Centers for Disease Control

and Prevention

National Institute for Occupational 

Safety and Health

Summary 

Workers, both indoors and outdoors, in services, transportation, 

agriculture, construction, and other industries may be exposed to 

environmental cold stress that can 

lead to thermal discomfort and in 

some cases even severe injuries, illnesses, or death. The National Institute for Occupational Safety and 

Health (NIOSH) recommends that 

employers implement a cold-related illness and injury prevention 

program that includes preventive 

measures such as using engineering controls, establishing work/

rest schedules, training workers 

about the hazards of working in 

cold environments, and providing 

appropriate cold-weather gear.

Preventing Cold-related Illness, 

Injury, and Death among Workers

that is purposefully kept cold, poorly 

insulated, or without heat. People who 

have previously experienced frostbite, 

sedentary workers, and those with 

poor circulation may be especially 

susceptible. For indoor workers, work 

in cold, damp conditions can be uncomfortable and may lead to declining work performance (i.e., a decline 

in cognitive function and dexterity) 

or result in cold-related illness or injury. Cold-related conditions can also 

worsen musculoskeletal injuries and 

vascular disorders. For outdoor workers, what constitutes cold stress can 

vary across different areas of the country. In regions where workers are unaccustomed to winter weather, near 

freezing temperatures are considered 

factors for cold stress. Whenever outdoor temperatures drop substantially 

and wind speed increases, heat leaves 

the body more rapidly. According to 

the American Conference of Governmental Industrial Hygienists (ACGIH®) Threshold Limit Values (TLV®), 

workers should be protected from exposure to cold so that the deep core 

temperature does not fall below 96.8°F 

(36°C) and to prevent frostbite to body 

extremities [ACGIH 2019]. Serious 

health problems can occur when the 

body is unable to stay warm enough.

Cold-related Illnesses 

and Injuries

Cold-related illnesses and injuries include chilblains, trench foot, frostbite, 

and hypothermia. 

Chilblains. Chilblains are the painful inflammation of small blood vessels in 

the skin that occur in response to repeated exposure to cold but nonfreezing temperatures. Small blood vessels 

in the skin may become permanently 

damaged by cold temperatures, resulting in redness and itching during additional exposures. Symptoms of chilblains include redness, itching, possible 

blistering, inflammation, and possible 

ulceration in severe cases.

Description of 

Exposure

Workers who work in cold environments may be at risk of cold stress. Exposure to cold can be an uncomfortable 

and potentially dangerous situation. 

Health emergencies can occur in people who work outdoors or in an area 

Photo by MarianVejcik/Getty Images
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Trench Foot. Trench foot is an injury of the feet after prolonged exposure to wet and cold-related conditions. Trench 

foot occurs because wet feet lose heat faster than dry feet. To 

prevent heat loss, the body constricts blood vessels in the feet, 

and then the skin tissue begins to die. Symptoms of trench foot 

include reddening of the skin, numbness, leg cramps, swelling, 

tingling pain, blisters or ulcers, bleeding under the skin, and 

gangrene (e.g., foot turns purple, blue, or gray).

Frostbite. Frostbite is an injury caused by freezing of the skin 

and deeper tissues, resulting in the loss of feeling and color in 

the affected areas. Frostbite can permanently damage body tissues, and severe cases can lead to amputation. Examples of risk 

factors for frostbite include contact with metal or water, dehydration, diabetes, smoking, alcohol abuse, sedating or judgment impairing medications, and prior history of frostbite. 

Symptoms of frostbite include numbness; tingling or stinging; aching; and bluish or pale, waxy skin. During treatment 

of frostbite and trench foot, avoid rubbing or putting pressure 

on affected areas, since that can damage tissue. 

Hypothermia. When exposed to cold temperatures, the body 

loses heat faster than it can be produced. Prolonged exposure to cold causes internal body temperature to drop, resulting in a condition called hypothermia. Hypothermia affects 

brain function, making the victim unable to think clearly or 

move well (i.e., they may be unable to protect themselves from 

hazards, or experience slips, trips, and falls). This makes hypothermia particularly dangerous because a person may not 

recognize the symptoms and will be unable to make life-preserving decisions. Symptoms of hypothermia can depend on 

how long a person has been exposed to cold temperatures and 

individual variability.

