We all know that working in cold conditions can be uncomfortable; but it can also be hazardous and pose serious threats to health and safety.

Whether exposed to cold and windy conditions outdoors or inside refrigerated environments, working in cold conditions can result in cold-related illnesses and injuries such as hypothermia or frostbite. Cold-related illnesses and injuries can lead to permanent tissue damage and even death.

Although our bodies have natural heating systems, they are not designed to stay warm in extremely cold conditions. Protective clothing and safe work practices are required to keep us protected in cold conditions. We’ll discuss these shortly.

Session Objectives

If you have the right information, you can eliminate or greatly reduce the hazards posed by cold conditions. That’s what this training session is about. By the end of the session, you will be able to:

• Understand how the body reacts to cold;
• Recognize some common illnesses and injuries related to cold and respond properly to them;
• Know the factors that may heighten the risks when working in the cold;
• And, take preventive actions to protect yourself.

As we’ll see, prevention may include a number of different measures, from taking breaks to warm up and drink fluids, to wearing the proper protective clothing and equipment.

So, let’s get started.

Cold Workplaces

There are a number of workplaces and work environments where workers can be exposed to cold conditions.

• Construction workers are exposed to cold conditions in environments such as roof work in cold weather.
• Working on bridges near large bodies of water exposes workers to both the cold temperature and high wind.
• Refrigerated rooms, containers, or vessels expose workers to controlled cold environments. These environments will typically not have a wind chill factor.
• Commercial fishermen are exposed to cold weather, cold winds, and cold water.
• Steel structures retain cold temperatures and transfer the cold easily to workers’ bodies.
• And, in unheated warehouses, workers are exposed to cold temperatures.

The Body’s Reaction to Cold

Let’s talk about how our bodies attempt to cope with exposure to cold temperatures so we can better understand cold-related disorders.

• The body tries to maintain an internal core temperature of about 98.6⁰F.
• In cold conditions the body will decrease blood flow to skin and extremities such as arms and legs. This minimizes cooling of the blood by exposure to the outside cold temperatures.

– Blood continues to flow to the vital organs. The body has to keep them warm for you to survive.

– The reduced blood flow to the extremities increases the chance of frostbite.

• Finally, shivering is another response the body will use to generate heat. Shivering increases the body’s metabolic rate. Severe shivering develops when the body temperature has fallen to 95⁰F.

Hypothermia

Let’s look more closely at medical conditions related to cold conditions.

• Hypothermia is a very dangerous condition. It is the progressive loss of body heat with prolonged exposure to cold.
• It accelerates when a person is wet because of sweat or working in a damp environment or areas of high humidity.
• Most cases of hypothermia occur in air temperatures between 30°F and 50°F.
• Significant hypothermia can occur in air temperatures as high as 65°F. It does not have to be extremely cold for a person to suffer from hypothermia. Other risk factors can contribute to hypothermia in warmer temperatures, including wet clothing, lack of clothing, drugs or alcohol, and age.
• Hypothermia can occur in water that is as warm as 72°F. Cold ocean or lake water can easily lead to hypothermia. That’s one of the reasons falling overboard or into the water is such a danger for people who work on vessels or near the water.

Mild Hypothermia

It is important to know the early signs and symptoms of hypothermia. If mild hypothermia goes unnoticed and the person is not treated, serious hypothermia may occur and result in more dangerous health concerns. In cases of mild hypothermia:

• Persistent shivering usually starts early, when core body temperature drops only a few degrees. The victim’s whole body will shiver uncontrollably.
• The victim will have blue lips and fingers. This is a sign that the blood flow to the extremities has been restricted.
• And, hypothermia can result in poor coordination, which can impact safety and increase risks from other workplace hazards.

