The best time to think about cold stress safety isn’t when it’s about to snow – it’s actually when it’s still warm out.
“Construction firms and other businesses may start to think about protecting workers against the cold when frigid temperatures and the winter are right around the corner. But we’ve found that oftentimes, that may be too late to start thinking about cold stress prevention,” said Chris O’Hala, director of construction Risk Engineering at The Hartford. “Thinking about cold protection months ahead can prevent serious injuries, illnesses or even death.”
O’Hala added that possible solutions for cold-related risks, like planning for temporary heat or building temporary enclosures, “require very specific planning, equipment and materials.”
A University of Illinois Chicago study found that patients who died from cold temperatures were responsible for 94% of temperature-related deaths.1
“This is due to our body’s inability to manage hypothermia,” said Dr. Mark Williams, a medical director at The Hartford. “Our bodies try to maintain a certain temperature because chemical reactions needed for internal processes can be affected by too much or too little heat. When we’re in cold environments, blood vessels in the periphery constrict to keep the core circulation warm. If those mechanisms fail, blood is preferentially shifted to the brain at the expense of the internal organ’s ability to function.”
What Is Cold Stress?
Cold stress happens when skin temperature and internal body temperature drops. If the body can’t warm itself, the stress can lead to serious illnesses and injuries.2 When a person’s body temperature becomes too low, it can affect their brain function, a person’s ability to move and even cause death. Illnesses and conditions brought on by cold stress can also cause permanent damage in a person’s body, Williams said.
Anyone working in cold weather or conditions is susceptible to cold stress, he added.
“It’s an issue that needs to be taken seriously,” Williams emphasized. “It can lead to serious health problems and may even cause tissue damage or possibly death.”
Where Can Cold Stress Happen?
A common misconception is that cold stress can only happen when someone is outside, but workers face risks indoors and outdoors, Williams emphasized. They can occur in any industry where workers are exposed to the cold. This includes:
- Mail carriers
- Delivery drivers
- Construction workers
- Restaurant workers
- Powerline workers
When you think about an indoor setting, buildings may not be insulated enough, added David DeSilva, head of Construction at The Hartford.
“If a building isn’t insulated enough, it won’t provide warmth or protection from cold elements,” DeSilva said. “And in the construction industry, workers may be at job sites working inside partially constructed buildings – exposing them to the cold. This is a unique risk present in the construction industry that firms need to address if they’re working in the winter.”
Williams added that a worker’s physical fitness and condition is an important risk factor.
“Poor levels of conditioning can result in faster core temperature cooling,” he explained. “Pre-existing conditions, like a prior diagnosis of frostbite, Raynaud’s phenomenon, peripheral vascular disease and diabetes, can also accelerate the risk of injury.”
What Are the Symptoms of Cold Stress?
Cold stress symptoms vary depending on the injury or illness. While there are some common symptoms across different cold stress-related injuries and illnesses, each one can also affect the body differently, Williams said. Some of the common injuries that cold stress can cause include:
- Hypothermia, which can affect brain function and makes a person unable to think clearly or move well
- Frostbite, which damages deeper tissue and can lead to tissue death
- Trench foot, also known as immersion foot, results from prolonged exposure to wet and cold
- Chilblains, which is the inflammation of the small blood vessels in the skin due to repeated cold exposure
When it comes to hypothermia, there are varying levels of severity:3
- Mild hypothermia occurs when a person’s body temperature is between 90 degrees and 98 degrees. Symptoms include shivering, lack of coordination, stumbling, slurred speech and pale skin.
- Moderate hypothermia occurs when body temperature is between 86 degrees and 90 degrees. At this stage, shivering stops but there is reduced breathing and a slower heart rate. A person may be unable to stand or walk and appear confused or irrational.
- Severe hypothermia occurs when body temperature is between 78 degrees and 86 degrees. A person experiences muscle stiffness and an irregular pulse. They can also be very sleepy and have extremely cold skin.
When a person has frostbite, they lose feeling and color in the impacted area. Frostbite commonly affects a person’s:4
Symptoms of frostbite include reduced blood flow to the hands, feet, fingers or toes. This can cause numbness, tingling or aching.
Trench foot happens after someone’s foot gets exposed to a wet and cold environment for a long time. It doesn’t technically need to be frigid outside for someone to suffer from trench foot. In fact, it can happen at temperatures as high as 60 degrees if the feet are wet.
Symptoms of trench foot include:5
- Skin reddening
- Leg cramps
- Blisters or ulcers
- Bleeding under the skin
If someone is repeatedly exposed to cold temperatures, it can damage the capillaries in their skin. This is known as chilblains. It causes permanent damage and redness, and itchiness can return with additional exposure to the cold.6
Symptoms of chilblains include:7
How Do You Get Rid of Cold Stress?
To reduce injury and illness risk, workers need protection from cold exposure so their core temperature doesn’t fall below 96.8 degrees Fahrenheit, according to the American Conference of Governmental Industrial Hygienists (ACGIH).
Williams emphasized that both employers and employees can take measures to protect against cold stress. This includes:
- Providing appropriate personal protective equipment (PPE) such as windbreakers, hats, gloves and boots for working in a cold environment.
- Monitor workers in cold conditions to make sure they’re taking adequate breaks in a warm environment.
- Implement a buddy system to keep workers accountable for staying safe.
- Provide prompt medical attention to workers who show signs of cold-related illness or injury.
- Train supervisors and workers to prevent, recognize and treat cold-related illness and injury.
- Reduce workers’ time spent in cold environments.
- Rotate workers to provide relief and reduce the physical demands of a job.
- Encourage breaks to warm up when needed.
- Ensure access to warm areas and a place to change out of wet clothes.
- Create a management/employee safety committee that can provide more risk management solutions.
Companies can also use services to keep workers safe on the job. For example, The Hartford offers injury prevention services (IPS) which includes both onsite and virtual services. The goal of the service is to help keep employees safe and healthy on the job, said Margie Snyder, assistant director of solutions for Health Services at The Hartford.
“It’s really a partnership with the business where we take a consultative approach to work with them and learn about their specific risks,” Snyder explained. “If a worker starts to exhibit the symptoms of a cold-related illness or injury, our onsite clinicians can be there to provide quick and necessary treatment.”
Snyder also emphasized that having the appropriate clinical environment is crucial to proper injury care. For example, at one project site, the onsite clinician team was set up in a partially built building, exposing the team and potential employees to the cold. Snyder said the general contractor addressed this by putting in temporary heat solutions.
“This was critical because if we had an employee experience a cold-related injury, we wouldn’t have been able to treat them appropriately in a cold clinic,” she explained. “When you add a back injury or pain into the picture, it can be extremely uncomfortable and painful for an employee to undergo an examination where they’re having to remove layers of clothes in a cold room.”
Creating an appropriate temperature setting for everyone at a work site is “critical to proper care” and productivity, Snyder said.