Hypothermia Symptoms and First Aid

Early symptoms include shivering, fatigue, loss of coordination, confusion, and/or disorientation. 

Late symptoms include no shivering, blue skin, dilated pupils, 

slowed pulse and breathing, and/or loss of consciousness.

If hypothermia is suspected, medical assistance should be requested immediately (e.g., call 911). Begin first aid by:

1. moving the worker to a warm room or vehicle, 

2. removing wet clothing, 

3. covering their body with loose, dry blankets, clothing, or 

towels (may use skin-to-skin contact or warm bottles or 

hot packs in armpits, sides of chest, and groin to increase 

body’s temperature), and

4. providing warm, non-alcoholic beverages if the worker is 

conscious. 

If the worker has no pulse, cardiopulmonary resuscitation 

(CPR) should be provided and continued during the warming attempts, until the person responds or medical aid becomes available. Chest compressions should not be performed for patients who manifest an organized rhythm on 

a cardiac monitor (e.g., automated external defibrillator 

[AED]), even if they have no palpable pulses and no other signs of life. The worker should be handled very gently 

and kept horizontal, because when cold, the heart is prone to 

ventricular fibrillation with any disturbance. Severely hypothermic patients have been known to survive neurologically intact after long periods (over an hour) in a state of “suspended animation” [State of Alaska DHSS 2014].

Photo by ilkercelik/Getty Images

Case Reports

Indoor Environment: Airline Catering 

Facility

In an airline catering facility cold room (approximately 40°F), meals were assembled at workstations in shifts 

lasting 3–8 hours [Ceballos et al. 2015; NIOSH 2014]. Because preparations sometimes required fine manual dexterity (e.g., thinly slicing fish, decorating with small garnishes), the workers preferred wearing thin gloves instead of 

thicker, better insulated gloves. The frozen food they handled caused their hands to become cold and numb. Drafts inside the cold room made some areas feel colder than others, 

and air velocities exceeded the recommended guidelines 

of 200 feet per minute (FPM) [ACGIH 2019]. In addition, 

the workers felt that their breaks were not long enough to 

warm up, or to change out of wet or sweat-dampened clothing. An evaluation of the cold room concluded that thermal 

comfort concerns perceived by workers might have resulted from workstation air drafts, insufficient use of personal protective equipment (e.g., better insulated gloves) due 

to dexterity concerns, work practices, and lack of knowledge about good health and safety practices. In an evaluation of a second airline catering facility where the temperature was approximately 40°F, workers reported that they 
3

felt discomfort working in cold temperatures, particularly 

in the freezer or coolers [NIOSH 2015]. The reported findings suggest that language was a barrier to effective training 

and communication regarding workplace safety and health 

because employees came from 18 countries.

Outdoor Environment: Long Haul 

Driving Along Highway

In the winter of 2009, a 56-year-old male truck driver went 

to the emergency room seeking care [Alaska Trauma Registry]. He had come to Alaska after a long haul drive through 

Canada. Along his route, he had stopped to change a fuel filter. He accidentally splashed diesel fuel on his gloves, which 

froze to his hands as he worked outside along the highway. 

After arriving at his destination, he had to spend a night at 

the hospital receiving treatment for his frostbitten hands.

Outdoor Environment: Sheep Ranch

At 3:00 p.m., a 58-year-old woman (who was wearing tennis 

shoes, blue jeans, sweater, jacket, and gloves) and her husband left their sheep ranch headquarters to round up their 

animals and bring them in for protection from a major snow 

storm that was developing [NIOSH 1990]. The woman separated from her husband to chase down a second flock of 

sheep. Shortly afterward, a high wind arose and created 

whiteout conditions in the area. The husband was unable to 

locate the woman and returned to the ranch to obtain additional help. At 10:00 p.m., the sheriff ’s department, local 

volunteer fire department, emergency medical service, and 

search and rescue units became involved in the search. The 

search continued until 3:00 a.m., when it was decided to wait 

for daylight. At 7:45 a.m., the body of the woman was found. 

Autopsy results showed she had died from hypothermia.

