Back to Basics is a weekly feature that highlights important but possibly overlooked information that any EHS professional should know. This week, we examine how to prepare for winter hazards.
Cold temperatures and seasonal precipitation like freezing rain, hail, or snow can pose winter workplace hazards. What can you expect to see as the new year begins?
The National Weather Service’s winter outlook is a mixed bag, with many parts of the country having equal chances for above-, below-, or near-average seasonal precipitation and temperatures. Given such a hazy outlook, how should you prepare your workforce?
Winter hazards for outdoor workers can include chilblains, frostbite, hypothermia, and trench foot. Even if your worksites are outside the “snow belt,” you need to pay attention to cold weather hazards. Additionally, fuel-burning equipment, heaters, and tools can pose a risk of carbon monoxide (CO) exposure.
Even if your employees are safe inside climate-controlled facilities or offices, they may face winter hazards before they even reach the building.
Hazards like ice and snow on parking lots and walkways can pose slip and fall hazards. “Falls on the same level” cost employers $8.98 billion a year, according to insurer Liberty Mutual. In fact, falls on the same level were the second leading cause of seriously disabling workplace injuries in the insurer’s 2023 Workplace Safety Index.
Also, remove ice and snow from parking lots and walkways.
Commonsense cold weather measures
In general, outdoor workers need to take commonsense precautions to protect themselves from cold weather hazards, which include:
- Wearing several layers of loose clothing. Tight clothing can interfere with proper circulation, and layering provides better insulation.
- Protecting their extremities—ears, face, hands, and feet—by wearing a hat and waterproof boots and gloves.
- Carrying cold weather gear, such as blankets and a change of clothing, extra socks, gloves, a hat, and a jacket.
- Taking breaks in warm locations, such as inside a vehicle or a sheltered or heated area.
Proper clothing should protect the head and exposed limbs, which are major areas of heat loss in cold conditions. A worker’s head and trunk should be warm enough to maintain circulation in the blood vessels of the hands and feet. Keeping enough blood flowing to the hands and feet is the key to preventing frostbite, which, in extreme cases, can lead to amputation.
Frostbite is an injury to a body part caused by freezing. The ears, fingers, nose, and toes are the most vulnerable to injury from frostbite. The symptoms of frostbite appear as reduced blood flow to the hands and feet; numbness; a tingling or stinging sensation; aches; and bluish, pail, or waxy skin. Workers should monitor both themselves and coworkers for frostbite warning signs, which include numbness, pain, stinging, or tingling on or near the affected body part, fingers, or toes.
Frostbite causes a loss of feeling and color in the affected areas. It can permanently damage body tissue and, in severe cases, lead to amputation.
The Alaska Occupational Safety and Health (AKOSH) Division has reported the loss of limbs or extremities due to frostbite in cities and villages, as well as in more isolated areas of the state. AKOSH recommends that workers wear thermal underwear during winter, along with insulated footwear or mukluks with liners, double mittens, and a parka, preferably down-filled with a good ruff. A ruff can provide additional protection against body heat loss.
Moreover, heavy tobacco smokers may have poor circulation and be more susceptible to frostbite, as are tall, thin people. Additionally, alcohol use can cause blood vessels to dilate, leading to a faster loss of body heat—a risk factor for both frostbite and hypothermia. Any of your workers with reduced blood circulation due to health conditions or who aren’t dressed properly for extremely cold temperatures may face an increased risk of frostbite.
If a worker shows symptoms of frostbite, you should get the person into a warm room as soon as possible. Don’t allow a worker to walk on frostbitten feet or toes, unless necessary, as doing so can increase tissue damage. Also, don’t rub or massage the frostbitten area, as this can cause further damage.
Have the worker immerse the affected area in warm but not hot water. (The temperature should be comfortable to the touch for unaffected parts of the body.) AKOSH recommends rewarming limbs in stirred water just above normal body temperature—about 100 to 105 degrees F.
You also can have the worker warm the affected area using body heat. The heat of an armpit can be used to warm frostbitten fingers. You shouldn’t use a heat lamp or heating pad for warming or other sources of heat, such as a fireplace, radiator, or stove, as affected areas may have become numb and could easily be burned.
As frozen limbs are rewarmed, the cooled blood can begin to flow throughout the rest of the body. You should have an affected worker drink warm liquids to prevent such body cooling, as well.
Prolonged exposure to the cold will use up the body’s stored energy, posing a risk for hypothermia. Hypothermia happens when the body begins to lose heat quicker than it can be produced, and it can be fatal. Hypothermia can begin with uncontrollable shivering as the body temperature drops to 95 degrees F.
