Dehydration remains a serious risk for Australian workers.

If workers are mildly dehydrated at the start of their shift, then it is difficult to fully rehydrate over the course of that shift. This can adversely affect worker productivity and safety. The implications of mild dehydration in the workplace are linked to reduced cognitive function and increased risk to workmates. When dehydrated, we’re not functioning at the top of our game, often resulting in poor concentration, reduced short-term memory and slowed psychomotor skills. Drinking water, our liquid gold, leads to better cognition and mental performance. It also helps combat tiredness and fatigue. Drinking water can help organisational productivity.

Hydration levels in cold climates also need to be managed. We know it is tougher to drink regularly when in cold weather. The “micro-climate” while wearing layers of gear that protects us from the elements means the sweat rate is not obvious, yet significant volumes of fluid can still be lost.

Reference points of dehydration:

• 1% dehydration – will lead to reduced physical work capacity and cognitive abilities
• 2% dehydration – starting to get thirsty. Heart rate increases and overall performance reduces. Thirst is not a good indicator of hydration levels
• 3% dehydration – impacts your cognitive ability. It is like trying to function with a blood alcohol level of 0.08
• 4% dehydration – further slows coordination and reaction times

These reference points can only be validated if individuals are weighed on a regular basis and their weight recorded.

Sweating helps the body get rid of body heat. However, sweating is not cooling. Evaporation of the sweat from the skin does the cooling. If evaporation is not happening, then the body’s core temperature could increase. Unfortunately, the body’s core temperature does not increase in a linear manner but exponential. This exacerbates the dangers of increasing core temperature. Small changes to the mechanics of regulating body temperature will impact performance and function.

Sweat rates for workers:

Working (10-hour shifts) in a temperature range of 15-20C, sweat rates can be around 4.0 litres per shift. This can increase to nearly 5.0 litres when working at 30-35C. A temperature of 35C is deemed to be within thermal work safety limits.

As workers acclimatise to the heat some wonderful physiology starts to happen. The body increases its ability to retain water more efficiently by retaining more salts. Non-acclimatised individuals working in hot, humid conditions will have evidence of salt marks on clothing. Fortunately, this level of salt will decrease as acclimatisation improves.

Mitigating dehydration risk is like any other safety hazard.

Science has proven that productivity and work function can suffer when we fail to adequately hydrate. Optimum’s data indicates that around 25% of employees report having discoloured urine during the working day. We also have evidence to suggest that the bigger the waist measurement of the individual the more likely this person will work with discoloured urine.

Employees with underlying health conditions or illness are also more susceptible to heat stress and complications from dehydration. Facilitating healthy hydrating habits and stressing the importance of hydration in the workplace is crucial to maintain a healthy and safe workplace environment. Organisational leaders need to educate employees and line managers about the best ways to hydrate, particularly targeting groups working in hot environments and those that carry greater risk, to themselves, their workmates and the organisation.