Keeping workers safe from dehydration

Workplace Safety Matters

Dehydration costs employers money

On the surface, dehydration and heat related illnesses make up a small fraction of worker compensation claims. In 2010-2011, they accounted for about $238,000 of a $57 billion bill. With figures like these, it’s not surprising that heat stress management isn’t exactly the cornerstone of every employer’s OHS agenda. But it should be.

You see, cases of dehydration and heat stress only become documented if the symptoms are so severe as to require medical attention, time off work and financial compensation. What these figures don’t reflect are the far more prevalent cases of ‘mild’ dehydration (classified as anywhere from 1-5% dehydration), and the increased incident rates/reduced productivity that happens as a result.

Even Mild Dehydration Impacts Productivity

    Just 1% dehydration has been found to decrease worker productivity by 12%. The more dehydrated the worker becomes, the further his or her physical work capacity degrades, with 3-4% dehydration bringing about a 25-50% decline in worker performance.

    Even Mild Dehydration Effects Worker Health & Safety

    At just 1% dehydration, workers begin experiencing decreased cognitive abilities, reduced concentration and alertness, and slower reaction times.

    1% dehydration represents about an 800ml fluid deficit for an 80kg adult male. With average Australian industrial workers sweating anywhere from 1L to 2.5L/hr, dehydration can set in very quickly if lost fluids are not actively replaced.

    Drugs & Alcohol Are Not The Only Form of Impairment

    3% dehydration can slow your reaction time to the same extent as 0.08 Blood Alcohol Content (BAC). At 0.08 BAC you are 5 times more likely to crash your car, which begs the question – how much more likely are you to have a workplace accident when dehydrated?

    Workers Show Up Unfit For Work

    Studies of Australian mine sites have found that 60% of workers report to work insufficiently hydrated for working in hot conditions,  with over half found to be at least 2% dehydrated. Once dehydrated, the situation usually deteriorates throughout the day with workers typically replacing only half of the fluid they lose through sweat.

    Educated Workers Do Not Become Dehydrated

    Studies have found that workers who are educated on the importance of hydration and engage in program drinking (as opposed to drinking ad lib) report for work hydrated and maintain this status for the duration of their shifts.

    6. Workers Cannot Keep Hydrated by Drinking Water Alone

    When we sweat we not only lose water but also essential salts and minerals known as electrolytes. Electrolytes play a number of key roles in the body, and one of these is water retention. If lost electrolytes are not replaced, a phenomena known as involuntary dehydration can occur, whereby the body struggles to rehydrate even when fluid intake exceeds sweat rate.


    Dehydration & Heat Stress Are Two Sides Of The Same Coin

    Our body’s core temperature is about 37ºC. When external temperatures are below our core temperature, we lose heat via radiation (the movement of heat energy from a warmer to a colder object). When external temperatures rise above our core temperature, radiation cannot work and the body relies solely on evaporation to expel excess heat. To do this it produces sweat which evaporates from the surface of the skin, cooling surface blood cells. The cooled blood then returns to the bodys’ core, lowering our core body temperature.


    Workplace Risk Rises With Temperatures

    A North American study examined the correlation between rising temperatures and accident rates. It found that the rate of workplace incidents rose dramatically in hotter summer months, with a rise in temperature from 20ºC to 24ºC corresponding with a 30% increase in workplace accidents.

    Similarly, a recent performance study by NASA examined the effect of ambient temperature on the error rates of telegraph key operators. The results were as follows:

    Temperature Mistakes in first hour Mistakes over 3 hours
    27ºC 5 19
    32ºC 9 27
    35ºC 60 138