Dashpivot Article – Heat Stress Hazards and Control Measures

Heat Stress Hazards and Control Measures

Heat Stress Hazards and Control Measures: Why Are They Important to Know?

Heat stress happens when your body can't keep itself cool enough. It's a problem in many jobs throughout the year, but it's even more of a risk during summer, particularly for those working outside.

Both indoor and outdoor workers can suffer from heat exposure. The effects of heat stress range from mild symptoms like intense thirst and fatigue to severe outcomes such as death if proper safety measures aren't taken.

How does your body react to too much heat?

The impact of heat stress shouldn't be underestimated. It can escalate to heatstroke, a critical condition where body temperature soars above 104°F. Warning signs include confusion, fainting, seizures, and can lead to death in extreme cases.

To manage and mitigate these risks, understanding how to recognise and respond to the signs of heat stress is crucial. Read on to learn about heat stress hazards and control measures to ensure a safe working environment for your workers.

Why Are Construction Workers at a Higher Risk of Heat Stress?

The physically demanding nature of their work means construction workers are constantly generating more heat within their bodies. Whether it's lifting heavy materials, using heavy machinery, or just moving around a lot, these activities all contribute to increased internal heat.

Moreover, being outdoors often puts construction workers directly in the path of the sun's rays. This not only raises the surrounding air temperature but also increases their risk of getting sunburnt and developing skin cancer over time.

Finally, the safety gear that construction workers must wear can actually make it harder for their bodies to cool down. Hard hats, heavy-duty boots, gloves, and protective clothing are all critical for safety, but they can also trap heat and reduce the effectiveness of sweating, leading to overheating.

Common Heat Stress Hazards

Environmental Heat

Environmental heat comes from the warm or hot conditions surrounding a work area.

There are four main elements that contribute to heat stress among workers:

Air Temperature: The basic measure of how hot the surroundings are.
Humidity: When humidity is high, sweat doesn't evaporate as efficiently, making it harder for the body to cool itself.
Radiant Heat: This can come from direct sunlight or from artificial sources like furnaces, increasing the heat workers are exposed to.
Air Movement: Generally, a breeze or wind can help cool down workers by promoting sweat evaporation.

To accurately assess environmental heat risks, it's recommended to use a Wet Bulb Globe Temperature (WBGT) monitor. This tool is preferred because it considers all these factors together, unlike standard thermometers, which only measure air temperature.

Metabolic Heat

Another source of heat stress is metabolic heat, which is the body's internal heat generated during physical activities.

This type of heat is most concerning for those doing hard physical work. As the intensity of the work increases, so does the amount of heat the body produces. This internal heat, when added to environmental heat, can push the body's core temperature to unsafe levels.

To manage this risk, it's important for employers to understand the intensity of the work being performed, categorised as light, moderate, heavy, or very heavy:

Light: Tasks that involve sitting or standing with little movement.
Moderate: Activities that require continuous but moderate effort, such as walking at a normal pace.
Heavy: Demanding tasks involving upper body effort, like carrying heavy loads.
Very Heavy: Extremely intense activities performed at near maximum effort.

Tasks classified as heavy and very heavy pose the greatest risk for heat-related illnesses.

Convective Heat

Convective heat comes from the movement of hot air or liquid around objects. Workers in environments like foundries, boiler rooms, and other areas exposed to hot liquids (such as molten metal), steam, or hot gases face a significant risk from convective heat.

Why is Convective Heat a Concern?

Equipment and Machine Safety: Heated fluids and gases expand, posing a risk in industrial environments with machinery. Overheated parts can expand, leading to malfunctions or breakdowns.
Fire Hazards: Hot fluids or gases can easily ignite, causing fires to spread rapidly through the air due to convection. This highlights the importance of fire safety in industrial settings.
Damage to Materials: Heat-sensitive items can warp or get damaged by the temperature changes brought on by convective heat. This can affect everything from electronics and books to food items.
Worker Health and Productivity: Hot air makes it difficult for employees to work comfortably. It can lead to increased body temperature, difficulty breathing, and symptoms like dizziness. Over time, this exposure can result in serious health issues such as dehydration, heat exhaustion, or heat stroke.
Equipment Damage: Fans circulating hot air can overheat electronic components, leading to malfunctions or permanent damage, potentially requiring costly replacements.