Moderate Hypothermia

As hypothermia progresses from mild to moderate, victims lose the ability to understand that they are suffering symptoms from overexposure to the cold and should take corrective measures. When working alone, the chance of getting the necessary help is greatly decreased. In cases of moderate hypothermia:

• Victims begin to suffer from mental impairment and confusion and may even think they are actually getting warmer;
• Victims may become disoriented and start to make poor decisions;
• They may not think anything is wrong and decide not to seek shelter and get warm or may become disoriented and unable to find shelter;
• The heart and breathing rates slow down, which decreases flow of blood and oxygen to internal organs, resulting in mental impairment. Victims become weaker and more lethargic; and
• Another obvious sign is slurred speech. Victims begin to lose some basic motor control, and speech is affected.

When working in cold conditions, it is essential to seek help for anyone who exhibits even one of these symptoms.

Severe Hypothermia

• Severe hypothermia resembles death; however, the patient is still alive and needs help right away;
• Victims of severe hypothermia may be unconscious;
• The heart rate may have slowed down to the point where the pulse is irregular or difficult to find;
• The victim will no longer be shivering; and
• There may be no detectable breathing.

A person in this condition is in grave danger.

First Aid for Hypothermia

Until medical help is available, provide first aid. First-aid treatment for a victim of hypothermia involves stopping the cooling process and providing heat to begin rewarming the victim. Here are the steps to follow:

• Hypothermia is a serious condition, and even mild cases can easily get worse. Call for medical help for all cases of hypothermia.
• Then, get the victim out of the cold environment and away from the cold. Immediately move the victim to a warm shelter.
• Next, remove the victim’s wet and cold clothing.
• Do not place the victim in front of a hot fire or stove. Do not apply heated blankets or pads, although a nonheated blanket can be used. If necessary, use your own body heat to aid the warming.
• Rewarm the internal areas first including the neck, chest, abdomen, and groin areas. Arms and legs should be warmed last.
• Wrap the victim in warm, dry, and loose covers.

First Aid (cont.)

• Keep the victim awake and provide warm, sweet, nonalcoholic drinks if the person is alert and can easily swallow. Do not give alcohol or caffeine drinks. Warm water will do.
• If the victim is unconscious, monitor the breathing and heart rate.
• Find a trained person to administer CPR, if needed. Do it yourself if you can’t find a trained person.

Becoming proficient in first aid requires training. Take advantage of any opportunities you have to receive this training and continue to keep your skills up to date.

Frostbite

• Frostbite is a common injury that is caused by exposure to severe cold or contact with extremely cold objects. You may think that frostbite comes only from exposure to cold air temperatures, but that’s not true. Frostbite occurs more readily from touching cold metal objects than from exposure to cold air. This happens because heat is rapidly transferred from skin to metal. It can be more severe if your fingers are wet.
• The body parts most commonly affected by frostbite are fingers, toes, cheeks, nose, and ears.
• Frostbite occurs when skin tissue actually freezes—cells and blood vessels are damaged. The freezing point of skin is approximately 30⁰F. Wind chill can be a significant factor in accelerating the process.
• The reduced blood flow from damaged blood vessels can cause gangrene.
• Another lingering effect is that body parts that have suffered frostbite damage are more susceptible to suffering frostbite in the future.
• Finally, severe frostbite may result in tissue death, which often requires amputation or results in loss of function—so it is a very serious condition.

Frostbite Symptoms

Frostbite symptoms vary. The condition is not always painful. Sometimes victims may not even know they are suffering from frostbite. That’s why careful observation is important.

• Frostbite usually starts with uncomfortable sensations of coldness.
• Then, the victim may feel tingling, stinging, or aching sensations in the areas affected by frostbite.
• The affected part of the body will feel numb and very cold to the touch.
• Initially, the skin will be waxy and appear almost white.
• Finally, in severe cases, this will be followed by heat, redness, swelling, blistering, and a color change to red and then black. Blistering usually takes about 10 days to subside.

