Cold Stress Safety, Protection on the Jobsite

By David DeSilva and Dr. Mark S. Williams

The best time to think about cold stress safety isn’t when it’s about to snow – it’s when it’s still warm out. 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.

Superintendents may start thinking about protecting their crew against the cold during frigid temperatures. Oftentimes, however, that may be too late, especially if the jobsite is in the Northeast, Midwest, Rocky Mountains or parts of the upper Pacific regions of the U.S.

When a person’s body temperature becomes too low, it can affect their brain function and a person’s ability to move. Illnesses and conditions brought on by cold stress can also cause permanent damage to a person’s body. Like planning for temporary heat or building temporary enclosures, possible solutions for cold-related risks require specific planning, equipment and materials, so it’s never too soon to begin a cold stress protection strategy to prevent serious injuries and illnesses on the jobsite.

A common misconception is that cold stress can only happen when someone is outside, but workers face risks indoors and outdoors.

When thinking about an indoor setting, buildings may not be insulated adequately. If this is the case, it won’t provide warmth or protection from cold elements. Oftentimes, crews may be on jobsites working inside partially constructed buildings – exposing themselves to the cold. This is a unique risk present in the industry that field supervisors should address.

A worker’s physical fitness and condition is also an important cold stress risk factor. Poor levels of conditioning can result in faster core temperature cooling, and pre-existing conditions such as a prior diagnosis of frostbite, Raynaud’s phenomenon, peripheral vascular disease and diabetes can further accelerate the risk of injury.

Symptoms of cold stress
Cold stress symptoms vary depending on the injury or illness. While there are common symptoms across different cold stress-related injuries and illnesses, each one can also affect the body differently. Some of the common injuries that cold stress can cause include hypothermia, frostbite, trench foot and chilblains.

When it comes to hypothermia, which can affect brain function and inhibit a person’s ability to think clearly or move well, there are varying levels of severity according to “Cold Stress – Cold-Related Illnesses” from the U.S. Centers for Disease Control and Prevention. Mild hypothermia occurs when a person’s body temperature is between 90-98 F. Symptoms include shivering, lack of coordination, stumbling, slurred speech and pale skin.

There’s also moderate hypothermia when body temperature is between 86-90 F. At this stage, shivering stops. but there is reduced breathing and a slower heartrate. A person may be unable to stand or walk and appear confused or irrational.

Hypothermia becomes severe when body temperature is between 78-86 F, and a person experiences muscle stiffness and an irregular pulse. This is the most concerning level, because a person can also be very sleepy and have extremely cold skin.

When a person has frostbite, they lose feeling and color in the impacted area. It commonly affects a person’s nose, ears, cheeks, chin, fingers and toes — damaging deeper tissues of the body. Symptoms include reduced blood flow to the hands, feet, fingers or toes, causing numbness, tingling or aching.

Meanwhile, trench foot, also known as immersion foot, results from prolonged exposure to wet and cold. This condition 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 F if the feet are wet. Symptoms include skin reddening, numbness, leg cramps, swelling, blisters or ulcers, bleeding under the skin and gangrene.

Chilblains, which is the inflammation of the small blood vessels in the skin due to repeated cold exposure, can cause permanent skin damage and redness. If someone is repeatedly exposed to cold temperatures, the itchiness can return with additional exposure. Symptoms include redness, itching, blistering, inflammation and ulceration.

How to eliminate cold stress
To reduce injury and illness risk, workers need protection from cold exposure. Superintendents can take measures to protect their crew against cold stress by offering training to prevent, recognize and treat cold-related illness and injury, as well as properly monitor jobsites in cold conditions to make sure workers are taking adequate breaks in a warm environment.

It’s imperative that prompt medical attention is provided if workers show signs of cold-related illness or injury. A management and employee safety committee would be helpful, as well as providing risk management solutions before a situation arises. This includes mitigation efforts such as encouraging breaks to warm up when needed, ensuring access to warm areas to change out of wet clothes, reducing workers’ time spent in cold environments and rotating workers to provide relief from the physical demands.

David DeSilva is head of construction, The Hartford’s Middle and Large Commercial division. Dr. Mark S. Williams is a chiropractic physician and medical director with The Hartford.

[Editor’s Note: For more information on cold stress, visit: “Cold Stress – Cold-Related Illnesses” from the U.S. Centers for Disease Control and Prevention]