Working in cold, windy and wet conditions can cause cold stress in workers. Cold stress refers to cold-related illnesses that happen when the body can no longer maintain its normal temperature. Cold stress illnesses include hypothermia, frostbite, trench foot, and chilblains. To ensure worker safety, employers should implement cold weather health and safety programs, including cold weather engineering controls and employee training.
Engineering Controls for Cold Weather
Cold weather working conditions require engineering controls such as:
- Warm and dry break areas
- Shielding employees from wind
- Radiant heaters
- Insulating material on equipment handles when temperatures fall below 30°F.
Employee Training for Cold Weather
Employees should receive training on the following topics:
- Safe work practices for cold weather
- Dressing appropriately for cold weather
- Recognizing and treating cold stress illnesses.
The remainder of this article provides additional information on these topics.
Safe Work Practices for Cold Weather
- Stay hydrated by drinking warm, sweetened beverages.
- Schedule work during the warmest parts of the day.
- Use the buddy system so workers can monitor each other for signs of cold stress.
- Schedule frequent breaks in a warm and dry environment. The American Conference of Governmental Industrial Hygienists (ACGIH) developed a Work/Warm-Up Schedule for 4-hour shifts that provides guidelines for scheduling work breaks based on weather conditions. The document also provides guidance on when to cease non-emergency work.
- Provide cold weather safety kits stocked with blankets, chemical hot packs, dry clothing (including socks), hand and foot warmers, a thermometer, and first aid information on treating cold stress illnesses.
Dressing Appropriately for Cold Weather
- Dress in layers. Workers should dress in three different layers and have an outer protective layer. The inner layer should wick moisture away from the skin and allow for ventilation. The best choice is long johns made of silk or synthetic materials. Be sure to avoid cotton. A light insulating middle layer should absorb sweat and promote insulation. A thin wool sweater is an excellent choice. A heavier insulating outer layer should keep warmth inside. A heavier fleece or wool sweater is a good choice. Finally, workers should have a windproof and waterproof outer layer to protect them from the elements.
- Wear loose-fitting clothes. Good blood flow is critical in cold weather conditions so avoid tight clothing that restricts circulation.
- Wear waterproof and insulated boots. Boots should not restrict circulation and should be big enough to wear two pairs of socks and still have wiggle room for feet. If work takes place in snowy conditions, wear gaiters to prevent snow from slipping into boots and wetting feet.
- Layer socks. Socks should be layered just like clothing. Wear a thin polypropylene sock under a pair of wool socks. All workers should have extra pairs of socks in case feet get wet.
- Protect the head and face. Most body heat is lost through the head, so a winter hat is critical. Pairing a toque with a balaclava is an excellent choice because it protects delicate facial tissue and the neck area. This arrangement should also allow for a hard hat to be worn if needed.
- Protect hands. Frostbite and chilblains often strike in the hands. If technical work must be performed with hands, workers should wear thin, high-quality gloves under mittens—removing the mittens only when necessary. Extra pairs of gloves should be available in case they get wet.
Recognizing and Treating Cold Stress Illnesses
The symptoms and treatment for cold stress illnesses are provided below. A laminated copy of first aid information (such as this document produced by the National Institute for Occupational Safety and Health) should be included in all cold weather safety kits.
Hypothermia Symptoms
- Mild Hypothermia: shivering, lack of coordination, slurred speech, and pale, cold skin. Body temperature may range from 89 to 95 degrees Fahrenheit.
- Moderate Hypothermia: cessation of shivering, mental confusion, slow and shallow breathing, slow and weak pulse, and an inability to walk or stand. Body temperature will range from 82 to 89 degrees Fahrenheit.
- Severe Hypothermia: severe muscle stiffness, sleepiness or unconsciousness, extremely cold skin, and an irregular or difficult to find pulse. Body temperature will be lower than 82 degrees Fahrenheit.
Hypothermia Treatment
Hypothermia is potentially life-threatening and requires immediate medical attention. Cases of severe hypothermia must be treated at a hospital as numerous problems can occur during recovery. If medical care isn’t immediately available, follow the steps below.
- Move the victim to a warm room or shelter.
- Remove wet clothing.
- Warm the center of the body first (chest, neck, head, and groin) using an electric blanket or skin-to-skin contact under dry layers of blankets, clothing, or towels.
- If the victim is conscious, warm sugary beverages may help increase the body temperature. Do not give alcohol or caffeine.
- Monitor the victim’s body temperature. Once body temperature has risen, keep the victim dry and wrapped in a warm blanket.
- If there is no pulse, begin CPR.
Frostbite Symptoms
As frostbite worsens, victims will no longer feel the area, which is why it is essential to monitor the color and look of the skin using the guidelines below.
- Early Stages: Skin is pale yellow or white and may itch, sting, burn, or feel like “pins and needles.”
- Intermediate Stages: Skin becomes hard and looks shiny or waxy. There may be little or no feeling in the area.
- Late Stages: Skin is hard and cold to the touch and darkens quickly. Skin may appear blue and then black.
Frostbite Treatment
Treatment at a hospital is recommended. Medical professionals will be able to assess frostbitten areas and determine the best course of treatment. Immediate first aid measures include the following.
- Get to a warm room as soon as possible.
- Unless necessary, do not walk on frostbitten feet or toes.
- Immerse the affected area in warm (not hot) water or warm the affected area using body heat. Do not use a heating pad, fireplace, or radiator for warming.
- Do not massage or rub the frostbitten area as this may cause additional damage.
Trench Foot Symptoms
- Tingling and itching
- Pain
- Swelling
- Cold and blotchy skin
- Numbness
- Prickly or heavy feeling in the foot
- Blisters
- After becoming warm, the foot may be red, dry, and painful.
Trench Foot Treatment
Medical attention is required so a doctor can determine the stage of trench foot and prescribe the appropriate treatment. Long-term treatment will depend on the severity of the case. If left untreated, trench foot can lead to gangrene and possibly amputation. First aid treatment includes the following.
- Remove shoes/boots and wet socks.
- Dry and warm the feet slowly.
- Avoid walking on the feet as this may cause tissue damage.
Chilblains Symptoms
- Small, itchy red areas (usually on feet or hands)
- Swelling/inflammation
- Burning sensation
- Blistering (possible)
- Ulceration (severe cases)
Chilblains Treatment
Chilblains usually get better on its own. Seek medical care if pain is unusually severe, if an infection is suspected, or if symptoms don’t improve after a few weeks. First aid treatment includes the following.
- Slowly warm the skin.
- Use corticosteroid creams to relieve itching and swelling.
- Avoid scratching.
- If blisters or ulcers form, keep them clean and covered.
Cold Stress Can Be Avoided
If you are interested in learning more about appropriate cold weather gear for your team, contact us today.