Keeping Employees Safe from Extreme Temperatures in the Workplace

A cool breeze that pleases one person sends chills through another. While some people bask in the sun’s rays, others scramble to get out of the heat. Temperature preferences are definitely personal.

In the workplace, employees usually find ways to adjust to temperature preferences, such as putting on a sweater to keep warm or taking off a jacket to cool down. But extreme temperatures — near thermometer-busting heat and Arctic air deep freezes — are life-threatening conditions.

Extreme temperatures jeopardize employees’ health and on-the-job performance.

What studies show about the effects of temperatures on workers

How serious are temperature differences in the workplace? Among employees’ top 10 office complaints, disagreements about temperature topped the list in a 2003 poll of members of the International Facility Management Association (IFMA). Claims of “it’s too cold” came in 1st place, followed by complaints of “it’s too hot.”

In multiple simulated studies on how temperatures affect people’s indoor activity, analysts found that productivity peaked at 71 degrees but declined as temperatures ticked up or fell below the peak level.

These studies show that temperatures don’t have to be extreme to have a negative impact on how people function indoors. Even moderate temperature fluctuations in a work environment can make employees less productive.

But extreme temperatures not only cause employees to be annoyed, uncomfortable, and irritable; they can cause severe health conditions, like heat stress and hypothermia. They can also trigger action from the federal Occupational Safety and Health Administration (OSHA) under the U.S. Department of Labor (DOL).

OSHA’s role in workplace temperature control

Employers must disregard personal preferences when temperatures become excessively hot or cold, because that’s when OSHA and similar state agencies step in with regulations.

The agency recognizes that workers have temperature preferences and intolerances, so, it recommends that employers set workplace thermostats at between 68 and 78 degrees. But OSHA regulations will kick in to protect workers from health-threatening temperature extremes.

OSHA uses heat stress meters to measure a workplace’s temperature and humidity levels. The agency identifies these sources of heat stress risks for workers:

• The environment, such as sunlight, air temperature, humidity, and air speed.
• Ovens, furnaces, and other heat generators in work areas.
• Physical activity levels, such as body heat production or workloads.
• Workers’ personal risk factors.

Employers can’t afford to wait until workers start coming down with temperature-related illnesses. They can be proactive about protecting workers by knowing how to meet OSHA standards and understanding how excessive heat and cold affect the body.

What are the dangers of heat stress for workers?

The American Conference of Government Industrial Hygienists defines “heat stress” as “the total net heat load on the body,” or the amount of heat an external source like an oven or furnace has on the body.

The body rids itself of excess heat through perspiration or increased blood flow to the skin. When the body can’t cool itself down quickly enough, its internal temperature rises, causing the victim to experience heat stress or diminished mental and motor skills.

Heat stress symptoms include:

• High temperature
• Sweating
• Dry, hot skin
• Hallucinations
• Dizziness
• Confusion

A body temperature of 100 degrees Fahrenheit means trouble for an employee’s health.

What are the dangers of cold stress for workers?

The body uses extra energy to maintain the right temperature. Under extremely cold conditions, blood flows from the extremities like the feet, hands, and outer skin to the body’s center or core.

When the body’s temperature drops below the normal level of 98.6 degrees F to below 95 degrees F, a dangerous health condition is possible. Excessive cold puts workers at risk for hypothermia, frostbite, and trenchfoot.

Cold stress symptoms include:

• Fatigue
• Shivering
• Dilated pupils
• Coordination loss
• Blue-tinged skin

Employers must remember that heat and cold stress can cause death. That’s why preventing extreme temperatures in the workplace, immediate medical intervention for victims, and compliance with OSHA regulations are critical.

What can employers do to mitigate these effects?

Since excessive heat has serious health risks, here are basic things you can do based on OSHA recommendations to protect workers in hot weather.