Control Measures to Prevent Heat Stress

Engineering Controls

Adding Insulation: Adding insulation helps keep work areas cooler by blocking heat from coming in. This could mean insulating walls, roofs, floors, pipes, and equipment.
Create Shade: For outdoor work areas, shade is crucial. Use umbrellas, canopies, or other structures to shield workers from the sun and lower heat exposure.
Provide Cool Water: Access to cool drinking water is essential, as are misting stations or showers for a quick cooldown. Encourage regular water breaks to stay hydrated.
Limit Sun Exposure: Try to minimise time spent in the heat or direct sunlight by adjusting work hours to cooler times or setting up work breaks in shaded or air-conditioned areas.
Adjust the Workload: Heavy work increases heat stress. Lighten the workload during hot conditions, or bring in extra help to share the load. Employ automation and machinery for heavy tasks.
Use of Shields: Install shields to block radiant heat from reaching work areas. Reflective shields made from materials like stainless steel or aluminium redirect heat, while absorbent shields, such as water-cooled jackets, can absorb and remove heat.

Administrative Controls

Work Together: Using a buddy system means workers can look out for one another for signs of heat stress. Sharing tasks also prevents overworking.
Rethink Uniforms: Opt for work clothes that are breathable and light, which can help keep body temperatures down.
Acclimatise Workers: Gradually get workers used to hot conditions to reduce the risk of heat-related illnesses.
Take Regular Breaks: Encourage breaks in cool or shaded areas, especially during the hottest parts of the day, to prevent overheating.
Educate Your Team: Training on recognising heat stress symptoms and prevention methods is crucial. Encourage speaking up if symptoms arise or if someone notices a colleague struggling.
Incorporating Toolbox Talks: Scheduling toolbox talks regularly to keep the team updated on the latest safety guidelines, highlight high-risk situations, and share any recent changes in the job site or work conditions since the team's last shift. By actively engaging in these discussions, your workforce stays informed and prepared, ensuring a safer work environment for everyone.

Personal Protective Equipment (PPE)

Lightweight Clothing: In humid and hot workspaces, wearing lightweight clothing improves the body's natural cooling process through sweat evaporation.
Cooling Vests: These vests have pockets for ice packs or built-in cooling systems to help keep body temperatures in check.
Cooling Bandanas/Neck Wraps: Worn around the neck, these help cool down blood flowing to the brain.
Eye Protection: When working near extremely hot objects, eye protection that blocks radiant heat is essential to prevent damage.
Other Cooling Gear: Cooling helmets, hats, and arm sleeves can also help lower the risk of heat stress.

Tips for Preventing Heat-Related Illnesses in the Workplace

Limit Time in Hot Conditions

Adjust work schedules so that the most physically demanding tasks are performed during the cooler parts of the day.

Improve Air Flow

Utilise fans, air conditioning, and ventilation systems to reduce indoor temperatures, and install structures that provide shade or shield workers from direct heat.

Keep an Eye on Worker Health

Regularly check on employees who are more vulnerable to heat stress, whether due to the nature of their work, health conditions, or certain medications.

Salt and Water Balance

Workers in very hot environments lose both water and salt through sweat. It's important to balance this loss by consuming adequate amounts of water and salt. The goal is to match fluid intake with fluid loss.

Emergency Preparedness

Have an emergency action plan ready for severe conditions. This plan should outline steps for offering first aid and obtaining medical assistance for affected employees.

Importance of Heat Stress Hazards and Control Measures Training and Awareness

Every construction firm must prioritise a heat illness prevention program within its safety strategy. This program is essential for educating workers on the critical aspects of heat stress, including identifying the warning signs in themselves and their colleagues, and knowing what to do if an emergency arises.

It's vital for employees to be fully aware of the heat stress risks associated with their roles and to be able to recognise the symptoms early on.

In the construction sector, where the risks are notably high, imparting knowledge on health and safety through formal training is indispensable. This includes hands-on sessions that address the specific equipment and hazards found in the workplace, complemented by additional training for broader awareness, such as online health and safety courses.

Moreover, reinforcing formal training with regular toolbox talks proves to be highly effective in solidifying understanding and fostering a strong culture of safety.

Toolbox talks provide brief yet impactful discussions or presentations on specific health and safety issues, aimed at refreshing workers' knowledge. They serve as an excellent way to begin the work day, ensuring that safety is the primary focus for all.

Check out our sample heat stress toolbox talk template below.

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Integrating Toolbox Talks into Heat Stress Prevention Strategies

It's important for workers to be well-informed about the hazards associated with heat stress and the measures employees can take to protect themselves. Recognising the dangers associated with heat stress and actively working to prevent it are key components of maintaining a safe workplace.

Holding regular safety meetings and toolbox talks is an effective strategy to foster a culture of safety within your organisation and reinforces your company's commitment to worker protection. These sessions help prevent complacency among workers and ensure that they never take safety for granted.

Our free heat stress toolbox talk template is designed to make it easier to plan and conduct toolbox talks, and comes prebuilt with sections for outlining the risks of heat stress, sharing personal experiences from the team, discussing prevention strategies, recognising symptoms, and much more.