Recommendations

Whether in an indoor or outdoor environment where cold 

stress conditions are possible, employers and workers should 

be aware of symptoms of cold-related illness and injury, not 

only in themselves but also in their coworkers, and be prepared to immediately notify their supervisor, provide first 

aid, and seek prompt medical assistance (e.g., call 911). 

Prevention is the best way to avoid cold-related illness and 

injury. Employers and workers should follow the NIOSH 

recommendations below to reduce the risk of cold-related 

illness and injury. 

All Cold Environments

Employers should: 

 Train supervisors and workers to prevent, recognize, and 

treat cold-related illness and injury.

 Provide training in a language and vocabulary that the 

workers understand.

 Reduce workers’ time spent in the cold environment.

 Reduce the physical demands of workers (e.g., use relief 

workers or rotate extra workers in and out of work for 

long, demanding jobs).

 Ensure access to warm areas and a place to change out of 

wet clothes.

 Encourage employees to take breaks to warm up when 

needed.

 Monitor workers in cold conditions and initiate a buddy 

system.

 Include a medical and environmental thermometer and 

chemical hot packs in first aid kits.

 Participate in joint management/employee safety committees.

 Provide appropriate cold weather gear such as hats, gloves, 

and boots for work in cold environments.

 Provide wind protective clothing based on air velocities.

 Provide prompt medical attention to workers who show 

signs of cold-related illness or injury.

Workers should:

 Take regular breaks to warm up.

 Monitor their physical condition and that of coworkers.

 Stay hydrated by drinking lots of water; warm beverages 

may help increase body temperature.

 Stay well nourished by snacking on high carbohydrate 

foods.

 Avoid touching cold metal or wet surfaces with bare skin.

Photo by sorn340/Getty Images
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 Report signs and symptoms of cold-related illness and injury to supervisors and medical staff immediately.

 Participate in joint management/employee safety committees.

 Carry extra cold weather gear, such as a change of clothes, 

in case work clothing gets wet.

 Wear several layers of loose clothing for better insulation; 

take layers off if you begin to sweat and put them back on 

when you cool down. Inner layers should be wool or synthetic fabrics to wick away moisture; outer layers should 

be wind and water-resistant. 

 Avoid wearing wet clothes.

 Protect the ears, face, hands, and feet by wearing hats, 

gloves, socks, and boots.

Indoor Environments 

Employers should: 

 Install equipment to reduce drafts and condensation.

 Provide warm water or dry air heaters outside cold rooms 

for workers to warm their hands.

 Minimize air velocity and not exceed 200 FPM.

 Perform preventative maintenance on a regular schedule and make repairs if heating systems are not working 

properly.

 Rotate employees to different tasks after every break.

 Minimize work requiring manual dexterity in cold rooms.

 Provide glove alternatives for workers inside cold rooms 

(e.g., glove liners or fingerless gloves to wear under plastic gloves).

Photo by wabeno/Getty Images

Outdoor Environments 

Employers should: 

 Create a plan for assessing and acting on workplace hazards posed by sudden weather changes, such as dropping 

temperatures or increasing wind speeds.

 Schedule normal maintenance and repairs in cold areas 

for warmer months when possible.

 Schedule cold jobs for the warmer part of the day.

 Ensure that workers traveling through or working in remote areas have appropriate cold-weather survival equipment (e.g., emergency communications equipment such 

as a personal locator beacon or satellite phone).

Acknowledgments

The principal contributors to this publication were Brenda 

Jacklitsch, PhD, MS, of the NIOSH Division of Science Integration (DSI) and Diana Ceballos, PhD, MS, CIH, of the 

Harvard T.H. Chan School of Public Health (formerly with 

NIOSH).

Suggested Citation 

NIOSH [2019]. Preventing cold-related illness, injury, and 

death among workers. By Jacklitsch B, Ceballos D. Cincinnati, OH: U.S. Department of Health and Human Services, 

Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. DHHS (NIOSH) 

Publication No. 2019-113, DOI: https://doi.org/10.26616/

NIOSHPUB2019113.

References

ACGIH [2019]. TLVs® and BEIs® based on documentation 

of the threshold limit values for chemical substances and 

physical agents & biological exposure indices. Cincinnati, 

OH: American Conference of Governmental Industrial 

Hygienists.

