Back to Basics, Personnel Safety

Back to Basics: Cold Stress

Back to Basics is a weekly feature that highlights important but possibly overlooked information that any EHS professional should know. This week, we examine the dangers of cold stress and how to keep employees safe during winter weather.

As it continues to get colder, it is important to revisit the safety measures that employers can take to make sure that all of their personnel remain safe this winter. According to OSHA, winter weather can present hazards such as slippery roads and surfaces, strong winds, and environmental cold that can lead to illnesses, injuries, or fatalities. All of these can happen if employees are exposed to cold stress.

Types of cold stress

Environmental cold can affect any employee who works in cold air temperatures, including outdoor workers, recreational workers, snow cleanup crews, construction workers, transit and baggage workers, landscapers, police officers, and firefighters. Wind chill can make it feel even colder outside, and it’s in these conditions that employees are at risk of cold stress.

Risk factors for cold stress include wetness and dampness, dressing improperly, exhaustion, predisposing health conditions such as hypertension, hypothyroidism, and diabetes, and poor physical conditioning.

What constitutes as cold stress can differ, but basically, it occurs when the cold weather conditions drive down the skin temperature, and eventually the internal body temperature. Types of cold stress include:

  • Trench foot: A non-freezing injury of the feet caused by prolonged exposure to wet and cold conditions, the symptoms of which include reddening skin, tingling, pain, swelling, leg cramps, numbness, and blisters.
  • Frostbite: The freezing of the skin and tissues that can cause reddened skin to develop gray or white patches in the fingers, toes, nose, or earlobes, along with tingling, aching, a loss of feeling, and blisters.
  • Hypothermia: A condition marked by uncontrollable shivering where the internal body temperature drops below 95°F, that may cause a loss of coordination, confusion, slurred speech, a slowed heart rate, unconsciousness, and possibly death.  

All three of these conditions are extremely serious and employers must take measures to prevent them from occurring. In the cases where they do occur, call 911 immediately in an emergency. Use OSHA’s recommended methods of first aid, including moving the worker to a dry, warm area, removing any wet or damp clothing to replace it with dry clothing, seeking medical attention for rewarming, and providing basic life support when necessary.

Cold stress prevention

OSHA does not have specific standards that cover working in cold conditions, but under the Occupational Safety and Health Act (OSH Act) of 1970, employers are responsible for protecting workers from recognized workplace hazards that can or are causing death or serious physical harm, including cold stress hazards.

Employers should train workers on how to recognize the environmental and workplace factors that can lead to cold stress, the symptoms of cold stress, how to prevent it, and how to administer help to those who may need it. They must be taught how to select proper clothing for cold, wet, and windy conditions. Employees should work in pairs to keep an eye on each other, and they should be provided with warm, sweet, non-alcoholic beverages along with engineering controls such as radiant heaters.

Employers must monitor their workers’ physical conditions, schedule frequent short breaks in warm, dry areas to allow their bodies to warm up, and schedule work during the warmest part of the day. Wind chill should be considered as well when scheduling projects, and OSHA recommends using the National Weather Service (NWS) Wind Chill Calculator to attain that information. OSHA also recommends referencing the American Conference of Governmental Industrial Hygienists (ACGIH) Work/Warm-Up Schedule that was developed to take air temperature and wind speed into account during four-hour shifts.