Working in winter’s extreme cold is a fact of life for many people. If you’re employed in the construction, transportation or energy industries in some North American locations, you’ll likely know what it’s like to have Jack Frost nipping at your nose. You’ll also know how important it is to take cold weather safety precautions.
Workplace winter safety is paramount when you’re outdoors in freezing temperatures. Cold air presents a significant health danger, especially when the wind picks up. The last thing you want is yourself or your workers suffering a life-threatening phenomenon called cold stress. Fortunately, cold stress can be readily managed as long as you take appropriate measures to control and prevent it.
Cold stress is a very real condition recognized by the United States Occupational Safety and Health Administration (OSHA). It’s also known as hypothermia in the medical field. Cold stress happens when your body’s core temperature drops below its normal rate of 98.6 degrees Fahrenheit. With a low core temperature, your body might not be able to naturally warm itself, which leads to permanent tissue damage or even death.
Hypothermia, or cold stress, occurs when low temperatures drive down your skin’s warmth, which progressively cools your inner core. Wind and wetness are the biggest factors causing cold stress. However, other contributing factors amplify a hypothermic situation such as poor overall health, hunger, dehydration and fatigue.
Avoiding prolonged exposure to cold temperatures is your primary defense against cold stress. Having the proper clothing and other personal protective equipment (PPE) designed for cold weather working is equally important if you can’t avoid some exposure to cold conditions. Then, you have to stay as dry as possible under your PPE and do everything you can to block the wind.
Wind chill is extremely dangerous and a leading factor in lowering temperatures at a worksite. It’s the effect of air movement across your body, and it is extremely hazardous to exposed parts like your face and hands. Wind chill also affects your clothed areas, as it creates an increased condition where your body heat radiates through layers of artificial insulation.
There’s an inverse relationship between wind speed and temperature drop. The National Weather Service's wind chill chart shows how quickly temperatures drop as wind velocity increases. Here are some examples of how increased wind can change the temperature you feel when you’re working in the cold.
A wind chill of -67F is excruciatingly cold and potentially deadly, but -67F isn’t the coldest static temperature ever recorded in the United States. That distinction goes to Prospect Creek Camp in Alaska, which saw -80F on January 23, 1971. With a 30 mph wind, the chill would be off the charts.
Alaska might be a winter land of cold wind with ice and snow, but the central parts of the U.S. see their fair share of winter coldness. The average winter temperature in the continental United States is +33.2F, which is slightly above water’s freezing point. However, if you match a +33F static temperature with a 40 mph wind speed, the mercury drops to -13F, which will freeze exposed skin in no time.
Cold stress can happen in relatively warm weather. It’s sure to occur in extremely cold weather unless you take the right precautions to manage yourself and your crew. To help you and your workers stay warm and dry, here are some tips for working in extreme cold.
Safely working in extreme cold is all about heat management. Your body is a natural furnace that converts food to energy. Part of the energy-converting process is regulating your inner core at a healthy +98.6 degrees Fahrenheit. As long as you stay at your ideal body temperature, you’ll be perfectly comfortable all day long. Unfortunately, the weather has other plans.
You can’t control the weather, but you certainly can control what you do while working in extreme cold. These are the main defenses you can employ to stay safe and warm while outside:
You can find other great tips for working in extreme cold from OSHA and the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS). The National Weather Service provides up-to-date information on current weather conditions across the nation as well as accurate forecasts. The NWS also provides first-class information on cold weather safety and how to protect from the cold.
There’s a lot of common sense involved in protecting from the cold. As humans, we’re remarkably adaptable to cold weather climates. Many societies thrive in the cold, and they’ve made some remarkable methods of shielding themselves from extremely low temperatures.
Take the igloo, for example. It’s an ingenious structure built from snow that serves as a highly effective windbreak as well as an insulated environment. People nicely survive inside an ice-formed dome, and they report igloos to be downright toasty.
Your first priority for working in extreme cold is providing shelter. That involves stopping wind chill and raising the temperature if you can. You should always bring your cold-weather work inside rather than unnecessarily suffering it out in the elements.