Alaska Trauma Registry, http://dhss.alaska.gov/dph Emergency/

Pages/trauma/registry.aspx. Accessed November 2016.

Ceballos D, Mead K, Ramsey J [2015]. Recommendations to 

improve employee thermal comfort when working in 40°F 

refrigerated cold rooms. J Occup Environ Hyg 12(9):D2216.

NIOSH [1990]. Wife of a sheep rancher was fatally injured 

while attempting to round up a flock of sheep. Cincinnati, 

OH: U.S. Department of Health and Human Services, 

Centers for Disease Control and Prevention, National 

Institute for Occupational Safety and Health. Fatality 

Assessment and Control Evaluation (FACE) Investigation 

Report No. 90CO024.

NIOSH [2008]. NIOSH safety and health topic: cold stress. 

Cincinnati, OH: U.S. Department of Health and Human 

Services, Centers for Disease Control and Prevention, 

National Institute for Occupational Safety and Health, 

www.cdc.gov/niosh/topics/coldstress.

NIOSH [2010]. NIOSH fast facts: protecting yourself from 

cold stress. Cincinnati, OH: U.S. Department of Health 

and Human Services, Centers for Disease Control and 
5

Prevention, National Institute for Occupational Safety and 

Health, DHHS (NIOSH) Publication No. 2010–115, www.

cdc.gov/niosh/docs/2010-115/pdfs/2010-115.pdf.

NIOSH [2014]. Health hazard evaluation report: evaluation 

of ergonomic risk factors, thermal exposures, and job 

stress at an airline catering facility. By Ramsey JG, Musolin 

K, Ceballos D, Wiegand D, Mead K. Cincinnati, OH: U.S. 

Department of Health and Human Services, Centers for 

Disease Control and Prevention, National Institute for 

Occupational Safety and Health, NIOSH HHE Report No. 

2011-0131-3221.

NIOSH [2015]. Health hazard evaluation report: evaluation 

of ergonomic risk factors, acute traumatic injuries, and 

occupational exposures at an airline catering facility. 

By Ramsey J, Kawamoto M, Ceballos D, Wiegand DM. 

Cincinnati, OH: U.S. Department of Health and Human 

Services, Centers for Disease Control and Prevention, 

National Institute for Occupational Safety and Health, 

NIOSH HHE Report No. 2011-0131-3222.

OSHA [2014]. Emergency preparedness and response safety 

and health guidelines — cold stress guide. Washington, 

DC: U.S Department of Labor, Occupational Safety and 

Health Administration, https://www.osha.gov/SLTC/

emergencypreparedness/guides/cold.html.

State of Alaska DHSS [2014]. Cold injuries guidelines. Juneau, 

AK: Department of Health and Social Services, Division of 

Public Health, Section of Emergency Programs, Emergency 

Medical Services (EMS) Program, http://dhss.alaska.gov/

dph/Emergency/Documents/ems/documents/Alaska%20

DHSS%20EMS%20Cold%20Injuries%20Guidelines%20

June%202014.pdf.

Information about Cold Stress can be found on the following website:

https://www.cdc.gov/niosh/topics/coldstress/

1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

CDC/NIOSH INFO: cdc.gov/info | cdc.gov/niosh

Monthly NIOSH eNews: https://www.cdc.gov/niosh/eNews.

Mention of any company or product does not constitute endorsement by NIOSH. In addition, citations to websites external to NIOSH do not constitute NIOSH endorsement of 

the sponsoring organizations or their programs or products. 

Furthermore, NIOSH is not responsible for the content of 

these websites.

This document is in the public domain and may be 

freely copied or reprinted. NIOSH encourages all 

readers of the Workplace Solutions to make them 

available to all interested employers and workers.

As part of the Centers for Disease Control and Prevention, NIOSH is the federal agency responsible for conducting research and making recommendations to prevent work-related illness and injuries. All Workplace 

Solutions are based on research studies that show how 

worker exposures to hazardous agents or activities can 

be significantly reduced.

DOI: https://doi.org/10.26616/NIOSHPUB2019113

DHHS (NIOSH) Publication No. 2019-113

September 2019

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