First Aid for Frostbite

• Warm frostbitten areas gradually with body heat. Do not put affected body part near a stove or other source of heat. Do not pour extremely hot water onto the area as this can scald the flesh.
• Do not rub the frostbitten area because this can lead to greater tissue damage.
• Water between 102⁰F and 110⁰F can be used to warm the affected area. Pour in some additional warm water at times to maintain the water temperature.
• Apply a sterile dressing to blistered areas. Keep the blisters clean and dry and be careful not to break them.
• Do not thaw frozen tissue that has suffered severe frostbite unless there is no risk of refreezing. Refreezing may cause additional damage.
• And, get medical attention for more severe cases and let hospital personnel thaw the frozen tissue, especially if the affected tissue involves the hands or feet.

Treating frostbite is another issue that is likely to be covered in first-aid training by a certified provider. Seek out that training; it could save a life or prevent an amputation!

Dehydration

• It makes sense that a person can get frostbite working in the cold, but dehydration? Isn’t that a problem that comes from working in hot weather? Usually, yes. But, dehydration is also fairly common for workers in cold conditions.
• We tend to be less thirsty and drink less when we are cold.
• However, hard physical work in the cold can make you sweat, especially if the protective clothing you are wearing is doing its job and keeping you warm. The dampened clothing can also accelerate hypothermia.
• And, dehydration can weaken your body, leaving you even more susceptible to dangerous conditions such as hypothermia.

Dehydration Symptoms

• Thirst, of course, is the most obvious symptom of dehydration, but it can be lessened somewhat in cold weather.
• Dark-colored urine is a sign that you aren’t taking in enough fluids.
• Fatigue is another potential symptom.

Dehydration Prevention

When working in cold conditions, be sure you drink plenty of non-caffeinated fluids, such as water or a sports drink that replaces electrolytes. You can also drink warm fluids such as soup.

• Drink even if you don’t feel thirsty, as a safety precaution, every time you take a break.

Periodic Inspections

Now it’s time to see what you’ve learned. See if you can answer these questions about hypothermia and frostbite. • Which parts of the body are most at risk for frostbite?

• What are the early signs of hypothermia?
• And finally, after calling for medical help, what should you do immediately to treat hypothermia?

Questions?

Let’s pause for a moment and address any questions. What needs to be clarified, or what more would you like to know about:

• The body’s response to cold conditions?
• Medical conditions related to cold, such as hypothermia, frostbite, or even dehydration?
• How to respond to these conditions?

Environmental Risk Factors For Cold Conditions

Now let’s continue with the session by focusing on the risk factors that may make cold conditions even more hazardous.

• Obviously, temperature plays a key role in determining the amount of stress a worker faces in a cold environment. The colder the temperature, the greater the cold-related stress—which means a higher risk for cold-related disorders.
• Wind also contributes to cold stress. Wind chill may often contribute to cold-related illnesses and injuries without workers knowing what hit them. We’ll talk more about wind chill in a moment.
• Working in damp conditions, or working and sweating in cold conditions, also contribute to cold-related disorders. It is important to always stay dry.
• Contacting cold water may result in hypothermia much quicker than working in cold air.
• Finally, water, snow, and ice also present additional hazards, such as slick footing. A slick or icy surface greatly increases the chances of an injury from a slip, fall, and physical contact with a cold, wet surface.

Wind Chill

The information for this chart was taken from the new wind chill chart developed by the National Weather Service. You’ve probably heard of wind chill, but what is it really?

• Wind chill is the combined effect of air temperature and air movement.
• A dangerous situation of rapid heat loss may arise for any workers exposed to a combination of high winds and cold temperatures.
• In this chart, we can see how the “wind chill temperature” drops as the speed of the wind picks up. The National Weather Service also determined when the combination of temperature, wind speed, and exposure time will produce frostbite on humans.
• The teal numbers indicate that a person’s skin can be exposed for 30 minutes before frostbite develops.
• And, the blue numbers indicate that a person’s skin can be exposed for 10 minutes before frostbite develops.

Other Risk Factors

In addition to cold temperatures and windy conditions, there are other risk factors that can contribute to cold-related illnesses and injuries.

