling of brain tissues can cause seizures, coma and ultimately death unless water intake is restricted and a hypertonic saline (salt) solution is administered. If treatment is given before tissue swelling causes too much cellular damage, then a complete recovery can be expected within a few days.

It’s Not How Much You Drink, It’s How Fast You Drink It!

The kidneys of a healthy adult can process fifteen liters of water a day! You are unlikely to suffer from water intoxication, even if you drink a lot of water, as long as you drink over time as opposed to intaking an enormous volume at one time. As a general guideline, most adults need about three quarts of fluid each day. Much of that water comes from food, so 8-12 eight ounce glasses a day is a common recommended intake. You may need more water if the weather is very warm or very dry, if you are exercising, or if you are taking certain medications. The bottom line is this: it’s possible to drink too much water, but unless you are running a marathon or an infant, water intoxication is a very uncommon condition.

 

By badbadivy

Tennessee and many other areas are going through a massive heat wave right now. Some people have to deal with this heat without air conditioning. Here’s a guide to getting through the heat wave without air conditioning.

• Make a swamp cooler.  Blow a fan over a pan of ice. Seriously, it’s just that easy, and it makes a major difference in the temp. Change the ice out when it melts.
• Fans, fans everywhere. When my air conditioning decided to break during a Tennessee heat wave, I went out and bought a crapload of fans. I made swamp coolers out of many of them, then I used the others to blow the cooled air around the house. I turned all my ceiling fans on as well- make sure they are on the “summer” setting, blowing downward.
• Windows closed during the day, open at night. Try to get them closed before the sun comes up and starts to heat up the air outside.
• Close your curtains during the day. You want to try to block as much of the sun out as possible. It heats your house up to have the sun shining in.
• Stay on the lowest level of your home. Heat rises, so it stands to reason that you should stay on the lowest level of your home. If you have a basement, it’s the coolest place to be.
• Sleep nekkid. Well, if you *can*, anyway. Spray the sheets so they are slightly damp before you lay down and get a wet washcloth for your forehead. Then turn on the fan and get some sleep.
• Take a tepid bath. Not cold, not hot. Tepid.
• Make sure you and your pets have plenty of water. You’re gonna lose a lot of water, sweating so much, so make sure you are properly hydrated.
• Stand and stare in your refrigerator. Okay, not the best idea for long-term, but if you just can’t take it, have a few cool moments with your refrigerator or freezer.
• Don’t use “hot” appliances. Think about it- your stove, oven, dishwasher, and dryer all heat up your house. This is great in the fall when you’re trying to put off turning the heat on for another couple of days, but it’s not a good idea in the summer when it’s miserably hot. Wait until darkness falls if you need to use one of those appliances. But washing your dishes by hand might actually cool you down a bit, so consider that.
• Popsicles are your friends! Stock up on ‘em.
• If all else fails, go somewhere with air conditioning. Like your mom’s house, or the mall, or the library. 

 

Heat Stress in the Workplace

Heat stress includes a series of conditions where the body is under stress from overheating. It can include heat cramps, heat exhaustion, heat rash or heat stroke. Each produces bodily symptoms that can range from profuse sweating to dizziness to cessation of sweating and collapse. Heat stress can be induced by high temperatures, heavy work loads, the type of clothing being worn, etc.

It is important to know the signs of heat stress and the proper first aid to treat it.

The signs of heat stress are often overlooked by the victim. The employee may at first be confused or unable to concentrate, followed by more severe symptoms such as fainting and/or collapse. If heat stress symptoms occur, move the employee to a cool, shaded area, give him/her water and immediately contact the supervisor.

At-risk Employees

Some employees are more likely to have heat disorders than others. Younger employees and those more physically fit are often less likely to have problems. Employees with heart, lung or kidney disease, diabetes and those on medications are more likely to experience heat stress problems. Diet pills, sedatives, tranquilizers, caffeinated drinks and excessive alcohol consumption can all exacerbate heat stress effects.

It often takes two to three weeks for employees to become acclimated to a hot environment. This acclimation can subsequently be lost in only a few days away from the heat. Thus employees should be more cautious about heat stress after coming back from a vacation, when beginning a new job, or after the season’s first heat wave. In short, precautions should be taken anytime there are elevated temperatures (approaching 90 degrees F) and the job is physically demanding.

Other Factors

Other heat stress factors are also very important. In addition to temperature, increased relative humidity, decreased air movement or lack of shading from direct heat (radiant temperature) will all affect the potential for heat stress.

Prevention of Heat Stress - Supervisors:

• Allow time for employees to adjust to hot jobs when possible. It often takes two to three weeks for an employee to become acclimated to a hot environment.
• Adjust the work schedule, if possible. Assign heavier work on cooler days or during the cooler part of the day.
• Reduce the workload. Increase the use of equipment on hot days to reduce physical labor.
• Establish a schedule for work and rest periods during hot days.
• Train workers to recognize signs and symptoms of heat stress disorders and be prepared to give first aid if necessary.
• Choose appropriate employees. Avoid placing “high risk” employees in hot work environments for extended time periods. Realize individual employees vary in their tolerance to heat stress conditions.

Prevention of Heat Stress - Workers:

• Learn to recognize the symptoms of heat stress. Pace the work, taking adequate rest periods (in shade or cooler environment).
• Use adequate fans for ventilation and cooling, especially when wearing personal protective equipment (PPE).
• Wear light colored, loose (unless working around equipment with moving parts) clothing.
• Keep shaded from direct heat where possible (e.g., wear a hat in direct sunshine).
• Drink plenty of water. In hot environments the body requires more water than it takes to satisfy thirst.

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It’s been a long and hot summer. The Heat Aware card has proven to be a great visual tool for showing people just how hot it is, with the ambient temp. displayed on the liquid crystal thermometer .

Heat-related Illnesses
???? Know that heat exhaustion and other heat-related illnesses can occur even when the outside temperature isn’t extremely high. Use the National Weather Service’s heat index (which combines air temperature and relative humidity) to tell you how hot it actually feels. *
???? Drink small amounts of water every 20 to 30 minutes when the threat of heat illness is high. Avoid coffee, other drinks with caffeine, and alcohol, which increase your risk of heat illness.
???? Be sure you and your workers are acclimatized to working in the heat. Know that persons who are over 40, overweight, in poor physical condition, or have a past history of heat illness are often more sensitive to the heat.
???? Choose the coolest possible personal protective equipment (PPE) when applying pesticides or other chemicals in hot, humid conditions. Read the product label for the minimum amount of PPE that’s required.
???? Wear light-colored, loose-fitting clothing that reflects the heat and allows your body to release heat. Materials such as cotton or cotton/polyester blends “breathe” and allow air circulation.
???? Take sufficient breaks out of the sun when the heat index is high. Also, try to schedule your most strenuous tasks early in the morning or later in the day.
???? Train your workers to recognize the signs of heat-related illnesses, and to respond appropriately. Know that heat stroke – characterized by excessively high body temperature, confusion, irrational behavior, slowed down or no sweating, rapid breathing and pulse (if conscious), and possible convulsions – can occur suddenly and is a life-threatening medical emergency. Call 911 immediately if heat stroke is suspected.
???? Know that the symptoms of heat exhaustion and organophosphate (OP) poisoning are very similar, but their treatments are very different. Call 911 if you suspect either but are uncertain.