Cold Stress: The Dangerous Four

When the body is unable to warm itself, serious cold-related illnesses and injuries known as cold stress may occur, and permanent tissue damage and death may result. The most common types of cold stress include trench foot, frostbite, hypothermia, and chilblains. Increased wind speed, wetness, or dampness, even from body sweat, can facilitate rapid heat loss from the body. Cold stress occurs by driving down the skin temperature, and eventually the internal body temperature.

How Can Cold Stress be Prevented?
Although OSHA doesn’t have a specific standard that covers working in cold environments, employers still have a duty to protect workers from recognized hazards, including cold stress hazards, that cause or are likely to cause death or serious physical harm in the workplace. For a full scope of prevention practices and techniques for employers, reference our recent post on winter safety practices. Below we will detail the four most dangerous and common cold stress conditions that every worker should know and be able to identify.

Cold Stress Danger #1: Immersion/Trench Foot
Trench foot is a non-freezing injury of the feet caused by prolonged exposure to wet and cold conditions. This was first discovered in World War I, when soldiers got trench foot from fighting in cold, wet conditions in trenches without extra socks or boots to keep their feet dry. Since this condition killed thousands of unfortunate soldiers, awareness about increased, resulting in a push for better foot care in soldiers and outdoor workers alike. It generally occurs in 30°F and 40°F weather, although can occur in temperatures as high as 60°F if feet are constantly wet. Injury occurs because wet feet lose heat 25-times faster than dry feet.

Trench foot can affect small portions of the feet, but also can extend over the entire foot, including the toe. Prolonged cold and wetness can result in loss of nerve function, gangrene, and amputations. Symptoms of trench foot include but are not limited to:

• Reddening skin
• Tingling
• Pain when exposed to heat
• Blotchy skin
• Persistent itching or prickliness
• Numbness and heaviness
• Skin tissue that dies and falls off

The best way to prevent workers from being at risk from this condition is to educate workers on proper personal protection equipment (PPE). Workers should choose footwear that keeps feet dry and comfortable, despite how wet outside conditions may be. Additional steps workers can take include:

• Change into clean, dry shoes and socks as frequently as possible during the work shift.
• Wear waterproof sock liners to keep feet dry.
• Sprinkle talcum powder on feet, toes, and the insides of shoes or boots.
• Rotate between two or more pairs of work shoes or boots between shifts.
• Wash and dry feet thoroughly after work.

Cold Stress Danger #2: Frostbite
Frostbite is caused by the freezing of the skin and tissues. Frostbite can cause permanent damage to the body, and in severe cases can lead to amputation. The risk of frostbite is increased in people who are tall and thin, those with medical conditions resulting in reduced blood circulation, and people who are not dressed properly for extremely cold temperatures.

Symptoms of frostbite include reddened skin develops gray/white patches in the fingers, toes, nose, or ear lobes; tingling, aching, a loss of feeling, firm/hard, and blisters may occur in the affected areas.

When a worker realizes frostbite may be setting in, the following is recommended to minimize damage:

• Protect the frostbitten area by wrapping loosely in a dry cloth and protect the area from contact until medical help arrives.
• Don’t rub or massage the affected area, because rubbing causes damage to the skin and tissue.
• Don’t apply snow or water – and don’t break blisters.
• Don’t try to re-warm the frostbitten area before getting medical help; for example, don’t use heating pads or place in warm water. If a frostbitten area is rewarmed and gets frozen again, more tissue damage will occur. It’s safer for the frostbitten area to be rewarmed by medical professionals.
• Give warm sweetened drinks if alert (no alcohol as that causes blood vessels to dilate).

Cold Stress Danger #3: Hypothermia
Hypothermia occurs when the normal body temperature (98.6°F) drops to less than 95°F. Exposure to cold temperatures causes the body to lose heat faster than it can be produced. Prolonged exposure to cold will eventually use up the body’s stored energy. The result is hypothermia, or abnormally low body temperature. Hypothermia typically happens at very cold temperatures, but it can occur even at cool temperatures (above 40°F) if a person becomes chilled from rain, sweat, or immersion in cold water.

An important mild symptom of hypothermia is uncontrollable shivering, which shouldn’t be ignored. Moderate to severe symptoms of hypothermia are loss of coordination, confusion, slurred speech, heart rate/breathing slow, unconsciousness and possibly death. If you suspect someone may be suffering from hypothermia you can do the following after calling 911:

• Move the worker to a warm, dry area.
• Remove any wet clothing and replace with dry clothing. Wrap the entire body (including the head and neck) in layers of blankets and use a vapor barrier (a tarp or garbage bag).
• If medical help is more than 30 minutes away:
  • Give warm sweetened drinks if alert (no alcohol), to help increase the body temperature.
  • Place warm bottles or hot packs in armpits, sides of chest, and groin.

Cold Stress Danger #4: Chilblains
Chilblains are caused by the repeated exposure of skin to temperatures just above freezing to as high as 60 degrees F. The cold exposure causes damage to the capillary beds (groups of small blood vessels) in the skin. This damage is permanent and the redness and itching will return with additional exposure. The redness and itching typically occurs on cheeks, ears, fingers, and toes.

Symptoms of chilblains include the following ailments:

• Redness
• Itching
• Possible blistering
• Inflammation
• Possible ulceration in severe cases

Workers suffering from chilblains should avoid scratching by using corticosteroid creams, slowly warming the skin, and keeping all blisters clean and covered.

Take Out the Guesswork in Safety
These four life altering and threatening cold stress related conditions can be caused by multiple lapses in safety and awareness in the workplace. As we move into colder months, it’s important to know what signs to look for – and when to get help.

Clarion Safety has over 30 years of experience in best practice safety standards and liability expertise. If you’re looking to assess the labels and signs in your workplace, take the guesswork out and contact one of our safety professionals today for the latest guidance and services.

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