OSHA Indoor Temperature Regulations: What Warehouse Operators Should Know


The Occupational Safety and Health Administration (OSHA) is undertaking a proposed rulemaking process that may lead to new standards for workplace heat stress.

In 2021, OSHA published an Advance Notice of Proposed Rulemaking (ANPRM) for Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings. An ANPRM allows OSHA to gather information, perspectives, and comments from the public, which the administration may use to establish obligations for employers.

Currently, OSHA publishes non-binding guidance for working in hot environments, and employers have obvious incentives to keep their workers safe. Workplaces with unsafe conditions may face fines and other penalties under the General Duty clause (section 5(a)(1) of the Occupational Safety and Health Act of 1970).

It’s likely that any new standards will be aligned with existing state OSH standards in states like Minnesota, California, and Washington — and by reviewing those regulations and OSHA’s non-binding guidance, employers can prepare for any new rules.

OSHA State Plans and Temperature Regulations

Several states have OSHA-approved State Plans that establish temperature regulations for warehouses, factories, construction projects, and other work environments.

If (and when) OSHA publishes national standards for heat regulation, it’s likely that those standards will mirror some aspects of the State Plans. However, those plans address very different hazards:

  • Minnesota - MNOSHA’s standard applies to indoor workplaces and establishes permissible heat exposure limits of 77 degrees Fahrenheit for two hours of heavy work, as measured by wet bulb temperature index (WBGT). Read the full regulation for additional details.
  • California - CalOSHA’s standard establishes requirements for employers when temperatures reach or exceed 80°F. Employers must generally provide training, hydration, shade, and have a documented planning process. Read CalOSHA’s website for additional details.
  • Washington - Washington’s regulations only apply when employees are exposed to outdoor heat above certain temperatures. Employers must encourage employees to hydrate frequently and establish outdoor heat exposure safety programs within their written accident prevention program (APP). Read the full regulation for additional details.
  • Oregon - Oregon OSHA applies to both outdoor and indoor environments. It establishes requirements for monitoring employees, measuring temperatures, and implementing heat illness prevention rest break schedules. Read the full regulation for additional details.

The common thread: Employers must generally measure temperatures, control hazards, and establish breaks for employees. Workers must have access to potable water, and employers must have acclimation procedures for new workers.

For warehouses, these aren’t new concepts — successful warehouses already meet most of the requirements of state OSHA standards.

But controlling hazards remains an important priority. That process begins with understanding the potential dangers of heat exposure.

How Much Heat is Dangerous to Workers?

Setting outdoor and indoor temperature regulations isn’t straightforward. While ambient temperatures are an important factor, other factors like ventilation, clothing, and personal protective equipment (PPE) play a role in determining whether an environment is safe or unsafe.

Additionally, healthy workers who have experience performing heavy tasks in hot environments will generally acclimate to the work. The National Institute for Occupational Safety and Health (NIOSH) notes other factors:

  • The tools used to handle work. Ergonomic equipment can reduce the intensity of the workload, potentially enabling workers to work safely for longer periods in high-heat environments.
  • The age of the worker. Older workers (aged 65 and up) are more likely to experience the most dangerous effects of heat exposure.
  • The use of heat-protective clothing.
  • The use of many medications, including antidepressants, antihistamines, barbiturates, and narcotics.

OSHA and NIOSH provide a useful Heat Safety Tool, which provides a visual indicator of current heat risks based on the user’s geographic location.

Because workloads and environmental controls vary greatly from industry to industry, OSHA’s future heat safety regulations will likely focus on things that employers can control — providing cool, potable water, monitoring employees for signs of heat stress, requiring adequate rest breaks, and establishing acclimation periods for new workers.

New and Temporary Workers Should Be Exposed to Heat Gradually

As OSHA notes, almost half of heat-related deaths occur on a worker’s first day on the job, and over 70 percent of heat-related deaths occur during a worker’s first week.

Heat acclimation — the body’s process of adapting to elevated heat — takes time. As workers spend more time in hot environments, they become more tolerant to the conditions.

That doesn’t mean that seasoned workers can work in extreme temperatures for long periods of time without breaks. However, OSHA recommends strategies to establish a “culture of acclimatization" and reduce risks for new and temporary workers.

New workers should work shorter days for their first 1-2 weeks. OSHA and NIOSH recommend the “Rule of 20%” for building tolerance:

  • On the first day, new workers should only work 20% of the normal duration.
  • Work duration may be increased by 20% on subsequent days until the worker is performing a normal workday.

New and temporary workers should perform tasks that are “similar in intensity to their expected work.” For example, if a worker will spend most of their time packing boxes in a hot warehouse, they should perform packing tasks from day one — but for 20% of their eventual workday.

Providing new workers with lighter workloads may not help them acclimate to the heat. In other words: Reduce the duration of the work, not the intensity.

Know the Signs of Work Heat-Related Illness

OSHA and NIOSH also recommend monitoring all employees — but especially new and temporary employees — for signs of heat stress.

At the early stages, those symptoms may include:

  • Muscle pain or spasms.
  • Heavy sweating.
  • Cold, pale, and/or clammy skin.
  • A fast, weak pulse.
  • Nausea or weakness.
  • Dizziness or headache.

Workers who display these symptoms should move to a cool place immediately, sip water, and rest before performing any other physical activities.

Severe heat exhaustion can lead to additional symptoms, which require medical help and appropriate reporting for on-the-job injuries:

  • Fainting (losing consciousness).
  • Vomiting.
  • A body temperature of 103 degrees Fahrenheit or higher.
  • Fast, strong pulse.
  • Confusion.

Employers should monitor for these signs, but should also provide employees with training materials that explain the dangers of heat exhaustion and heat stroke. Employees should monitor themselves and their coworkers and inform management as soon as heat becomes an issue.

The Centers for Disease Control and Prevention (CDC) provides a printable “Heat-Related Illnesses” poster in English and Spanish, which may be useful for training.

Current OSHA Standards Establish Some Requirements for Handling Indoor and Outdoor Heat Hazards

OSHA doesn’t currently have specific standards regulating temperatures (although again, the General Duty clause covers situations in which workplace temperatures pose an obvious threat to workers).

With that said, several standards may apply to workplaces with routinely hot or cold ambient temperatures:

Taking Steps to Protect Workers by Limiting Heat Stress

Of course, employers don’t want to expose their workers to heat stress — and while OSHA/NIOSH standards may change, the simple fact is that successful businesses protect their employees.

In addition to heat acclimation for new workers, employers can take immediate steps to control heat hazards while improving productivity:

  • Invest in ergonomic material handling equipment. Eliminating heavy tasks will reduce heat hazards. Products like scissor lift tables, tilt tables, and bin dumpers can remove manual tasks from the workflow while enhancing throughput.
  • Assign more workers to heavy tasks. This enables workers to take appropriate breaks and further reduces the effort (and sweat) required for each job.
  • Establish a safety-first culture. Train employees to know the signs of heat-related illnesses and to monitor themselves — and their coworkers — for those symptoms.
  • Enforce water breaks. Make sure water is cool (59 degrees Fahrenheit) and plentiful.

Beat the Heat with Ergonomic Equipment from BHS

As is the case with many on-the-job hazards, appropriate equipment is key — and may be the easiest improvement to put in place.

By focusing on ergonomics, BHS helps employers comply with OSHA standards — and prepare for future standards — while reducing unnecessary work and improving productivity. Contact BHS at 1.800.247.9500 to discuss options for your business.