Cold stress at work: spot it early, plan for it

What is cold stress at work?

Cold stress is the strain on the body when it loses heat faster than it can make it. NIOSH says that when temperatures drop below normal, heat can rapidly leave your body. Cold, wind and wet clothing all speed that loss. The result can be a cold-related illness.

NIOSH lists outdoor workers, workers in poorly insulated or unheated areas, and workers in areas without shelter as people who may be at risk. That covers concrete crews on a January pour, roofers, utility crews, loaders on an open dock and warehouse teams in unheated buildings.

Cold stress also depends on place. NIOSH says what counts as cold stress varies across the country. In regions unaccustomed to winter weather, near freezing temperatures are considered factors for cold stress. A Texas crew can get hurt at temperatures a northern crew would call mild. See cold stress in the glossary.

What are the four cold-related illnesses?

NIOSH names four: hypothermia, frostbite, trench foot and chilblains. Hypothermia is a drop in core body temperature. Frostbite is freezing of skin and the tissue under it. Trench foot comes from long contact with wet, cold conditions. Chilblains are painful skin reactions to cold.

The table below is a field card for supervisors. It gives plain meanings and a site action. It is not a diagnosis. Ask your site medical provider to add symptom detail and first aid steps for your crew.

When a worker looks confused, cannot stop shaking or cannot work normally, treat it as urgent and call 911.

How can employers reduce cold stress risk?

Employers cut cold stress by changing the work and the setting before the cold arrives. NIOSH steps include scheduling cold jobs for warmer times, using relief workers, providing warm liquids and warm break areas, limiting time outside, monitoring at-risk workers and training.

Here is the NIOSH employer list, turned into a plan you can post:

1. Schedule cold jobs for warmer months or the warmer part of the day.
2. Use relief workers or assign extra workers for long jobs.
3. Provide warm liquids to workers.
4. Provide warm areas for use during breaks.
5. Limit the amount of time outside on extremely cold days.
6. Monitor workers who are at risk of cold stress.
7. Provide cold stress training.

Put numbers on step 5 for your site. Set a warm-up break length and a trigger, such as a forecast low or wind speed, that starts it. Write the trigger down in your heat illness prevention plan or winter plan so every foreman applies it the same way.

What should workers wear and carry?

Workers should dress in layers, protect ears, face, hands and feet, and carry spares. NIOSH advises several layers of loose clothing for better insulation, waterproof and insulated boots, and a hat. Some clothing can restrict movement, which can be dangerous around equipment.

Add these items to the truck or the cart:

• Extra socks, gloves, a hat, a jacket and blankets, as NIOSH suggests
• A thermometer and chemical hot packs in the first aid kit
• A rule to avoid touching cold metal surfaces with bare skin
• A buddy system so each worker watches one other worker

Wet is worse than cold. Dry socks matter on a rainy day more than a thicker jacket does.

Do crews still need to hydrate in the cold?

Yes. Cold work still uses water, and people tend to drink less when they are not hot. JMAR’s winter hydration post says cold weather decreases the thirst sensation, so it is important to have systems that encourage drinking. It also says chilly dry air raises the water vapor we lose by breathing.

Treat those as JMAR’s statements. They match a common field problem: nobody feels thirsty in a parka. Build drinking into the day instead of waiting for thirst.

• Put a marked water bottle in each crew member’s hand at the start of the shift.
• Pair every warm-up break with a drink break.
• Offer warm liquids, as NIOSH recommends.
• Check that water stations do not freeze.

JMAR’s post also suggests adding concentrated electrolytes to daily water. Rapid Restoration Drops are a dietary supplement that replace electrolytes lost in sweat and support hydration. Read the winter hydration post for JMAR’s full text. Cold stress illnesses need warming and medical care, not a supplement. For the basics of hydration and electrolytes, see our other guides.

What should a cold stress talk cover?

NIOSH says cold stress training should cover worker risk, prevention, symptoms, monitoring yourself and coworkers, treatment and personal protective equipment. Keep the talk short and local. Name your warm-up shelter, who holds the spare gloves, and who calls 911.

Run it as a five-minute toolbox talk before the first cold snap. Our heat toolbox talk script uses the same format. Swap the heat signs for the cold signs in the table above.

Is there an OSHA rule for cold stress?

We did not find a standalone federal OSHA cold stress standard on the pages we reviewed. NIOSH links to OSHA’s Cold Stress Guide and Winter Weather resources. OSHA’s General Duty Clause covers recognized hazards in general. This guide is not legal advice.

For heat, see OSHA heat rules. Talk to your safety professional or OSHA’s free On-Site Consultation program about winter planning.

How does the plan change by site type?

The risk and the fix differ for an open pour, a loading dock and an unheated warehouse. Start from the NIOSH employer list, then match each step to the place. The table shows one way to do it. Adjust it with your safety team and your site’s medical provider.

NIOSH names workers in poorly insulated or unheated areas and workers in areas without shelter as people who may be at risk. A warehouse crew is not safe just because the roof is on.

What mistakes do crews make in cold weather?

Most mistakes come from treating cold as a comfort issue. Four show up often. Each has a simple fix drawn from the NIOSH list.

• Waiting for the worker to speak up. Workers may not speak up. Use a buddy system and a foreman check instead of relying on self-reports.
• No place to warm up. A truck cab with one seat is not a plan. NIOSH tells employers to provide warm areas for use during breaks.
• Too many tight layers. NIOSH says to wear several layers of loose clothing for better insulation. It also notes that some clothing may restrict movement, which could be dangerous around moving equipment.
• Wet gear. Carry spare socks, gloves, a hat and a jacket, as NIOSH suggests.

Put one line from this list into each morning briefing. Rotate the line each week so crews do not tune out.

What should a winter checklist include?

A winter checklist turns the plan into a daily habit. Foremen run it in two minutes before work starts. Keep it on the same sheet as your heat checklist so the habit carries across seasons.

1. Forecast checked, including wind and wet conditions.
2. Warm break area open, stocked and reachable.
3. Warm liquids available.
4. Spare socks, gloves, hats and jackets on hand.
5. First aid kit includes a thermometer and chemical hot packs.
6. Relief workers assigned for long jobs.
7. At-risk workers named and being watched.
8. 911 caller named for the shift.

Review the sheet weekly. If a line is blank three days in a row, fix the cause, not the paperwork.

Next step

Want a winter hydration plan and a toolbox talk for your crew? Book a 15-minute demo or ask for a free sample. See also heat stress prevention and our hydration programs.