#ToolboxTuesday - Cold Stress Awareness

What is Cold Stress?

Cold stress occurs when wintry temperatures drive down skin temperature, and eventually internal body temperature. When the body is unable to warm itself, serious cold-related illnesses and injuries can occur that may result in permanent tissue damage and death.

A cold environment forces the body to work harder to maintain its core temperature. Four factors contribute to cold stress: 

  • Cold temperatures 

  • High or cold wind 

  • Dampness

  • Cold water

 

Work Environments Affected

Cold stress applies to work environments where workers may be exposed to either artificial or natural cold.

  • Artificially cold workplaces include cold storage rooms, freezers, and refrigerated transportation units.

  • Industries where workers may be exposed to natural cold include fishing, forestry, construction, and the petroleum industry.

  • Accidental or unplanned events include a worker falling into water such as from a boat or breaking through ice (cold water immersion) or a worker becoming stranded outdoors in the cold.

Typical winter weather can quickly create dangerous working conditions with the combination of low temperatures and even moderate winds.

 

Effects of Cold Stress

When your body temperature drops even a few degrees below normal (which is about 98.6°F), you can begin to experience:

  • Uncontrollable shivering

  • Difficulty doing simple things

  • Slurred speech

  • Physical weakness

  • Drowsiness, disorientation and/or confusion

  • Loss of consciousness or fatal illness

A general assessment of contact cooling for exposed skin, particularly the hands, should consider the following when workers are in contact with metal:

  • Below 15°C: Prolonged contact may impair dexterity

  • Below 7°C: Prolonged contact may induce numbness

  • Below 0°C: Prolonged contact may induce frostbite

  • Below -7°C: Brief contact with may induce frostbite

 

 How To Minimize Exposure

Engineering Controls

  • Radiant heaters may be used to warm workers

  • Shield work areas from drafts or wind

  • Steps should be taken to protect workers from wind (or indoors from drafts or forced air from air handling units)

  • Use insulating material on equipment handles when temperatures drop below -1C

  •  Machines and tools should be designed so that they can be operated without a person having to remove mittens or gloves.

Administrative Controls

  • Regular rest breaks in a heated area are recommended for anyone working in the cold -he frequency and duration of breaks depends on the air temperature and wind speed, as well as the degree of physical activity

  • Ensure that heated rest areas, such as a truck cab, tent, or job shack, are available

  • Temperature and wind conditions should be known, e.g., weather report on daily conditions

PPE Controls

To be protected from the cold, workers should dress in layers:

  • Inner layers should trap moisture and wick it away from the body

  •  Middle layers provide insulation

  • Outer layers protect against the wind and weather

 

As work activity and environmental conditions change, workers should be able to easily add or remove layers. If clothing layers do become damp and remain that way, workers should be prepared to replace them before becoming chilled and hypothermic.


What are your go to base layers when working outdoors in cold temperatures?