• Inadequate or wet clothing increases the risk because wet or damp clothing does not provide sufficient insulation from cold temperatures.
• Drug use or certain medications can inhibit the body’s response to the cold or even impair judgment so that the victim does not realize he or she is suffering symptoms of a cold-related disorder. Avoid drugs, alcohol, caffeine, and cigarettes when working in cold conditions.
• Some diseases or medical conditions, such as a cold, heart disease, asthma, bronchitis, diabetes, atherosclerosis, hypothyroidism, and even poor blood circulation, may increase risk of suffering a cold-related illness or injury. Be sure to have a physical evaluation by a medical doctor before doing work in cold conditions.
• Male death rates in cold conditions are greater than female death rates. Some suspected reasons include body fat composition or other physiological differences. It has also been suggested that males may more often engage in risk-taking behaviors.
• Workers become more susceptible to cold-related illnesses and injuries as they age.
• Exertion in cold can constrict blood vessels in the heart. Workers at risk for heart attacks or those with coronary diseases have an increased risk of heart attack when working in cold conditions.
• Finally, people who are overweight, have had inadequate rest, or are physically unfit are more susceptible to cold-related illness.

Cold Weather Protection

Now that we’ve learned more about the conditions that increase the risk of workers suffering a cold-related disorder, we need to learn about methods to reduce these risks.

• When protecting yourself from cold conditions, it is important to start with engineering controls.
• Then, use administrative controls.
• And finally, use personal protective equipment, or PPE. Do not rely solely on PPE; other measures can provide a great deal of protection.

Engineering Controls

Let’s start with engineering controls. These are often structures or technologies used to reduce risks.

• For instance, heated shelters should be provided for you if you experience prolonged exposure to equivalent wind chill temperatures of 20°F or less. You should remove your outer layer of clothing and loosen other clothing to let sweat evaporate when entering the shelter. In some cases, a change of clothing may be needed. Remember, it is essential to stay dry.

– If you show signs of shivering, frostbite, fatigue, drowsiness, irritability, or euphoria, you should immediately return to the heated shelter.

• Windscreens erected around the work areas can protect you from drafty or windy conditions.
• On-site sources of heat, such as air jets, radiant heaters, or warm contact plates, can be used to protect hands, feet, and faces from frostbite.
• And, use tools and equipment that have thermal insulating materials on the handles. Thermally insulated work surfaces can be employed to prevent workers from having to sit or kneel on cold surfaces.

Administrative Controls

Administrative controls are the policies and work rules the organization provides to help keep you safe.

• Administrative controls for cold conditions include limiting your exposure to the cold by providing additional breaks or by rotating workers on a job. It’s also important to gradually expose yourself to cold conditions—for example, if you are used to working inside, you should not be asked suddenly to work outside for a full day.
• What you do on your break is also important. It’s essential that you get out of the cold, warm up, and rehydrate yourself.
• Don’t skip breaks even when there’s more work to be done. Your health comes first.
• You can also reduce the risks just by scheduling work for the warmest part of the day. Maybe you’ll be lucky enough to feel a warm sun as you work.

Protective Clothing

You are probably used to the idea of putting on warm clothes before going out in the cold, but if you know the proper methods, you can stay warm more easily.

• First, wear several layers of clothing rather than one thick layer. Air captured between the layers acts as an insulator.
• Wear synthetic fibers such as polypropylene next to the skin because these wick away sweat so it does not stay against your skin.
• Cotton does not wick moisture well and can induce hypothermia if wet. Wear it sparingly.

Protective Clothing (cont.)

