Cold stress: what OSHA and NIOSH recommend for cold-weather work
Cold stress is what happens when the body loses heat faster than it can make it. Skin temperature drops first, then the core, and the result is frostbite in the fingers, toes, ears and face, trench foot in wet boots, and hypothermia when the core falls far enough to slow the brain and heart. Wind and wetness drive it as much as the thermometer: hypothermia can set in above 40°F in a worker soaked by rain or sweat, and trench foot can occur at 60°F if the feet stay wet. There is no OSHA cold standard; employers are responsible for cold hazards under the general duty clause, and OSHA and NIOSH say the same things about what that means: train the crew to recognize it, schedule the heavy work for the warm part of the day, give warm breaks and warm drinks, use a buddy system, and dress in three loose layers with a hat, insulated gloves and waterproof insulated boots.
Caiman 1353 insulated split cowhide glovesEN 511 221: rated for cold air, cold surfaces and waterWhy is cold stress about more than temperature? The body loses heat four ways: to moving air, to anything it touches, to water, and by evaporation. Wind strips the warm layer of air off the skin, which is what wind chill measures. A cold steel handrail or a frozen pallet pulls heat out through the hands far faster than cold air does. Water conducts heat away from the body many times faster than air, so a wet glove, a sweated-through shirt or a leaking boot undoes the insulation around it. That is why OSHA’s guide puts wetness, improper dress and exhaustion at the head of its risk factors, and why the protective clothing advice is built around layers that wick, insulate when wet, and block wind and rain.
What are the cold stress injuries, and what are the signs?
The OSHA Cold Stress Guide lists three. Any one of them on a jobsite means the worker comes in now.
What do you do for hypothermia and frostbite?
- Hypothermia: call 911 in an emergency; otherwise get medical help as soon as possible. Move the person to a warm, dry area. Remove wet clothes and replace them with dry ones. Cover the body, including the head and neck, but not the face.
- If medical help is more than 30 minutes away: give warm, sweetened drinks if the worker is alert, no alcohol. Place warm bottles or hot packs in the armpits, the sides of the chest and the groin. Never try to give a drink to an unconscious person.
- Frostbite: get medical help. Loosely cover and protect the area from contact. Do not rub the affected area to warm it; that causes more damage. Do not apply snow or water. Do not break blisters. Do not try to rewarm the frostbitten area before getting medical help; it is safer for medical professionals to rewarm it, and a part that is rewarmed and then refreezes is worse off.
- Trench foot: get medical help. Remove wet socks and boots, dry the feet, keep the worker off them.
What are employers expected to do?
- Train workers to recognize cold stress in themselves and each other, to prevent it, and to give first aid. NIOSH lists the training topics: worker risk, prevention, symptoms, monitoring yourself and coworkers, treatment, and PPE.
- Engineering controls: radiant heaters at outdoor work stations, and shielding the work area from the wind to cut wind chill.
- Scheduling: heavy work in the warmer part of the day, and cold jobs in the warmer months where there is a choice; relief workers or extra workers on long cold jobs; limited time outside on extremely cold days.
- Warm breaks: frequent short breaks in a warm, dry area, and warm, sweetened, non-alcoholic drinks.
- A buddy system so workers watch each other, and supervisors who monitor workers at risk.
- Acclimatize new and returning workers gradually, the same as for heat.
- Protective clothing, which NIOSH says the employer should cover in training and OSHA describes layer by layer in the next section.
What does OSHA say to wear?
At least three loose layers; tight clothing restricts circulation and compresses insulation. The inner layer is wool, silk or synthetic to wick moisture away from the skin, not cotton, which holds sweat. The middle layer is wool or synthetic for insulation that keeps working when wet. The outer layer blocks wind and rain and still lets some moisture out. A hat or hood, because a hat reduces the heat lost from the head. Insulated gloves, water-resistant where the work is wet. Insulated, waterproof boots. NIOSH adds the things to carry: extra socks, gloves, a hat and a jacket, blankets, and a thermometer and chemical hot packs in the first aid kit, and warns against touching cold metal with bare skin.
