Cold stress and construction work

During cold weather, construction work requires special consideration. Weather extremes, such as high winds, cold temperatures, ice, snow, sleet and freezing rain present potential hazards to workers. Hypothermia, frostbite, trench foot and chilblains are all illnesses and injuries caused by cold stress.

  • Hypothermia occurs when the body's temperature becomes abnormally low. A body temperature that is too low affects the brain, making it difficult to think clearly or move well, and can eventually lead to death. Early symptoms include shivering, fatigue, loss of coordination, confusion and disorientation. Late symptoms include no shivering, blue skin, dilated pupils, slowed pulse and breathing, and loss of consciousness.
  • Frostbite is an injury to the body caused by freezing tissues. It can cause permanent damage and in severe cases, lead to amputation. Symptoms include reduced blood flow to hands and feet, numbness, aching, tingling or stinging, and bluish or pale, waxy skin.
  • Trench foot is an injury of the feet resulting from prolonged exposure to wet and cold conditions. The wet feet lose heat faster and the circulation begins to shut down, resulting in the skin tissue beginning to die. Symptoms include reddening of the skin, numbness, leg cramps, swelling, tingling pain, blisters or ulcers, bleeding under the skin and gangrene (foot may turn dark purple, blue or gray).
  • Chilblains are caused by the repeated exposure of skin to temperatures just above freezing to as high as 60°F. The cold exposure causes damage to the groups of small blood vessels in the skin. This damage is permanent, and the redness and itching will return with additional exposure. Symptoms include redness, itching, possible blistering, inflammation and possible ulceration in severe cases.

This handout, based on recommendations developed by the National Institute for Occupational Safety and Health (NIOSH), highlights some of the actions that can be taken to reduce the potential for cold stress on construction sites.

Recommendations for employers

  • Evaluate tasks, jobs and job sites for potential exposure to cold.
  • Schedule maintenance and repair jobs in cold areas for warmer months.
  • Schedule cold jobs for the warmer part of the day.
  • Reduce the physical demands of workers.
  • Use relief workers or assign extra workers for long, demanding jobs.
  • Provide warm liquids to workers.
  • Provide warm areas for use during break periods.
  • Monitor workers who are at risk of cold stress.
  • Provide cold stress training that includes information about:
    • Worker risk
    • Prevention
    • Symptoms
    • The importance of monitoring yourself and coworkers for symptoms
    • Medical treatment and first aid
    • Personal protective equipment
    • The potential for alcohol and drugs to increase the effects of cold stress

Recommendations for workers

Workers should avoid exposure to extremely cold temperatures when possible. When cold environments or temperatures cannot be avoided, workers should follow these recommendations to protect themselves from cold stress:

  • Wear appropriate clothing.
    • Wear several layers of loose clothing. Layering provides better insulation.
    • Tight clothing reduces blood circulation. Warm blood needs to be circulated to the extremities.
    • When choosing clothing, be aware that some clothing may restrict movement resulting in a hazardous situation.
  • Make sure to protect the ears, face, hands and feet in extremely cold weather.
    • Boots should be waterproof and insulated.
    • Wear a hat; it will keep your whole body warmer. Hats reduce the amount of body heat that escapes from your head.
  • Move into warm locations during work breaks. Limit the amount of time outside on extremely cold days.
  • Carry cold weather gear, such as extra socks, gloves, hats, jacket, blankets, a change of clothes and a thermos of hot liquid.
  • Include a thermometer and chemical hot packs in your first aid kit.
  • Avoid touching cold metal surfaces with bare skin.
  • Monitor your physical condition and that of your coworkers.

Job site recommendations

  • Keep emergency telephone numbers for medical help in a handy, readily accessible place.
  • Ensure first aid supplies and equipment are readily available.
  • Monitor area weather reports on a regular basis.
  • Keep tool and equipment areas clear of snow, ice or mud accumulations to allow ready access for workers.
  • Keep all access roads clear and open during inclement weather.
  • Use temperature and wind controls, such as barriers and deflectors, as much as possible.
  • Use heated sheds, trailers, vans or portable heaters for break areas where feasible.
  • Provide warm liquids (soup, broth, coffee or tea) to workers on the job site to avoid dehydration.
  • Ensure workers wear the required protective clothing and equipment for the job.


Copyright © 2019, ISO Services, Inc.

This material is provided for informational purposes only and does not provide any coverage or guarantee loss prevention. The examples in this material are provided as hypothetical and for illustration purposes only. The Hanover Insurance Company and its affiliates and subsidiaries (“The Hanover”) specifically disclaim any warranty or representation that acceptance of any recommendations contained herein will make any premises, or operation safe or in compliance with any law or regulation. By providing this information to you. The Hanover does not assume (and specifically disclaims) any duty, undertaking or responsibility to you. The decision to accept or implement any recommendation(s) or advice contained in this material must be made by you.

LC APR 2019-293
171-0843 (6/19)