Preventing heat stress

• Keep work areas well-ventilated. Turn on air conditioners or fans, if possible.
• Have plenty amounts of drinking liquid on hand and near workstations so that employees can stay hydrated. Encourage them to drink small amounts of liquid several times throughout the day to replenish the water their bodies lose through perspiration.
• Transfer employees to cooler work areas where they’re likely to be more comfortable performing their jobs.
• Allow employees to take frequent rest breaks throughout the day to avoid becoming overwhelmed by the heat.
• Establish cool resting places in nonworking areas where employees can escape the heat and become re-energized before resuming their work.
• Relax your company’s dress code, if and whenever possible. Encourage employees to wear light-colored, lightweight, loose-fitting clothing, which absorbs less heat than dark-colored, close-fitting garments.
• Consider changing your company’s work hours. Organizations with multiple shifts can try starting the first shift earlier and the second shift later to avoid the hottest hours of the day.

Keeping workplaces well-ventilated also minimizes the spread of airborne viruses and other contaminants.

Keeping workplaces well-ventilated also minimizes the spread of airborne viruses and other contaminants.

Employers in the construction, mining or warehousing industries also must protect their employees, who may work offsite or in confined areas under extremely hot or cold conditions.

Preventing cold stress

OSHA recommends training employees on how to recognize hazards on the job and to know what safety practices to follow. This applies to preventing both heat and cold stress.

The strategies employers can use to prevent cold stress include:

• Provide workers with heat-generating equipment, such as radiant heaters, and set up wind and draft barriers at the worksite to protect workers from drafts.
• Have plenty of warm liquids for employees to consume to prevent dehydration, a common health problem in cold weather.
• Assign workers to perform tasks in pairs, when possible, so they can monitor each other for signs of cold stress.
• Allow workers to take breaks and retreat to warmer areas of the worksite if they feel chilled and uncomfortable.
• Encourage employees to wear clothes that protect them from the cold, such as garments made of synthetics, wool, and silk (not cotton because it loses its insulation when wet)
• 3 layers of loose-fitting clothing
• A hat or hood to keep body temperatures normal
• Gloves, preferably water-resistant
• Insulated and waterproof shoes or boots

More on ventilation in workplaces for good health

Besides setting outdoor health and safety standards, the U.S. Environmental Protection Agency (EPA) also provides building owners and operators with guidance on maintaining healthful indoor air quality.

The guidance coincides with OSHA’s stand on keeping workplaces well-ventilated to minimize health problems, including heat-induced illnesses.

The EPA has a set of guidelines and best practices called the “Clean Air in Buildings Challenge” to reduce the health risks of airborne viruses and other indoor contaminants. The agency wants to protect building occupants, which naturally include workers, and help slow the spread of COVID-19.

Actions outlined in the “Clean Air in Buildings Challenge” include:

• Creating a clean indoor action plan.
• Optimizing fresh air ventilation.
• Improving air filtration and cleaning.
• Engaging, communicating, and educating the community about maintaining clean indoor air.

Why weather reports are unreliable for worksite temperatures

OSHA warns employers against relying on weather reports to forecast worksite temperatures. According to the agency, meteorology is unreliable because it:

• Gauges only outdoor, not indoor temperatures.
• Only measures temperature and heat indices in shady areas and not in direct daylight, where temperatures can be much higher.
• Can’t account for heat caused by fires, ovens, hot equipment, or heat-generated surfaces such as roads or rooftops.
• Cannot accurately measure worksite temperatures affected by windy conditions.
• Can’t measure temperatures from reflective materials like metal or water.

Employers should draft policies on temperature safety

How can employers know when temperatures are at dangerous levels? Waiting until employees show symptoms is too late.

OSHA recommends using wet bulb globe temperature (WBGT) monitors to measure environmental heat in the workplace.

Employers can find OSHA’s standards on controlling extreme heat and cold temperatures in the workplace on the agency’s website.

For emergency first aid information, employers can refer to OSHA’s Medical Services and First Aid standard and the Medical Services and First Aid in Construction standard.

Finally, employers should draft policies on temperature safety in the workplace and what actions to take if workers experience heat or cold stress.