Heat stress is a major risk to health and safety on a worksite. But if allowed to get out of hand, its consequences can also prove dire.
Those in construction, manufacturing and mining are among those most at risk of heat stress while at work. This is because they deal with high ambient temperatures and humidity, often work in poorly ventilated areas and use heat producing tools and machinery. These employees also work close to heat storing materials such as concrete, rock and metal and often require substantial protective clothing and equipment.
Fortunately, death from occupational heat stress is relatively uncommon in Australia, with the National Coronial Information System recording 17 cases of work-related heat stress deaths between 2000 and 2015. However, heat stress can also significantly reduce people’s capacity to work. A recent KPMG report showed that by 2030, two per cent of total working hours worldwide will be lost every year as high heat makes working more difficult.
In Australia, there is not a specific temperature at which action must be taken by an employer, but an employer’s duty of care means that people carrying out work in extreme heat must be able to do so without risks to health and safety.
It is why unions such as the Electrical Trades Union has agreements that rule when temperatures are forecast to be above 35° Celsius, employees must be relocated out of direct sunlight or into an air-conditioned area.
RISK MANAGEMENT
CSS suppliers Beaver Brands and Paramount Safety—both market hydration products specifically formulated to rehydrate workers on site—argue it costs less to prevent a heat-related accident or illness than it does to recover from one.
Beaver Brands category manager Mariana Ryan, whose company distributes workplace electrolyte brand Sqwincher, says dehydration can affect overall work performance potentially impacting vision, tension, anxiety, fatigue and memory. It is also linked to short-term memory loss, mood swings and impaired motor performance.
Ryan says the human body is made up of around 60 per cent fluid. Dehydration is defined as a one per cent or greater loss of body mass because of fluid loss.
During normal activity, which includes breathing, perspiration, urination and defecation, the human body loses around 2.5 litres of fluid that needs to be replaced daily.
“Even in mild dehydration, loss of two per cent body mass or more, can cause a decrease in performance of up to 50 per cent,” she says.
Ryan says one of the most serious and life-threatening complications arising from dehydration is hypovolemic shock. “It happens when you lose more than 20 per cent of your blood or fluid supply, which prevents the heart from pumping enough blood to keep the body running. It can lead to organ failure and requires immediate emergency medical attention.”
Whether taken in powder, liquid, concentrate or freezer pop format, electrolyte enhanced products are often used on busy worksites as a quick way to increase fluid consumption while aiding hydration and preventing dehydration.
This is because electrolytes such as chloride, potassium, magnesium, calcium and sodium help transmit electrical signals between the cells.
If they’re unbalanced because of dehydration, these messages can become mixed up and lead to seizures, and occasionally, loss of consciousness.
“Your body runs on electricity, whether it’s the neurons firing in your brain or the pumping of your heart. Electrolytes are chemicals that conduct electricity when dissolved in water. When they interact with other electrolytes and with cells, they keep the body’s small electric currents flowing. Not only does this help your body’s natural processes run smoothly, but it’s also essential for your survival,” Ryan explains.
EMPLOYER RESPONSIBILITIES
SafeWork Australia says employers must do everything that is ‘reasonably practicable’ to eliminate the risks associated with working in heat.
This may include the cancellation of certain work tasks, the rescheduling of tasks to cooler parts of the day or waiting for hot conditions to pass.
Under the WHS Act, which can vary between states and territories, if an employer cannot eliminate the risk, they must make concerted efforts to minimise it. This can include everything from using automated equipment or processes such as a drone to inspect a fire ground, using plant or other equipment to reduce manual labour or establishing work-rest schedules.
Luke Michael, brand manager of Thorzt, a leading provider of hydration solutions, emphasises the importance of educating workers about the signs and symptoms of heat stress.
“Recognising the warning signs in oneself and colleagues is crucial,” Michael says. “Factors like age, fitness level, and medication use can help identify those at higher risk.”
To mitigate heat stress risks, many workplaces employ tools such as the Wet Bulb Globe Temperature and Thermal Work Limit indices to monitor heat conditions. However, Michael warns that these tools have limitations and should be used in conjunction with other preventive measures. A comprehensive heat stress management policy is essential, he says, covering specific responsibilities for key personnel to prevent, identify, manage and control heat stress.
