Most of us have heard of cold-related illnesses such as frostbite, hypothermia, chilblains, and trench foot. All are illnesses related to cold stress. Cold exposure can also cause or worsen other health problems and makes it harder to work safely.
Workers with chronic conditions such as asthma or arthritis are more likely to suffer flare-ups in cold weather. Cold stress also decreases dexterity, coordination, and mental performance, which increases the risk of accidents and injuries.
Working in cold conditions raises the likelihood of sprains and strains because muscles and tendons resist injury less when cold. Low back strains and other musculoskeletal injuries are more common when the body is chilled.
What is Cold Stress?
Cold stress describes how the body responds when it loses heat faster than it can produce it, especially from exposed hands, feet, limbs, or the head. Prolonged exposure is a physical and mental challenge and can lead to cold-related illnesses.
How the body loses heat
Humans lose heat in four main ways:
- Radiation
- Convection
- Conduction
- Evaporation
The best way to avoid cold stress and related illness or injury is to change work habits and use appropriate clothing and equipment. Employers should plan work-rest cycles based on temperature and wind, and provide warming shelters when workers are exposed to below-freezing conditions for extended periods.
The following guidance, adopted by professional industrial hygienists as Threshold Limit Values (TLVs) for cold stress, is a useful reference when establishing work periods and rest breaks. 
When operations run year-round in cold climates, businesses may also consider additional operational protections such as Winter Weather Insurance to help manage weather-related disruption.
Changing Work Habits
How long an employee should work in cold conditions depends on air temperature and wind speed—the colder and windier it is, the shorter continuous work periods should be. Managers should use TLV-based guidance to schedule work and rest.
When workers are continuously exposed to freezing temperatures, warming shelters such as heated tents, trailers, or restrooms should be provided and scheduled into work breaks. Employers should also adjust workloads so workers do not overexert and sweat excessively, which reduces the insulating value of clothing.
Personal Protective Equipment and Cold Weather Gear
Small measures can improve comfort and safety. For example, insulating metal tool handles can reduce cold transfer; protecting tools and reviewing equipment needs may be part of a broader risk plan such as Industrial Equipment and Spare Parts Insurance.
Choose clothing for the expected temperature, wind, and precipitation. Layering is better than a single heavy garment, and outer layers should be removable to avoid sweating too much.
Dressing tips
- Layer clothing for flexible insulation.
- Wear thermal underwear made of polyester or polypropylene to wick sweat.
- The outer layers should insulate and seal at cuffs, waist, and neck but open easily if you become warm.
- If there is rain or snow, use waterproof outerwear.
- Wear a watch cap or ski mask—up to 50 percent of body heat can be lost from the head.
- Keep clothing clean because dirt reduces insulating ability.
- Use waterproof gloves when wet; consider mittens for very cold weather.
- Choose footwear with rubber bottoms, leather uppers, and removable felt insoles; layer socks (a thin synthetic inner layer and a thicker outer layer) and avoid cotton.
- If you need face and eye protection, use separate eye protection and face coverings to reduce fogging.
For heavy outdoor operations or jobs with specialized equipment needs, consider industry-specific risk protections such as Mining Equipment Insurance.
If you are unsure which protective measures or business protections are appropriate, talk to your agent for advice tailored to your operations.
Follow these tips and your company and employees will have added protection from cold injuries and illnesses.
Frequently Asked Questions
What are early signs of hypothermia?
Early signs include shivering, numbness, slurred speech, and poor coordination; seek a warm environment and medical attention if symptoms progress.
How should workers layer clothing for cold weather?
Use a moisture-wicking base layer, insulating middle layers, and a windproof or waterproof outer layer that can be removed if you overheat.
When should a warming shelter be provided?
Provide warming shelters whenever continuous exposure to freezing temperatures is expected or when wind and wet conditions increase cold stress.
How can employers reduce cold-related accident risk?
Adjust work-rest schedules based on conditions, provide proper PPE, train workers on cold signs, and plan for warming breaks to maintain dexterity and alertness.