OSHA Cold Stress Guide, protective clothing (three loose layers; inner wicking layer; middle insulating layer; outer wind and rain layer; hat or hood; insulated gloves; insulated waterproof boots); NIOSH, Cold Stress: Cold and Work, recommendations for workers.For gloves, the only published cold rating is EN 511, three digits for cold air, cold surfaces and water. A glove for handling frozen product or cold steel needs the second digit; a glove for standing in wind needs the first; wet work needs a 1 in the third place or the other two do not last past the first soaking. The band below shows the manufacturer’s EN 511 code where one is published. A hard hat winter liner replaces the hat OSHA calls for under a hard hat, which cannot take a hat under its suspension.
EN 511:2006 as published by the glove manufacturers in the band.Who pays for winter gear?
OSHA’s PPE payment rule requires the employer to pay for required PPE, with named exceptions, and one of the exceptions is ordinary clothing, skin creams, or other items used solely for protection from weather, such as winter coats, jackets, gloves, parkas, rubber boots, hats, raincoats, ordinary sunglasses and sunscreen. So an employer may require a crew to dress for the cold without buying the coats. The line moves when the item is PPE for a hazard other than weather: insulated gloves with a cut rating for handling sheet metal in winter, FR-rated winter liners for an arc flash program, or chemical-resistant insulated gloves are PPE selected under the hazard assessment and are paid for by the employer. Many employers supply winter gear anyway, because a crew that owns good gloves keeps working.
29 CFR 1910.132(h)(1) and (h)(4); 1910.132(d)(1) hazard assessment for PPE that protects against a non-weather hazard.Insulated gloves, hard hat liners and warmers
38 items · prices liveEN 511 cold ratings, lining and coating are as published by each manufacturer. Where a glove has no published EN 511 code, the manufacturer’s coating is shown instead. Hard hat liners and warmers are described as the maker labels them. Free shipping on orders over $199.
All 140 cold-weather gloves we carry, rated and unrated, are on the work glove selector. Winter jackets and bodywarmers are in the hi-vis and cold weather wear categories.
Questions people ask
What is cold stress?
The body losing heat faster than it can produce it, so skin and then core temperature fall. The injuries are frostbite, trench foot and hypothermia.
Does OSHA have a cold weather standard?
No. OSHA says there is no specific cold-environment standard; employers must protect workers from cold stress as a recognized hazard under section 5(a)(1) of the OSH Act, and OSHA publishes its Cold Stress Guide on how.
At what temperature does cold stress start?
There is no fixed number. OSHA notes that in regions not used to winter, near-freezing temperatures count as extreme cold, that hypothermia can occur above 40°F in a worker wet from rain or sweat, and that trench foot can occur at 60°F with constantly wet feet.
What is wind chill?
The temperature the body feels when air temperature and wind speed are combined. Wind strips heat from exposed skin faster, so the same thermometer reading is more dangerous on a windy day.
What are the first signs of hypothermia?
Shivering and stomping the feet while still alert. When shivering stops and the worker becomes clumsy, confused or disoriented, it is severe; call 911.
Should you rub frostbite?
No. OSHA says rubbing causes more damage, and not to apply snow or water, break blisters, or rewarm the area before medical help; cover it loosely and get the worker to care.
How should workers dress for the cold?
OSHA: at least three loose layers, a wicking inner layer, an insulating middle layer that works wet, a wind- and rain-blocking outer layer, a hat or hood, insulated gloves and insulated waterproof boots.
Does the employer have to pay for winter gloves and coats?
Not for ordinary weather clothing; 1910.132(h)(4) exempts winter coats, gloves, boots and hats worn only for weather. Gloves selected for a non-weather hazard, such as cut-rated insulated gloves, are PPE the employer pays for.
What do the EN 511 numbers on a winter glove mean?
Convective cold 0 to 4, contact cold 0 to 4, water penetration 0 or 1, in that order; X means not tested. The full scale is in our cold-weather gloves guide.
Standards and ratings on this page are as published in the documents named and by the manufacturers named. The employer’s hazard assessment and written program decide what applies at a given workplace. Verify a rating on the product and its spec sheet before use.