
Hypothermia commonly occurs during the winter and in cool, damp conditions. It can lead to serious injury, illness—or even death.
On construction sites, where workers are exposed to the elements for extended periods, the risk is especially high. You’ve likely experienced hypothermia before without realizing it. When you shiver in response to the cold, your body is trying to maintain a normal temperature of 98.6°F. That’s the first stage of hypothermia.
How Your Body Reacts to Cold Conditions
| Core Body Temperature | Your Body’s Reaction |
| 98.6°F | You feel normal. |
| 95°F | You begin to shiver (mild hypothermia). |
| 92°F | Shivering stops, reaction time slows, metabolism and thought process slow (moderate hypothermia). |
| 88°F | You become sluggish, skin appears pale or ashen, fatigue sets in (severe hypothermia). |
| 85°F | You may lose consciousness. |
Watch out for signs of hypothermia
At 92 F, your body stops shivering. As your core temperature drops, your heart and breathing rates slow and your blood pressure drops. Your pulse becomes irregular, indicating your heart cannot supply oxygenated blood to your body.
Hypothermia can affect your performance without you knowing it, even in an ambient air temperature of 55 F.
Hypothermia on the Jobsite
Construction workers face unique risks due to the nature of their work:
- Extended exposure to cold, wind, and moisture: Tasks like roofing, framing, concrete pouring, and excavation often require long hours outdoors.
- Sweating during physical labor: Even in cold weather, exertion causes perspiration. Wet clothing combined with wind chill accelerates heat loss.
- Limited access to warming stations: Remote or large-scale sites may lack heated shelters or vehicles nearby.
- Inadequate clothing: Workers may wear heavy gear for protection, but not all clothing is moisture-wicking or layered properly for temperature regulation.
Even at an ambient temperature of 55°F, hypothermia can impair performance and judgment—putting workers at risk for accidents involving tools, machinery, or falls.
A Jobsite Scenario
Imagine this: You’re working on a framing crew in late November. The morning starts off cold, so you layer up. By mid-morning, you’re sweating from lifting and hammering. Your clothes are damp. By afternoon, the wind picks up and the temperature drops. You stop shivering, feel sluggish, and start making mistakes. You forget measurements, misplace tools, and feel disoriented. These are signs of hypothermia—and they can lead to serious injury if ignored.
How to Prevent Hypothermia on Construction Sites
- Dress in layers: Start with moisture-wicking base layers (synthetic or wool), add insulating layers (fleece or wool), and finish with a waterproof, wind-resistant outer shell. Do not choose cotton for your outer layer, since even wet wool is a better insulator than dry cotton.
- Use jobsite-approved gear: Choose workwear designed for cold environments—insulated gloves, thermal socks, and boots with moisture barriers.
- Take scheduled warm-up breaks: Rotate workers through heated trailers, vehicles, or warming stations. OSHA recommends frequent breaks in cold weather.
- Stay hydrated: Drink water regularly. Dehydration increases the risk of hypothermia.
- Drink warm fluids in moderation: Choose caffeine-free teas, hot chocolate or hot water with lemon. Drinking warm fluids will help you maintain a body temperature of 98.6 F
- Keep spare clothing on site: If your clothes get wet, change immediately.
- Use portable heaters safely: Ensure proper ventilation and follow manufacturer guidelines to prevent fire or carbon monoxide risks.
What to Do If You Suspect Hypothermia
- Remove wet clothing immediately.
- Put on dry, warm layers.
- Get to an external heat source, such as a blanket or heater.
- If possible, place your clothing in a dryer or near a heat source to preheat it before putting it on. (A word of caution: Never place anything on a heat-generating device or interfere with air circulation around the device. This could cause a fire or malfunction.)
- Drink warm, non-caffeinated fluids.
- Apply a warm compress, but not to your extremities. Heating your arms and legs can force cold blood back to your heart, lungs and brain. Also avoid heating pads and heat lamps, as direct heat can cause an irregular heartbeat.
- Seek medical attention if symptoms worsen or if the person becomes unconscious.
By understanding the risks and taking proactive steps, construction crews can stay safe and productive—even in harsh winter conditions.
Reach out to Brett Findlay, SVP, Business Risk Specialist, at BFindlay@OneGroup.com for more information on how to protect your employees from hypothermia.
This content is for informational purposes only and not for the purpose of providing professional, financial, medical or legal advice. You should contact your licensed professional to obtain advice with respect to any particular issue or problem. Please refer to your policy contract for any specific information or questions on applicability of coverage.
Please note coverage can not be bound or a claim reported without written acknowledgment from a OneGroup Representative.
Copyright © 2024 Applied Systems, Inc. All rights reserved.