Have your employees check themselves and coworkers for signs of hypothermia, which can include impaired speech or a lack of coordination. An affected worker may even deny being in trouble, so pay attention to symptoms.
The stages of hypothermia are:
- Impending, when the body’s core temperature has decreased to 96.8 degrees F. The worker’s skin may become pale, numb, and waxy, and the person may show signs of fatigue and weakness. The muscles may tense, and shivering begins. (Shivering is the body’s attempt at creating heat through friction, involving the involuntary contraction and expansion of muscle tissue, and it can occur on a large scale.)
- Mild, when the body’s core temperature has dropped to 93.2 degrees F. Intense and uncontrolled shivering begins. The worker may still be alert, but movements may become less coordinated as the cold causes pain and discomfort.
- Moderate, when the body’s core temperature has dropped to 87.7 degrees F. Shivering may slow or stop completely. Apathy and confusion set in. Speech is slow and slurred. Breathing becomes slow and shallow, followed by drowsiness.
- Severe, when the body’s core temperature is below 87.7 degrees F. The skin may have a blue-gray color, and the irises of the eyes may be dilated. The worker may appear drunk, deny any problems, and even refuse help. The person may gradually lose consciousness. There may be little or no breathing, and the worker may exhibit a lack of response to verbal or painful stimuli. They may even appear dead.
You need to get a worker who’s showing signs of hypothermia out of wet and windy conditions and into a warm room, shelter, or vehicle. You should then remove any wet clothing and warm the worker from the center of the body to the extremities.
The National Institute for Occupational Safety and Health (NIOSH) recommends warming the center of an affected worker’s body, including the chest, groin, head, and neck, using an electric blanket or skin-to-skin contact under loose, dry layers of blankets, clothing, or towels.
Other treatments may include warming an affected worker with warmed objects, such as heat packs, heated rocks, or hot water bottles wrapped in towels or clothing. You may also give an affected worker a warm beverage to prevent further heat loss but only if the worker exhibits a clear level of consciousness with the ability to swallow and if the worker is already starting to warm up.
If a worker fails to recover with first-aid measures, however, you may need to summon emergency medical services and arrange for evacuation.
Chilblains and trench foot
Chilblains and trench foot can lead to permanent and potentially serious injuries. Chilblains, or “chill burns,” are ulcers formed by damaged small blood vessels under the skin that can result from skin exposure to temperatures ranging from just above freezing to as high as 60 degrees F. Cold temperatures can cause damage to the capillary beds, or small blood vessels under the skin. Redness and itching typically occur on cheeks, ears, fingers, and toes. The damage can be permanent, and the redness and itching can return with additional exposure.
Your workers need to wear several layers of loose clothing for insulation because tight clothing reduces blood circulation to the extremities. Boots should be insulated and waterproof, and workers should wear a hat to reduce the loss of body heat through the head.
Workers experiencing chilblains need to slowly warm the skin, avoid scratching, and use corticosteroid creams to relieve itching and swelling. Blisters and skin ulcers need to be cleaned and covered.
Trench foot, also called “immersion foot,” is an injury of the feet resulting from prolonged exposure to wet and cold conditions. Trench foot can occur at temperatures as high as 60 degrees F if the feet are constantly wet. Wet feet lose heat 25 times faster than dry feet. When the feet are wet, the body constricts blood vessels to prevent heat loss, shutting down circulation in the feet. Skin tissue begins to die because of a lack of oxygen and nutrients and a buildup of toxins.
Trench foot may begin as numbness or reddening of the skin but can lead to blisters or ulcers, bleeding under the skin, or even gangrene, when the foot may turn dark purple, blue, or gray.
Workers suffering from trench foot should remove their boots or shoes and wet socks and dry their feet. They should also avoid walking on their feet, which can cause tissue damage.
CO hazards from fuel-burning equipment and tools used inside buildings or semi-enclosed spaces without adequate ventilation claim workers’ lives nationwide, according to the Occupational Safety and Health Administration (OSHA).
Fuel-burning portable generators and space heaters are common sources of CO hazards, as is equipment that uses combustion to operate, such as:
- Gas-powered forklifts and other motorized vehicles,
- Power tools,
- Pumps, and
- Welding equipment.
OSHA recommends that employers install effective ventilation systems, avoid using fuel-burning equipment and vehicles in enclosed or partially enclosed spaces, and use CO detectors in areas where CO hazards may exist.
Have a plan to address CO exposures; cold and wet weather hazards at outdoor worksites; and slip, trip, and fall hazards at fixed facilities.