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Cold Weather Safety and Training Resources 

A common hazard of cold temperatures is cold stress. Cold stress results from a reduction in skin temperature and eventually the body’s internal temperature. As a result, cold-related illnesses and injuries may occur when the body is unable to warm itself. Types of cold stress include immersion/trench foot, frostbite, and hypothermia. Susceptibility to cold-related illnesses can also vary from person to person. Risk factors include wetness/dampness; proper dress; exhaustion; predisposing health conditions such as hypertension, hypothyroidism, and diabetes; and poor physical conditioning.

Hypothermia

Hypothermia occurs when the normal body temperature (98.6°F) drops to less than 95°F. Hypothermia is most likely 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.    

Symptoms of hypothermia include:

Mild Hypothermia: 

• Uncontrolled Shivering

Moderate to Severe Hypothermia: 

• Confusion
• Slurred speech
• Heart rate/breathing slow
• Unconsciousness
• Death

First Aid:

• Call 911 immediately in an emergency. 
• Move the worker to a warm area.
• Remove wet clothing and replace with dry clothing.
• Wrap the entire body (including the head and neck) with blankets, and with something to block the cold (e.g., tarp, garbage bag). Do not cover the face.
• If medical help is more than 30 minutes away:
  1. Give warm, sweetened drinks if alert (no alcohol). 
  2. Apply heat packs to the armpits, sides of chest, neck, and groin.

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. 

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.

First Aid:

• Protect the frostbitten area, e.g., by wrapping loosely in a dry cloth and protect the area from contact until medical help arrives.
• DO NOT rub the affected area, because rubbing causes damage to the skin and tissue.
• Do not apply snow or water. Do not break blisters.
• DO NOT try to re-warm the frostbitten area before getting medical help.

Immersion/Trench Foot 

Trench foot is a non-freezing injury of the feet caused by prolonged exposure to wet and cold conditions. 

Symptoms of immersion/trench foot include: 

• Reddening skin 
• Tingling
• Pain
• Swelling
• Leg cramps
• Numbness
• Blisters

First Aid: 

• Remove wet shoes/boots and wet socks.
• Dry the feet and avoid working on them.
• Keep affected feet elevated and avoid walking. Get medical attention.

To Prevent Cold-Related Illnesses: 

Dress Properly for the Cold

• Proper dress is extremely important in preventing cold stress. The type of fabric worn also makes a difference. Cotton loses its insulation value when it becomes wet. Wool and most synthetics, on the other hand, retain their insulative qualities even when wet. 
• Wear at least three layers of loose-fitting clothing. Layering provides better insulation. Do not wear tight fitting clothing.
  1. An inner layer of wool, silk or synthetic to keep moisture away from the body.
  2. A middle layer of wool or synthetic to provide insulation even when wet.
  3. An outer wind and rain protection layer that allows some ventilation to prevent overheating.
• Wear a hat. Hats reduce the amount of body heat that escapes from your head.
• Use insulated gloves.
• Wear insulated boots or other footwear.

Work Practices

• Stay dry as moisture or dampness can increase the rate of heat loss from the body.
• As it is easy to become dehydrated in cold weather, drink plenty of liquids, avoiding caffeine and alcohol. 
• If possible, schedule work during the warmer parts of the day. 
• Try to work in pairs to keep an eye on each other and watch for signs of cold stress.
• Take frequent breaks in warm areas.

Training: 

Employees should be trained on how to recognize cold-related illnesses, what to do in the event someone is experiencing symptoms of a cold-related illness, and how to prevent cold-related illness. Training should be conducted prior to working in cold environments. To access cold stress safety training, click on the link below. 

CALS Cold Stress Safety Training

Additional Resources: 

UW System Winter Weather Safety Webpage

OSHA’s Winter Weather Webpage

OSHA’s Cold Stress Guide

OSHA Quick Card: Protecting Workers from Cold Stress

NIOSH Fact Sheet: Protecting Yourself from Cold Stress

National Weather Service Wind Chill Calculator