If you have no option other than to work in extreme cold, then you have to take whatever precautions you have available. That should involve controlling the temperature as much as possible. It also involves isolating yourself and others from the heat-robbing cold.
To effectively protect from the cold, it’s important to understand how physics applies to heat transfer — a science called thermodynamics. These are the three forms of thermodynamic heat transfer:
Thermodynamic heat transfer happens whether you work in the heat or the cold. You can seriously suffer from heat stress just like you can succumb to cold stress. It’s your responsibility to protect yourself and others from thermodynamic heat transfer when you’re working in extreme cold.
Your body works with all three heat transfer forms. You experience convection when your system converts food into energy. You experience conduction when your body warms your clothes. And you experience radiation when your clothed body gives off your hard-earned heat to the frigidly cold air.
Heat always transfers from hot to cold. Nature insists that you’ll always experience thermodynamic heat exchange. It can be a killer in the cold unless you protect yourself from heat loss.
To work with nature instead of against it, you need to keep your internal body temperature at its healthy rate of 98.6F. You protect that by feeding it food and converting it to heat through convection and conduction. You then have to protect your body from radiation heat loss by insulating it with the right clothing.
Other heat loss prevention techniques also play into your safety and comfort. After feeding and insulating yourself, you have to prevent that heat-stealing force called wind chill. By blocking moving air from inside and out, you’ll achieve the best protection from the cold.
Believe it or not, OSHA does not have any specific regulations concerning cold weather limits or laws regarding working in cold temperatures. They don’t have an extreme cold conditions standard. The overriding clause in OSHA governing workplace hazards is the OSH Act of 1970 where section 5 states employer duties. This reference to OSHA cold temperature limits says:
“Each employer shall furnish a place of employment free from recognized hazards that are causing or likely to cause death or serious physical harm to their employees.”
There’s no question that exposing unprotected works to extreme cold could cause serious physical harm or death. No one would argue that. To help both employees and employers function in extreme cold conditions, OSHA provides helpful information about the dangers of working in cold weather and how to minimize risk.
Your danger level increases with each temperature degree drop. You are in far more danger of injury or death when working in 20 below temperatures than right at the freezing level. Extend that cold temperature to 40 below, and you could be in serious peril in a very short time.
There are three main cold-weather injuries that workers can suffer. They range from mild to severe and result from combinations of factors. According to OSHA’s guide to cold stress, workers can experience these effects:
Trenchfoot, frostbite and hypothermia are dangerous forms of cold stress. Each condition can have a long-lasting effect on you or your workers. For a safe and healthy workplace where you’re exposed to extreme cold, there are some simple steps you can do to prevent cold stress injuries.
Without question, the most effective way to prevent cold stress injuries is to remove the threat. Without cold temperatures, there is no risk. Unfortunately, completely removing the threat may not be optional if your livelihood involves working in extreme cold. If so, you have to protect yourself and others from suffering heat loss.
When you’re making a plan to safely work in extreme cold, always consider the physics behind heat loss. Heat always moves to cold. If you can’t raise the ambient temperature, then you have to block body heat from escaping to avoid cold stress. Here are your best ways of preventing cold stress from happening:
Making sure your outdoor working equipment is dependable and won’t break down under the harshest conditions is a smart way to mitigate cold stress. Many workers suffer cold-related injury because their equipment failed. The equipment couldn’t run to provide a heat source, and workers were forced to fix it in extreme cold.
Your chance of cold weather failure is significantly reduced when you rent equipment from The Cat® Rental Store. With over 1,300 equipment rental locations across North America, we can provide extreme cold solutions in frigid environments you’ll find in Alaska, Canada and the northern central states.
Our selection of Cat machinery includes cold-weather performers like graders, loaders and skid steers. We rent excavators that work in the winter as well as power generators that start in the coldest of times and produce life-saving heat. At The Cat Rental Store, we also offer work tool attachments that will plow snow and blow it away.
Contact The Cat Rental Store today for your extreme cold-weather options. Call us at 1-800-RENT-CAT or stop by one of our convenient locations near you.