• If conditions are wet or windy, wear appropriate outer clothing that protects from the wetness and the wind, but still allows some ventilation. Gore-Tex® or nylon materials are often used.
• It’s important to wear hats, hoods, or face covers to prevent heat loss from the head and to protect the ears from the cold. Up to 40 percent of body heat can be lost when the head is exposed!
• Wear insulated footgear that protects against the cold and dampness. Footgear should not be too tight because it will restrict blood flow and contribute to the potential for frostbite. Footgear should be large enough to allow wearing either one thick sock or two thin pairs of socks. Wearing too many socks can tighten the fit and do more harm than good.
• Wear insulated gloves that protect against the cold and dampness. Gloves should not be so tight that they restrict movement and blood flow in the hands. Fingers and hands lose their dexterity at temperatures below 59°F. If dexterity is required to do the job so that gloves cannot be worn, appropriate engineering controls must be instituted.
• Keep an extra change of clothing available in case work clothing becomes wet. When working in temperatures 35°F or below, workers should immediately change clothes and be treated for hypothermia if their clothing gets wet.

Hand Protection

For many jobs, work gloves are required.

• When fine manual dexterity is not required, wear gloves—water-resistant whenever possible. When doing sedentary work, put on gloves in temperatures colder than 60°F. When the work is light, put on gloves in temperatures less than 40°F. When the work is moderate, put on gloves in temperatures under 20°F.
• Tools and machine controls for use in cold conditions should be designed for use by operators wearing bulky gloves.
• If working in temperatures colder than 60°F, limit bare hand work to 10 to 20 minutes. Prolonged work will result in a loss of hand dexterity and control—and that can lead to an accident.
• To continue doing bare hand work in cold conditions, use special measures such as warm air jets, radiant heaters, or contact warm plates.
• Metal handles of tools or machine controls that are used in cold conditions should be covered by a thermal insulating material.
• Prevent contact frostbite when working near metal surfaces that are colder than 20°F by wearing insulated gloves. Avoid direct skin contact with the cold surfaces.

Other Means of Protection

You can also protect yourself through a few other means.

• One is simply staying physically and medically fit. Workers should be medically fit to work in extremely cold conditions, especially workers that have been affected by risk factors such as heart conditions, diabetes, and other serious medical conditions. A doctor’s examination should precede any work in the cold for people at risk.
• Workers should eat high calorie foods when working in cold conditions.
• Consuming warm soups and warm, sweet drinks while at the worksite helps to maintain calorie intake and fluid volume.
• Avoid coffee because it increases water loss and can inhibit circulation.
• Stay in good physical condition through regular exercise, plenty of sleep, and a balanced diet. If you are physically healthy, the stress of work in cold conditions is considerably reduced.

Safe Work Practices

You can also reduce the hazards of working in cold conditions through safe work practices.

• Whenever possible, avoid activities that can lead to heavy perspiration. Remember, sweat can make you cold, and dehydration from sweating can lead to hypothermia.
• Minimize activities that reduce circulation, such as sitting or standing in cold environments for prolonged periods of time. Keep moving.
• Allow a short period of adjustment to the cold before starting on a full work schedule.
• Never work alone in very cold weather—use the buddy system. This is especially important since hypothermia can sometimes fool people into thinking they are fine. Listen to your buddy if he or she thinks you need to warm up.
• Continue to watch for symptoms of cold-related illness, and seek shelter and first aid immediately if symptoms arise.

Exercise

• Now it’s time to test your understanding of the risk factors of working in the cold. From this list, choose the things that can contribute to a cold-related illness or injury.
• Here are the answers. Did you get them all right?

Questions?

• Are there any questions about the risk factors associated with cold-related illnesses and injuries?
• Do you understand the preventive measures that we can take to stay warm and safe?

Key Points To Remember

Now that you know more about the hazards of working in cold conditions and how to minimize them, the rest is up to you. Are you ready to put what you’ve learned into action?

• Can you recognize the symptoms of cold-related conditions such as hypothermia and frostbite?
• Are you prepared to seek help if you experience any symptoms of a condition, or get help for a coworker if you suspect it’s needed?
• Do you know how to reduce the risks and hazards of working in the cold through means such as engineering and administrative controls, and the use of protective clothing and PPE?
• Are you prepared to put safe work practices into action?

Let’s talk about any questions or comments you have.