Indoor Heat Stress: How to Protect Workers in Offices and Indoor Environments
The Hidden Dangers of Heat Stress Indoors
Heat stress indoors is a significant occupational risk, particularly in environments with extremely high temperatures. When we envision heat stress, many will picture outdoor workers in the summer heat, but there are many industries where workers are subjected to sweltering conditions indoors. For example, manufacturing facilities, warehouses, kitchens, bakeries, and mines are at-risk industries for indoor heat stress.
Workers in these industries can be exposed to heat stress indoors due to a variety of factors, and the symptoms of heat stress can range from mild fatigue and headaches to severe confusion, seizures, and even death. The Occupational Health & Safety Act requires employers to take every reasonable precaution to protect workers. In this blog, we’ll explore effective strategies to prevent heat stress indoors and ensure a safer work environment.
Causes of Indoor Heat Stress
When workers experience heat stress indoors, there are many potential causes, such as:
Environmental factors: Environmental factors such as ambient air temperature, air movement, and relative humidity can all contribute to heat stress indoors.
Radiant Heat: Radiation is heat transfer from hot objects through air to the body. Working around heat sources such as kilns or furnaces will increase heat stress.
Humidity: Humidity is the amount of moisture in the air. Heat loss by evaporation is hindered by high humidity but helped by low humidity. As humidity rises, sweat tends to evaporate less. As a result, body cooling decreases and body temperature increases.​
​Air Movement: Air movement affects heat exchange between the body and the environment.
The Effects of Indoor Heat Stress on Workers
Heat stress indoors can have both physical and mental effects on workers. The effects can range from acute to chronic depending on time exposure, individual physiology, and more.
​Acute health effects of heat stress include:
- Heat rash is common in warm/moist conditions. It happens when the sweat glands become blocked, obstructing the normal sweating process and causing swelling and irritation of the skin. ​
- Heat cramps are muscle cramps that come from prolonged exposure to excess heat. The body loses so much fluid in the form of sweat that it cannot replace the salt lost with the sweat.​
- Heat exhaustion is the result of continuous exertion in heat, accompanied by dehydration from deficient water and salt intake.
- Chronic heat illness is the result of long-term exposure to work in hot environments. Heat exposure can cause chronic damage to the digestive, central nervous, and immune systems.
Strategies for Preventing Indoor Heat Stress
Heat stress indoors can be controlled through engineering, education, and work procedures. We recommend controlling heat exposure in the following ways:
- At the source: This control would entail lowering the temperature of radiant heat emitted by the process. This result is achieved either by process changes or by isolating the source with insulating or reflective materials
- Along the path: This control would entail controlling workplace temperature and humidity. This can be achieved by improving ventilation and implementing cooling systems, such as air conditioning or fans.
- At the worker: Controls applied at the worker are a last resort and are the least satisfactory because they fail to change the surrounding environment. These controls consist of administrative practices and policies, such as work-rest scheduling. Lastly, we consider personal protective equipment.
Heat stress indoors poses a significant threat to workers in various industries, including manufacturing, warehousing, and food service. By understanding the causes, effects, and strategies for prevention, employers can take steps to protect their workers from the dangers of heat stress.
HSPI offers Workplace Hazard Assessments that can identify heat stress hazards in your workplace. Collaborating closely with employers, we tailor a suitable solution for your workplace. To learn more about our Workplace Hazard Assessment services, please visit our website.
